اموزش vray [گرداوری]

دوستان سلام

ارائه و گرداوری کلیه آموزشی مرتبط با vray به صورت مستقیم انگلیسی از سایت های معروف در این تاپیک .

حالشو ببرین:11:

Creating a Realistic Looking Object Using V-Ray In 3D Studio Max

By [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] | 3D Studio Max | Intermediate This tutorial will teach you how to create a realistic looking object using V-Ray which is a very popular renderer that is widely used in the making of movies and videogames. V-Ray is not a built-in tool in 3D Studio Max and will have to be installed before attempting this tutorial. You can learn more about V-Ray from the official website of [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] - the makers of V-Ray. This tutorial is only involved with the process of creating a V-Ray render and will not involve any modeling. You may want to have a view at other [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] hosted at Oman3D if you would like to learn about other topics such as modeling.
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There are three different elements in our scene above, the teapot, the floor, and the surrounding environment. We will have to create and apply three different materials to each of these objects to create our final scene. The texture on the floor was created using an external image editor, and the same goes to the image reflected on the pot as well. We have uploaded the textures that we have used so that you can follow this tutorial easily. Please download the zip file at [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] and extract the two files in it before we start this tutorial.
We will start by setting up our scene; go to Create>Geometry>Plane to create a simple plane in the centre of our scene. Your plane should have the following specs: Width: 150, Length:150, Length Seg: 1, Width Seg: 1, Render Multipliers: 100.
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We are using the 'Teapot' object in our tutorial. You may use any object that you wish, but for the sake of the tutorial add a 'Teapot' by going to Create>Geometry>Teapot and set its parameters as illustrated in the image below:
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Our scene is now ready, before we start creating our materials, we need to setup the render engine to use V-Ray. Start off by going through Rendering>Render>Common>Assign Render>Production>Vray Render and set the initial parameters of the renderer under the "Renderer" tab as illustrated in the image below:
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The Adaptive Subdivision is one of the three antialasing algorithms that V-Ray uses. The Irradiance Map is a method of computing the illumination only at specific points in the scene. Please refer to the V-Ray documentation for more information.
Under the same tab, find the "Environment" rollout and activate the two available "Overrides" - Namely, the GI Environment and the Reflection Environment effects. You will have to assign a material for both which will work as environment map, click on the button that says "None" to access the "Material/Map Browser" where you would have to look for and select "VRay HDRI". After clicking on OK, you can simply drag the now "Map#1 (VRayHDRI)" to the button below it saying "None" to duplicate its content.
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Click to Enlarge
While keeping the VRay window still open, access the "Material Editor" by pressing "M" on your keyboard or going through Rendering>Material Editor. You will then have to drag the button you dragged earlier "Map#1 (VRayHDRI)" to the first slot in your Material Editor.
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Click to Enlarge
We will now use the map that you have downloaded at the start of this tutorial. Select the first slot in the Material Editor and then click on "Browse" under the Parameters rollout. Find the map that you have downloaded. Once selected, set the Map type to "Cubic environment".
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Floor Material

Select the second slot in the Material Editor and then click on the "Standard" button to open the Material/Map Browser. Select "VRayMtl" from that list and click on OK. Click then on the square button next to the Diffuse colour to open the Material/Map Browser once again, this time you have to select "Bitmap" to use the Bitmap.jpg that you have downloaded at the start of this tutorial.
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Click to Enlarge
Search for the "Coordinates" rollout in the materials properties and set the 'tilling' to X=1200 and Y=1200. You would also have to set the Mapping to "Planar from Object XYZ". Our material is now almost done. Apply it to the plane that we have on the stage by clicking on the 'Assign Material to Object' button: [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] .
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We are now going to make our floor more realistic by adding bump and reflection maps to it. Get back to the parent material by clicking this button: [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] . Scroll down and open the "Maps" rollout and drag a material from 'Diffuse' to the "Reflect" map. Select a copy on the pop up window and drag it again to 'Bump" map and select "Instance" on the pop up window. Go the Bitmap Settings of 'Diffuse', look for the "Output" rollout and set the Output Amount to 1.3.
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Click to Enlarge
The Teapot Material

We are going to create our final material now. Select an empty slot in the Material Editor. Hit the 'Standard' button and select "Raytrace" from the Material/Map list. Change the 'Diffuse' colour to dark red (or whatever colour you wish to use for your pot!) and set the reflection colour to gray. Set the specular level to zero. Finally, drag the material in the first slot (Our VRayHRD material) to the Environment map.
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Click to Enlarge
You can optionally change the reflection colour to white to get a more mirror like reflection on the teapot. You do not have to do this for our tutorial, but it is a nice element to experiment with on your own. You can now simply apply the material that we have created to our teapot using the "Assign Material to Object" button. Render the scene once you're ready and you should get something similar to the image displayed here:
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This concludes our tutorial, if you need any more help please visit the [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] .
- End of tutoria



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Using VRay Global Illumination GI (Realistic Lighting)

By Aziz | 3D Studio Max | Intermediate This short tutorial on how to use VRay's Global Illumination feature will show you one method for creating realistic looking lighting for a scene. VRay is a very powerful external render engine for Max made by [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] . VRay has many features including the ability to to physically accurate full global illumination, advanced material shaders and enhancements for speeding up rendering time. You can check the [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] website to learn more about the various VRay features.
This is an intermediate level tutorial and it will not explore any modelling techniques, you will have to create a simple scene with a few objects laying around to follow this tutorial.

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Assigning V-Ray As The Max renderer Engine

Start 3DS Max and assign V-Ray as the renderer engine. To do this access the Render Scene window by hitting F10, scroll down to the Assign Renderer rollout and expand it by clicking once on it, then click on the "..." button next to the Production field and select V-Ray from the list.

[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]
Creating and Setting Up the Lights

Access the Modify tab and go through light>VRay Light to start creating VRay lights. The number of VRay lights that you will need for a scene will depend on how big it is, for our project here I am going to use six VRay lights, I placed them on the inner upper part of the box, in other words, on the ceiling, the light always go there, right?

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Access the Parameters rollout to change the default settings of all the VRay light you added to the scene, I applied the changes illustrated in the image below.

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Setting up the Render Configuration

Once all the lights are fixed in the scene, open the the Render Scene window by hitting F10. Access the Render tab to turn off the Defaults Lights - this lets us deal with VRay Light for light calculations in render time only.
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Scroll down to the VRay-Indirect Illumination GI rollout, activate the GI feature by checking the On button, and then change the value of the Second Bounces to 0.9 and set the GI engine to Light cache, as illustrated in the image below.
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Scroll down and look for the V-Ray-Irradiance Map rollout and apply the settings illustrated below.
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Irradiance is a function defined for any point in the 3D space and it represents the light arriving at this point from all possible directions. In general, irradiance is different for every point and in every direction. You can learn more about Irradiance map from the [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] .
Look for the V-Ray-Light Cache rollout, and check Show calc. phase option as illustrated in the image below.
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Light Cache: is a technique used for approximating the global illumination in a scene in order to create a clean soft shadow. For more info please check [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] .
Move on to the VRay-rQMC Sampler rollout and increase the value for the Global subdivs multiplier to 2.2. Then go down to the VRay-Color Mapping rollout and apply the changes illustrated in the image below.
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Conclusion

Here is my end result which for the demand of my client has low intensity of lighting without texture.

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I hope that this tutorial will help you to start using the VRay render engine, make sure that you experiment with the different settings to discover new possibilities. Please feel free to email me at [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] for any suggestions or questions, you can also alternatively post at the [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] .
Links to other VRay tutorials:





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V-Ray Tutorial - Studio Lighting (3ds Max)
Free 3ds Max + V-Ray Tutorials by CG Artist, Géza Kádas
CGIndia Feature


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OVERVIEW
In this tutorial i will tell you the method of studio lighting.
For the rendering i used Vray 1.5rc3, the latest version of the program.
This famous chair called "Corbusier" was modeled in 3ds max 9.
With the knowledge of this tutorial you will be able to present your models
in a more ambitious way than before.. and especially helpful for guys into 3d architectural modeling...... ;)


The main parts of the tutorial are :

-Making the environment
-Placing the lights
-Setting up Vray for tests
-Shaders
-Setting up Vray for final rendering
-Postwork in Photoshop

MAKING THE ENVIRONMENT

The environment is pretty much simple.
Place a plane under the model and set 3 for the Length segsments and set 2 for the Width segments.Convert it to editable poly with right click on the plane and choosing "convert to:".
The next step is selecting the two edges behind the chair and pull them up while
pressing the shift button...
With this way create a shape around the model like in the third picture.

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We will use a Turbosmooth modofier on the plane, but to controll the way of smoothing
we have to chamfer a few edges before.
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Now we are able to use the turbosmooth with 2 Iterations.





V-Ray Tutorial - Studio Lighting (3ds Max) --- PAGE 2
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PLACING THE LIGHTS - This topic is the heart of the studio lighting.
We will use 3 vraylights with different strength, postion and color.
This three attribute will determine the mood and the individuality of your render.
So place a vraylight from left view, with the given settings.

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Now change to top view ,copy the light and mirror it to the X axle.
Place it to the right side of the plane and use the given settings.
The third light will be placed later, after the test renderings.

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Create a Target Camera from top view with 35mm lens, and set it up as you see.


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All right,choose vray as your primary renderer.
Make a vray material with a light grey diffuse color, R:170/G:170/B:170.
Put this material to the "override mtl" slot in the Global Switches tab.

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Now all the objects in the scene will have this material, so this function is
great to test lighting with a clay render.
Later we will turn this function off.
Hit F9 and lets see what we got here.

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So this is what we have without any settings.
No illumination,or any kind of sampling except the standard one.
Now we need to set up vray for test renderings.
It is time to move to the next topic.




V-Ray Tutorial - Studio Lighting (3ds Max) --- PAGE 3
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SETTING UP VRAY FOR TESTS

To test the illumination in the scene we need to set up vray with low values.
These are only tests ,so we only want a quick feedback from the lighting.
First of all change the image aspect ratio to 1.8 in the Common tab.
Go to camera view and turn on the "Safe Frame" option.
Safe Frame will help you to place youre camera to the right position and it
is also helps to notice unwanted parts in the view.



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Now here comes the capital part of the Renderer tab settings.

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Here is a short explanation of the settings above:
Default lights: turn it off ,we do not want any light, except the vray ones.
Adaptive QMC: A faster image sampling method than Adaptive subdivision.
Mitchell-Netravali: With this antialiasing filter edges will be sharp but not crisp.
Irradiance map + Light cache: the mostly used GI combination.
HSph subdiv: (GI samples) lower it to speed up the rendering process.
Show calc phase: The rendering process will be visualized, so if are not happy with
the effect you don't have to wait until the effective rendering.
Subdivision: The subdiv. of lightcache controls the number of traced paths...
The actual number of the traced paths is the square of the adjusted number.
So with 500subdiv. 250.000 paths will be traced.
Exponential: With this type of colormapping ,colors will be saturated so you can
avoid burnouts on the surfaces.
Dark multiplier: This controls the "Sternth" or the multiplier of dark colors.
Render region division: set it to 32x32 ,smaller bucket size less ram will needed.
with samller bucket size a faster feedback can be achieved.

All right, lets see the render with the mentioned settings.

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It is much better than the first one.
The scene is much more brighter, light is smoother and there are no burnouts.
Because of the low quality settings there are GI artifacts ,noise and blurry lines.
However ,these settings provide us a very efficent way of testing.
Lets play with the colors to break the dull feeling of the render.
Change the color of the vray light on the right to R:255/G:180/B:80.
This warm orange color will take care of the monotonic lighting.

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At this point if you are satisfied with the result you can go to the next step.
Creating and understanding shaders is the following topic.




V-Ray Tutorial - Studio Lighting (3ds Max) --- PAGE 4
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SHADERS

In this scene i used four or five shaders.
Plasctic,Chrome,Leather,White fabric, and the white background of course.
Turn off the "override mtl" function in the Global Switches tab.
Lets take a quick look at the settings.



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Diffuse: This controls the color of the material.
Reflect: Pure white means 100%reflections ,black means 0% reflections.
Refl. Glossiness: Controls the blurryness of reflection 1 means perfect
mirror-like reflections, lower values produce blurry reflections.
Subdivision: This controls the quality of glossy reflections, higher values
increase rendertime lower values produce noisy effect.
For testing /5-8/ final rendering /15-35 or higher if necesarry/.
Freshnel reflections: If you check it that means the strength of the reflection will
depend on the viewing angle of the surface.
In nature water and glass is reflecting in this manner.
The strength of the reflection depends on the Freshnel IOR too.

All right lets see the shaders in action...:)

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I am pretty happy with the reflections on the leather material.
I only need a little more light from above the chair, so lets put that third
vraylight to its place.


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It is important to uncheck the "Affect Specular" slot, we don't want any
specular reflection from that light ,only diffuse light.

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As we can see the bounced light reaches to the bottom of the chair too.
Now the lighting and the shaders are finished so lets move on to the next topic.
I will discuss the settings of the final rendering.




V-Ray Tutorial - Studio Lighting (3ds Max) -- PAGE 5
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SETTING UP VRAY FOR FINAL RENDERING

At this ponit of the workflow it is very important to find the balance between speed and quality.
I will talk about the settings globaly, because some problems can't be solved
with only changing the value of an option.
So lets see the Renderer tab in this light :)



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-Change the resoultion to 900x500
-Set the Adaptive rQMC image samplers min dubdiv to 2.
Now thinner lines can be rendered correctly.
-Change the preset of the Irradiance map to Medium from Low.
Set 50 to the HSph subdiv to achive higher quality GI.
-Use value 1200 for the Light cache subdiv.
Change the Sample size to 0,006 ,now small details will be more visible.
Use value 1000 to the Pre-filter option to reduce noise.
We have a lot of glossi rays so check the "Use light cache for glossi rays"
option./it will speed up rendering/
For the Filter use the "None" possibility.
-At the rQMC sampler use value 0,005 for noise treshold.
Set the Global subdivs multiplier to 4 ,it will increase samling quality
everywhere in the scene.
-You can find the Light properties in System>Lights settings.
Changing the diffuse subdivision of the lights wil effect the number of
the traced photons.
-Change all the vraylights subdivison to 15 or 20 to avoid noisy parts.
-Change all the materials subdivs to 20 in the Reflection section.
With these settings the rendertime will increase a lot according to test render settings.
Now hit F9 and wait until the calculation finishes.

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This is the final rendering, no noise ,artifacts or any nerve-racking rendering trouble.
A picture would not be complete without the postwork so lets move on.


V-Ray Tutorial - Studio Lighting (3ds Max) -- PAGE 6
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POSTWORK (in Photoshop)

Launch photoshop, and load in the image.
Because of the saturated colors of the exponential colormapping type.
We need to add more character to the colors and play with the levels
to achieve better contrast.

Go to Image>Adjustments>Color balance

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Than Image>Adjustments>Levels

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And here comes the finished picture.

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Congratulations ! you finished the tutorial...
I hope you liked it. ;)



Author: Géza Kádas
About Author: Originally I started my study with webdesing. After a few years I become acquainted with 3dimensional programs. I completed a 3ds max master course, after that I spent a lot of time to get familiarity with the program. Architectual visualisations are my favourite topics in the 3d industry, both exterior and interior scenes. Currently I study as an interior decorator.I am working as an instructor at IMMI (International Multimedia Institute).
Email: [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]
Homepage: [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]


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* 3DS Max Video Tutorial, how to 3D Model a Car Rim - [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]
* Two 3ds Max Video Tutorials For Beginners (highway |basket ball) - [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]
* 3D Modeling and rendering Quad Bike in 3ds max - [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]
* 3D Modeling and rendering MayBach 57 in 3ds max - [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]
* Learn 3D Modeling a Digital Radio in 3D Studio Max - [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]




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آموزش دکراسیون داخلی و نور پردازی Vray
تذکر:ctrl+a بزنید نوشته معلوم شه:46:

[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] CREATED IN:

3D Max 9 and Vray for rendering, for post work I always use Photoshop.
CONCEPT:

This was a client work, and we ask me to create a simple and modern Bathroom with similar lines as the exterior house (FIG. 1), very simple and with a lot of concrete and Wood.
So I start for making a simple sketch in paper with the idea and after the approval from the client I get my hands to work! (FIG. 2).

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MODELING

Due the fact this is a client job and the time is limited I use some premade models for filing the scene and make this more eye appealing!
BATHROOM MODELING

The Bathroom modeling actually is very simple, I started with a spline and from the top view I started modeling the bathroom walls, then with the extrude tool I give that walls volume. (FIG. 3). To create the windows and doors in the walls I convert the model to editable poly and then use the cut tool for creating them (FIG. 4).

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The ceiling and the ground floor are just planes and simple boxes.
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] After making the base model I start to add detail to the bathroom, first was the wood panels in the wall, I fill all walls with panels in wood, for making this I use the Chamfer Box (In the Geometry > Extended Primitives > Chamfer Box) with the Following values (L;W;H;F) 90cm; 90cm; 3cm; 0.50 cm. (FIG. 5)
For the wood/metal plate around the bathroom I use a spline and then use the extrude modifier again to give volume. (FIG. 6)

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JACUZZI MODELING

Like all previous models this is very simple to make, started with a plane and then use the extrude tool to make the walls and bottom Jacuzzi, chamfer the corners, etc… The only problem I have was the water, I want to give the water that ripple running felling, for that I create a plane with many subdivisions and place under the water fall and with the Paint deformation tool I create some circles around to give the ripple sensation. (FIG. 7)
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THE CARPETS

As always, I started with a spline from the top view drawing the contour, then I add a Vray Fur modifier with the following parameters (FIG. 8)

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All models I made in the same way, using splines ore polimodeling.
TEXTURING

All textures and UV maps as the whole model so far are very simple, for that I use only Vray materials and I didn’t unwrap anything, so I’m just going to focus in some of them. (FIG. 9)

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Every map I applied have only planar; box and cylindrical Uv’s.

1 - Wood Panels FIG.10
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 2 - Concrete Ground/ Jacuzzi FIG. 11
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 3 - Water FIG. 12
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4 - Metal Bar on the wall FIG. 13
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] Two other materials I don’t have in the image but is useful to mention is the Background Image and the Glass Block.

BACKGROUND MATERIAL

Once I don’t have a HDRI for this image I use a VrayLightMtl with a .JPG image applied, with Intensity of 2 in the color slot, this will give me a soft light and reflections in the interior. (FIG. 15)
GLASS BLOCK

This map comes along with max, you can find him in the ArchMat Folder in 3dmax root; the only thing I made was creating a Gap mask, so I can control the Gap Color between Blocks (FIG. 16)
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5 - Acid Glass FIG. 14 [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] LIGHTS

For Lightning This Scene I Use a Directional Standard Light That I’m gone Called ‘’SUN’’, Two Big Vray Lights Filling the Exterior Windows And Doors and 6 Omni Light in The Fake Ceiling to create Indirect Light in the Walls. You can see the lights in the Fig. 17 – TOP VIEW – And FIG. 18 (FRONT VIEW)

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Little explanation about the Lights I Use:
THE SUN

I Use a Standard Directional Light for Simulating a Very high Sun Position with Sharp Shadows.
This light have a Yellow Color (RGB: 255; 255; 200) in the slot with a 0.85 multiplier and Vray Shadows. (Remember I use these values for this image particularly, not every model/image has the same parameters, and everything influences the light; model dimensions, sun high, day time etc…)
Also in the Directional Parameters don’t forget to mark the Overshot Slot and Chose a Falloff big enough to cover the model.
VRAY LIGHTS IN WINDOWS:

I use this kind of light in the windows because even I use GI in Render this is not enough for lightning the interior, So for this I create big Vray light planes filing all windows in the Scene, with this I will have more light in the interior with soft shadows and that’s what I need to simulate the bouncing sky/sun light in the model.
In this case particularly the Vray lights have a Blue Color (RGB 231; 238; 241) and with 3.0 Intensity.
Also in the Vray light Options Check the Invisible Option (with this checked, you will not see the light plane and the sun can pass thru the Vray light plane)
Normally when I use Vray lights in the scene always use a very high subdivision sampling, in these case 65 subdivisions, with this I remove almost all noise this light produce in the scene.
This is a little boring sometime because more subdivisions you have, more time you will render, so if you don’t have a faster computer I don’t recommend to use a very high subdivision sample.
OMNI LIGHTS IN FAKE CEILING:

Instead of using Vray lights in the ceiling for simulating a decay light in the wall I replace them with Omni lights, with this solution I render faster, (Note: Only use Vray light if you don’t have any more light options, these lights are very good but take longer to render), after this another problem… How can I block the light in some places to give impression that I have a Fluorescent light? Simple solution, in the ceiling above the Acid glass i add some boxes separated 1 meter each, with these simple solution I give the impression that i have a florescent light there. (FIG. 17 and FIG. 18 – Detail in the ceiling)
In this case particular I have 6 instanced Omni light with a pure white color with 1.30 intensity multiplier. All lights have Vray shadow
RENDERING

As I said previously, for rendering I Use Vray, for me this Render engine is very useful, either in interior or exterior Architectural renderings.
I do always the same things before rendering final Images…
- Ensure I have a good subdivision in the Materials parameters (Both in Reflection and Refraction Slots).
-If I have a value in the Refl. Glossiness (Reflection) or in the Glossiness (Refraction) less than 1.0 I must increase the subdivisions to remove the noise from the material.
- 25-50 Subdivisions is good for almost every material
- 8-12 Subdivisions is good for Metals like Chrome; gold; Stainless steel…, Etc…
Note: Remember, if you increase the subdivision the render time will increase too. So try to balance between materials and render time… if a material is less visible you don’t need to increase the subdivisions!!!
- Test renders to View models/materials in place end light.
Light/render Tests in Vray always take longer because this is a very slow render engine, the fastest method I have is in the following parameters (FIG. 19)

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This will create a very ugly and noisy render but is fast, you can see the models/materials in place and if you need more light, or not.
- Ensure nothing is blocking the lights; in these case I have the Background plane, the plane is blocking the sun light because is very close to the window. (FIG. 20)
For that, I go to the Object Properties and uncheck Both Receive and Cast shadows.

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Finally, the Final render…
My Interiors almost the times have the same final render settings (FIG. 21)

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After the render I always make some color correction with Photoshop, to give that Glow look in some pictures in Photoshop I duplicate the layer and then go to Filters > Blur > Gaussian Blur (2.0 Pixels Radius) Blend with the Original layer using Lighter Color and change the Fill Value until I get a good result. (FIG. 22)

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I enjoyed making this article and I must thank you all for reading it.
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If you have any questions, comments, criticism or anything else that you want to share with me, please send me an email and I try to get back to you soon as possible.
s.





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آموزش ساخت متریال سربی Vray-Chrome


If you want very realistic render, you need V-ray. In this tutorial you wiil learn how to create chrome material. For this tutorial you need V-ray plugin. On picture below I used my chrome material.
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Open Material Editor by pressing M on your keyboard.
Click on Get Material button, and chouse Vray material from Materail/Map Browser.
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Rename material to “Chrome”
Click on Diffuse color, and set to black.
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For the Reflec color use this settings:
Red: 242
Green: 242
Blue: 242
Turn on Fresnel reflections and Fresnel IOR. Change Fresnel IOR to 16. Set Max depth to 10. See picture below.
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In the Refraction menu change Refract color to black and change Max depth to 10. See picture below.
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Make sure that BRDF menu is set to Blinn
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The End.


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آموزش رندرینگ HDRI in Vray



HDR Images in Vray

Before you start

This tutorial assumes you have a basic Vray and 3DS Max knowledge, and an official Vray copy. I used version 1.47.03 while making the tutorial.

You have to be able to create Vraymaterials, load maps in the material editor, open the render settings dialog etc... This tutorial also uses of Vray GI, I will not explain these settings in this tutorial. Check out the other tutorials on my site for that. step1: Basic settings

First, open 3D Studio Max... Make sure you set Vray as the production renderer. For test rendering, lower the output size to 480*360px. This is the easiest way to speed up rendering while testing!

Go to the global switches rollout and turn off 'default lights'. We don't want the default lights to interfere with our lighting, since this will be based only on the hdri map! [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] step2: Anti Aliasing settings

I always render with the Adaptive QMC image sampler (see screenshot) because this allows for great control over every aspect in the scene with only a few mouse clicks.

Also turn off the anti aliasing filter, this speeds up things too. Only use one of these filters if you can't get good enough AA on fine textures or very small details. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] step3: Create the testscene

Make a small testscene which you want to render. Start with something simple! I made a cylinder with a max teapot on it :-) [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] step4: First render test

Hit render and enjoy a black picture! If it's not black you forgot to turn off 'default lights' in step1.

The reason for this is quite obvious, there is no light in the scene, so it's completely dark. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] step5: Let there be light!

Go to the Environment rollout and turn on both GI and environment overrides. Leave them at default colors. Hit render again, you'll see it is still black! [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] step6: Let there be GI light!

When using the Vray skylight option, you need to enable GI to make it visible. The sklight is treated as first bounce GI light, it's not a direct light as for example a max spotlight or Vray area light.

So open the Indirect Illumination rollout and enable GI ('On' checkbox). [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] step7: Render again

If you hit render now, Vray will start calculating the GI coming from the skylight, and after that the actual rendering will start. This can take a while on slow machines!

Shadows are very diffuse because of the skylight. Light is coming from all directions with equal strength, so there are no directional shadows. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] step8: Speed up rendering

The default irradiance map settings are too slow for test rendering, so we will speed things up by making some adjustments.

First I lowered the secondary bounces to 0,8 (GI rollout). Then choose 'custom' in the preset list to have full control over the settings. Fill in all the other settings like I did (click image on the right). The most important are Hsph subdivs and the min/max rate. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] step9: Helpfull settings

Also change the render region division to 32*32 in the system rollout (good for small resolution images only!).
Check the frame stamp box and delete everything except the render time part.
Render again if you want to, notice how fast it renders now! [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] step10: Create Vray materials

It's always best to use Vray materials if you can, they will render faster in many cases, and the chance of incompatibility is reduced.

Make a very light grey VrayMaterial for the groundplane, and a fresnell reflective one for the teapot. See my settings in the image on the right for the reflective material. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] step11: Render

After you created and assigned the new materials, hit render to see the result. Notice that the grey groundplane looks blueish, this is because of the light blue color of the skylight. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] step12: Play with environment colors

Make the skylight light yellow, and the reflection white with a 2,5 multiplier. Render again and notice the colour change and the stronger reflections in the teapot. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] step13: Load HDRI map

In the material editor, click the blue get material button and choose VRayHDRI from the list. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] step14: HDRI settings

Click the browse button and locate a hdri you downloaded from my website. All these HDRI maps are in 'mirrored ball' format. So check the mirrored ball option in the HDRI parameters.

Many free hdri maps are unwrapped (they look like an unwrapped globe), you need to set the type to spherical environment for these map types. Some are 'angular maps' (=light probes, like the old hdri's on devbecs website), so check angular map if you're using one of those. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] step15: Assign HDRI map

You can simply drag and drop this hdri map onto the 2 environment slots in the Vray environment rollout. Make sure you choose instance method!

What you did now is telling Vray to use the map for skylight and reflections instead of the color swatches. The multipliers have no effect anymore now! [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] step16: Render

Hit render! Skylight is now calculated according to the hdri map, also reflections are coming from the HDRI environment.

Notice the longer rendertimes when using hdri for lighting.

The lighting is a bit too strong. In the Vrayhdri parameters, lower the multiplier to 0,9 and render again. You'll notice there will be no blown out area anymore.

Play with the horizontal rotation to get the reflections and lighting to appear the way you want. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] step17: Final settings

- Set output size to 640*480.
- Change Irradiance map settings according to image on the right.
- Change the QMC Samplers noise threshold to 0.001
- Change the region render division back to 64*64px

Hit render and wait! These are high quality settings that are always good, but usually you can get away with lower ones to speed things up. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] step18: Final Rendering

Click the image to see the final rendering at 640*480 resolution. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] Notes:

If you want the hdri to show up in the background too, simply drag the map onto the 3ds max environment slot.

مرسی مانی جون

Before you start

This tutorial assumes you already completed the previous ones in the tutorial list.

It will provide a general workflow for a standard studio lighting setup: create the environment, place lights, adjust render settings.

The Vray version I used for this tutorial is 1.47.03.
1. Build a testscene

Start up max and set Vray as the renderer.

Go to 'customize - units setup' and set both the display unit scale and system unit scale to metric: millimeters.

Create 3 geospheres with radius 35mm and position them like I did. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]
2. The groundplane

We will try to build an infinite background in a simple way. Usually photographers use a big white or black cloth behind their scene, curved at the bottom, so that you will not see a sharp edge between back wall and floor.

There are of course lots of ways to do this. I will start from a cylinder, bend it locally and round it off with a meshsmooth modifier. This way, your groundplane is very smooth and round in all directions, making sure you will not have disturbing reflections from it (like you would when using a box for example as groundplane).

Click the image on the right to see all settings of the cylinder, bend and meshsmooth modifier. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]

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3. Create a camera

Now create a camera and position it like in the image on the right. Give it a 50mm lens. Set the perspective viewport to use this camera, enable 'show safe frame' so you can clearly see what part of the scene will be rendered. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]
4. Create materials

We need three materials: 1 almost white, 1 chrome and 1 red reflective.

Click on the image to see what settings I used for the chrome and red material. (this should look familiar if you completed the [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] )

Assign the materials to the spheres. The groundplane also uses the almost white material. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]
5. Test render settings

Open the render settings dialog and do the following:
- set Vray as the renderer if you haven't done so
- output size to 480*360px
- global switches: turn off default lights
- image sampler to adaptive QMC
- antialising filter "mitchell-netravali"
- indirect illumination ON
- Secondary bounces multiplier to 0.8
- Irradiance map settings:
- "low" preset
- hsph subdivs = 20
- environment:
- skylight pure white color, 1.0 multiplier
- reflection/refraction pure black, 1.0 multiplier
- system:
- render region division 50*50 px
- frame stamp: delete all except rendertime part.

Render the scene, it should look similar to my image. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]
6. Reflection planes / lights

Instead of the skylight, we will use big rectangular Vraylights to light the scene. They will also be usefull for creating nice reflections. (like we did in [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] )

Create two Vraylights and position them more or less like I did.

The left light is 400*350 mm with a 3.5 multiplier and the one on the right 360*500mm with 5.5 multiplier.

Then go to the Vray environment rollout and change the skylight multiplier to 0.1. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]
7. Render what we have for now

If you set all lights and sky multipliers like I did, lighting should be more or less correct. I made the right light brighter on purpose, that way you create shadows falling in one direction. If you would set them at equal strengths, the image will be uninteresting as lighting will be a bit flat, coming in eqaul strength from all directions. The bigger the difference between the two lights, the more dramatic lighting will be.

The first pic shows left=3.5 and right=5.5

The second one has left=2 and right=7

We will continue with the 2/7 settings. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]

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Before you start

If you discovered this Vray tutorial page through a direct link or search engine, please note that you're on page 2 of the tutorial! Please complete page 1 first if you haven't done so. 8. Noise!

You're probably wondering why the images are so noisy and take pretty long to render. This is because Vray area lights produce raytraced area shadows, and these are very processor intensive. The noise is coming from the low subdiv value in the lights properties.

Because we are using adaptive qmc AA, it is necessary to use high subdivs values for the area lights to get rid of the noise. Try 30 subdivs for both lights and render again. You can see the result in image 1 (click to enlarge)

Now go to the anti aliasing settings and change to adaptive subdivision AA with min/max=0/2. With this anti aliasing sampler, you can use lower subdivs than with adaptive QMC to have a similar noise quality. So change the lights subdivs both to 10 and render again. This is image 2 (click to enlarge)

[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]

[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 9. subdivision vs QMC

At first sight, you might think the adaptive subdivision image is better (less noisy). But if you look closely, the noise is just different, not 'better'. In the shadow area you get a 'blotchy' kind of noise, compared to the QMC example which is sharp constant noise.

The top image is the adaptive subdivision AA, the bottom one is the adaptive QMC AA.
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]

[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 10. Reduce the noise

We will now try to reduce the noise for both image samplers to see which one is the fastest for high quality images.

Set image sampler to adaptive subdivision AA, min/max=0/2
Adjust subdivs for both lights to 30 and render.
The image is noise free. If you zoom in a lot, you can see a tiny bit of the blotchiness.

Now change to adaptive QMC AA, min/max=1/4
Adjust lights subdivs to 36.
In the QMC sampler rollout, change the noise threshold to 0.002. The adpative QMC AA is very sensitive to the QMC sampler settings. The noise threshold is the most important one. (QMC sampler controls the quality of all 'quasi monte carlo' related calculations. In short, all subdivs settings are qmc related, except for lightcache subdivs)
If you zoom in here, you can also see a bit of noise, but sharper and smoother than the blotchiness of adapt subdiv AA.

But in this case, adaptive subdiv AA wins from adapt QMC AA. When you will add more complex materials like glossy ones, and more area lights, fine textures, displacement maps etc, rendertimes for adaptive QMC will not rise as fast as rendertimes with adaptive subdiv AA. Usually when you have lots of glossy effects (also DOF, motion blur,...) it is better to use adaptive QMC AA. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]

[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 11. Store with irradiance map option

Like I said, the reason for the noise are the raytraced area shadows. Especially for test rendering, we can easily disable them.

The light coming from a Vraylight (or also from standard Max lights) is called 'direct' light. This means it is not GI light (first or secondary bounce). Once this direct light hits a surface, it bounces back a bit (depending on how dark and reflective that surface is). That bounce is called the 'first' bounce, and it is calculated by the irradiance map (because we have set first bounce GI engine to irradiance map).

But the Vraylight has an option 'store with irradiance map'. This option actually means 'treat direct light as first bounce GI light'. Instead of casting direct light, the Vray light will now cast first bounce GI light and thus it will be calculated by the irradiance map. This also means that when it hits a surface, and bounces back, it will become secondary GI light, and it will be calculated by the secondary GI engine, QMC GI in this case.

So by setting the Vraylight to 'store with IR map', the result will be that there is no direct light anymore, only GI light. This means that all shadows will also be created by the GI light. The consequence of this is, that shadow quality doesn't depend on the Vraylight subdivs anymore, but the it is controlled by the GI settings, namely the irradiance map (and QMC GI for secondary bounces). This is important, the Vraylight subdivs do absolutely nothing if 'store with IR map' is checked!

(note that this option only works if IR map is set as first bounce GI engine. If you have for example QMC GI for first and second bounce, and lights with the 'store with IR map' turned on, these lights will not cast any light!)

To illustrate the store with IR map option, I rendered two images with the 'show GI only' option (global switches rollout). This option renders the image only with the GI light, so without any direct light that may be present in the scene.
The first one is with normal Vraylight (without 'store with IR map' option).
The second one with the 'store with IR map' option turned on.

You clearly see that in the first example, with the direct light extracted, there is not that much GI light to be calculated. And in the seond example, all light is GI light.

This step is very very important, you should really understand the difference between 'store with IR map' turned off or on, and the difference between direct/first bounce and secondary bounces.
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]

[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 12. Store with irradiance map option (2)

The disadvantage of this option is that there will be more first bounce GI light, but worse, also more secondary bounced GI light (calculating detailed GI light, especially second bounce, is very processor intensive). This means you have to rely on IR map and QMC GI calculations for the creation of nice shadows. In product renders this is not such a big problem, because there will not be much secondary bounces anyway. Light that hits the top of the spheres for example (=first bounce), will bounce back (second bounce) right into the sky. So this second bounce will have no effect on the rendering. Only a bit will bounce in between floor and objects, or from one object to the other. But the secondary bounces will not have such a big influence on lighting and shadow creation.

This will become more of a problem in interior scene lighting. There, the second bounce will not go to the sky, but it will probably hit a ceiling or wall, bouncing again and again... So in these scenes, the secondary bounces do have a great impact on final lighting look and shadows. So in this case, it would be a good idea to reduce the amount of GI light, by replacing the first bounce by direct light ('store with IR map' turned off). Think about it, instead of relying on first bounce GI light to start with, you now start with direct light which will illuminate a lot of the scene already (quality is perfect, it is direct light), then there is first bounce (ir map) and then second bounce. I will show this in the interior lighting tutorial.

To summarize, for product renders you can greatly benefit from the store with IR map option, as there are not much secondary light bounces. You will need to improve the IR map settings, resulting in longer GI calculation, but the actual rendering of the image will be a lot faster, as there are no difficult area shadows to render anymore. The total rendertime (GI calculation + raytracing the image) will be a lot lower than when you use true raytraced area shadows (here GI calculation will go faster, but actual raytracing will take a lot longer, so combined total result is much longer).

See top image with following settings:
- adaptive QMC AA 1/4
- noise threshold=0.002 in QMC sampler rollout
- IR map: see settings below top image
As you can see, rendertimes are cut in half, and compared to the raytraced area shadows examples, there is absolutely no noise at all! But shadows are a bit less precise.

Go to the IR map settings and change the min/max to -4/-3 and the hsph subdivs to 20. In the QMC sampler rollout set noise threshold to 0.005 again. These are very fast testrender values. Render the image again. Notice how less detailed the shadows are now (bottom image, spheres look like they float a bit). But hey, 11.3 seconds is not bad for a fully antialiased image :-)
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]

[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]

[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 13. The end

This concludes the studio setup tutorial.

By now, you should better understand the difference between adaptive subdivision AA and adaptive QMC AA, the effect of the 'store with IR map' option, and how to create a simple efficient studio lighting setup.

Save this scene so you can reuse it in some of the other tutorials still to come.



---------- Post added at 08:19 PM ---------- Previous post was at 08:15 PM ----------

Before you start

This tutorial assumes you already completed the other Vray tutorials before this one in the list. Also make sure you have basic 3DS Max skills, since Vray is a 3D Studio Max plugin, it relies on Max's functions a lot too.

You will learn the best way to model a glass with liquid inside, so that Vray renders it correctly. If you're having difficulty to understand some of the concepts used here, make sure you already completed the [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] . 1. Continue with the end result of the studio lighting tutorial

Delete or hide the 3 spheres, we don't need them anymore.

Set the render properties like this:

- output size to 400*480px
- global switches: turn off default lights
- image sampler to adaptive QMC
- antialising filter "mitchell-netravali"
- indirect illumination ON
- Secondary bounces: QMC GI and multiplier to 0.8
- refractive GI caustics ON
- Irradiance map settings:
- custom min/max=-4/-3
- hsph subdivs = 20 = interp samples
- clr=nrm=0.4
- dist=0.1
- environment:
- skylight pure white color, 0.1 multiplier
- reflection/refraction pure black, 1.0 multiplier
- QMC sampler: noise threshold = 0.005
- system:
- render region division 50*50 px
- frame stamp: delete all except rendertime part.

The Vray lights should have the 'store with IR map' option turned ON to start with. The left light has a value of 3, the right one is set to 5. Position them like in my screenshot.

Also adjust the camera postion like I did, set the lens length to 85mm.

Your scene should have both system and display units set to metric mm. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 2. Import my glass model

Glass is a material that everyone tries to render while learning or testing a new renderer. Vray is capable of rendering very realistic glass in a very short amount of time.

I already explained a lot about creating glass in the [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] . A lot of it will be repeated here, but this time we will render a real object instead of some weird blob like thing.

[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] (it's zipped!). Use the import function to bring it into the scene (turn off 'convert units' in the import options). The glass should be sized like in my screenshot. If not, simply resize it :-) (probably your units are set wrong or convert units was still on if the glass imports too big/small) [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 3. Move it up a little bit

Any renderer will always have problems with overlapping faces. Especially with transparent materials this can cause visible problems. The glass bottom faces lie exactly on the faces of the groundplane, they are in the exact same location. Although it will not be very visible here, it's a good rule to remember, avoid coincident faces! Moving the glass up by 0.2 mm is already more than enough.
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 4. Create the basic glass material

Create a new Vray material. We will first make clear high reflective glass. To do that, first set the diffuse color to pure black. Then set refraction color to pure white. Pure white means 100% refractive, resulting in the diffuse component having no effect at all anymore.

Make reflection color almost pure white and check fresnel reflections.

This is the base of our glass material. It is 100% clear, very reflective glass.

Assign to the glass object and render. It should look like my example. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]

[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 5. Reflect on backside

Notice the dark border on the inside glass surface? To get rid of this, we will turn on the 'reflect on backside' option in the options rollout of the glass material.

Render again to see the difference.

This option creates internal reflections, an effect that happens in real life too. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]

[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 6. Reflection/refraction depth

These options control the number of times a ray can reflect/refract before it is removed from further calculations. Lower numbers will cause faster rendertimes, but go too low and parts or the whole object will turn black.

Increase them both to 10 and render again. The difference is huge on the foot of the glass and in the middle part (because in these parts, internal reflections will happen a lot, exceeding the max depth quickly).

Values of 10 are ok, don't go too high because rendertimes will increase a lot! [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 7. Adjust the studio setup

Our studio setup is a bit 'too much' for this scene. We will adjust it by turning off the left light. To compensate for the light decrease, turn the environment skylight multiplier to 0.4.

Render the scene, it should look more or less like my example: [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 8. Filling a glass with water

To fill a glass with water, you should model the water. This isn't as easy as it sounds.
First of all, the surface of the water will bend up where it touches the glass because of adhesion forces. We call this curved top surface the meniscus. This effect has to be modeled or your water will not look very realistic.

Then there's the problem of coincident faces. If you model the liquid exactly as large as the inner surface of the glass, the rendering will look weird because of these coincident faces(right glass). The best way is to model the water a bit larger than the inner glass surface (middle glass). If you model it slightly smaller, it's not realistic either (left glass).

Click on the image to see examples of all three. I modeled the glass in rhino, it's a revolved curve. I show you these curves also to see how the glass vs water is modeled. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 9. Import the water

[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] and import it in max (turn off 'convert units'). The water should be positioned perfectly into the glass.

Create a new Vraymaterial, name it water and give it a pure white diffuse color.

Render the scene. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 10. Water material

Go to your water material and change the settings according to the image on the right. In fact, these are the same settings as the clear glass, only the IOR is different.

Also go to the options rollout and turn on reflect on backside like we did for the glass material. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 11. Render again

Now we have a nice wineglass filled with water :-)

As you can see, it's pretty easy to get a decent result for glass/water in Vray. Already our first render looked pretty good. But to fine tune it, you need to know some tricks. Questions regarding glass pop up a lot in the Vray forum, so I hope this tutorial will clear things up a bit :-) [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] Before you start

If you discovered this Vray tutorial page through a direct link or search engine, please note that you're on page 2 of the tutorial! Please complete page 1 first if you haven't done so. 12. Red wine

Copy the water material and name it 'red wine'. Change the fog colour to a saturated red, and turn down the multiplier to 0.05. This will tint refractions red. Apply the wine material to the water. Render to see the effect.

Experiment with different colors and multipliers to create other liquids too.

Of course you can do the same thing with the glass material, to create a colored glass. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]

[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 13. Expand the scene

To give the scene a more interesting look, we will copy the glass and put it on the floor like as if it was tipped over.

So select the glass model and copy it, rotate it and position it like I did.

Change the output render size to 430*480px. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 14. Roll the camera

With the rotate tool, roll the camera -8 degrees. Also move it to create a better composition. Render the scene, it should look like this. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 15. Smaller Vraylight

The shadows are very dim because our area light is so big. We will adjust the Vraylight, make it smaller and reposition it. You can see in the screenshot how I placed it. It's not only smaller but also placed further away.

U-size= 250mm and V-size=300
Light multiplier is set to 22. It's much higher because the area of the light is smaller.

Also change the sky multiplier (Vray environment settings) to 0.15 instead of 0.4. This way, the environment lighting will not brighten up the shadow regions as much as before. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 16. Nice caustics

This smaller light will also result in more noticable caustics.

Remember my rambling about GI caustics on [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] ? Well, here we will use them again.

First render the scene with the new light settings. It should look like my example. Notice the shadows that are much more visible now. The smaller the lightsource, the sharper the shadows.

[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 17. No GI caustics

In the GI settings, turn of refractive GI caustics. You will clearly see that shadows get darker. No light is able to pass trough the transparent materials.

This is just a reminder to show you the effect of GI caustics.

Turn the refractive GI caustics back on.

I usually don't use reflective GI caustics, because they do more bad than good in most cases. Refractive ones are way more important as you can see from this example. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 18. Sharper caustics

Because the shadow and caustics quality is controlled completely by the IR map settings, we will fine tune them.

Note that shadows are created by the IR map because we have 'store with IR map' in the Vraylight turned on. So our Vraylight doesn't cast direct light but GI light for the moment.

Open the Irradiance map rollout and make the following changes:
Min/max=-4/-1
Hsph subdivs= 35

There will be less undersampling, and sample quality is increased because of more hsph subdivs.

Turn on 'show calc fase' so you can watch the progress of the IR map calculation. This will speed up the rendering psychologically :-)

As you can see, the caustics are already sharper. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 19. High quality GI settings

If you want a better GI solutions to increase caustics and shadow quality even more, you have a few options.

First is to increase min/max settings, to for example -2/1. For low resolutions like this, -2/1 is really high quality, don't go higher or you will loose the benefit of the undersampling.

You can also increase the hsph subdivs. This will calculate each taken sample better.

The clr threshold is also important, going from 0.4 to 0.3 will have a huge effect, but also on rendertimes... The dist threshold can be usefull here too (more samples where objects are close to each other, important for region under the foot of the glass)

So what settings are the best? A bit of everything :-)

The min max settings have the biggest impact. For this rendering I used the following IR map settings:
- min/max=-3/1
- Hsph subdivs= 40
- clr=0.35
- nrm=0.4
- dist=0.25

The caustics (especially these under the glass that lies down, look at the foot area) are much better now. But rendertime increased a lot... Usually you don't need this high settings, because no client will ever see the difference...

Note that the max setting of +1 is only used as long as the resolution stays at 430*480.

For resolutions from 640 to 800px, use -3/0 as the highest settings (-4/-1 for 1280 to 1600 etc...). I will explain the irradiance map behavior in another tutorial. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 20. Store with IR map option

As you can see, we need very high IR map settings to make sure shadows and caustics will be calculated accuratly.

As I said before, the shadow quality depends on IR map settings because of the 'store with IR map' option in the Vray light, treating the light as GI light instead of direct light.

By turning this option off, shadows will be raytraced, which results in very high quality. Rendertimes will be higher, but since quality now almost completely depend on the subdivs of the light, we can use lower IR map settings! So IR map calculation will speed up, and the actual rendering pass will slow down, resulting in +- the same overall rendertime, but better shadow detail.

When you use raytraced area shadows, note that the GI caustics will still be calculated by the IR map settings (the Vraylight is the only light being able to produce direct light AND GI caustics at the same time, making it an ideal light for product renderings). So we can't go too low on these settings or else the caustics will loose too much of their quality.

Turn off the 'store with IR map' option in the Vraylight, and set the subdivs to 30.

Go to the IR map settings and change min/max to -4/-1, and hsph subdivs to 35.

Render the image, look at the process. Note that during IR map calculation, everything looks darker, because the Vraylight doesn't cast GI light anymore. This IR map pass will go pretty fast, but the actual rendering pass will go slow because the direct light (and area shadows) need to be computed now also...

The result is very pleasing. Caustics are a bit less detailed, but this is compensated by the raytraced area shadows. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] 21. Final image

We will now render the image at a higher resolution.

Set the render output to 717*800px.

We want the same GI quality as in the previous image, but since the IR map settings are resolution dependant, we will need to make a small change. We kinda doubled the render resolution, so in order to have the same GI quality, you only need to lower both the min and max setting by 1. So set these at -5/-2. The tresholds and hsph subdivs are not resolution dependant so leave them at their current values.

To get rid of the last noise in the shadows and anti aliasing, go to the QMC sampler rollout and change the noise threshold to 0.002.

Render the image!

Click the image on the right to see the high resolution version. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]

---------- Post added at 08:24 PM ---------- Previous post was at 08:19 PM ----------

Before you start
This tutorial is a brief overview of what you will be able to do with Vray, one of the most popular rendering plugins for 3D Studio Max.

The Vray version used to create this tutorial is Vray 1.50.00. This is the version that requires the hardware lock (dongle) as a licensing system. Please do not email me with questions about this tutorial if you are not using this Vray version, since the answer to your question is most likely that you're using a different version.

Make sure you have basic 3D Studio Max knowledge too, I will not explain every little detail so you have to know how to use Max. For example things like the material editor, creating and manipulating objects, modifiers etc should all be familiar.
What is Vray?
As you probably already know, Vray is a render plugin. It's a plugin, which means that it adds a lot of functionality to an existing program. Vray's features mainly aim at creating photorealistic images, together with improving rendering speed. Currently, Vray exist for 3D Studio Max, Maya and Rhinoceros 3D. This tutorial is made with Vray for Max, but the plugins for the other packages are generally very similar.

Most of Vray's features can be found in Max's render settings dialog, but many smaller items are distributed across the complete program. For example Vray adds its own materials, light types, a fur generator, a toon style effect, a displacement modifier, etc...

Vray is created by Chaosgroup, a European company based in Bulgaria. Click [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] to visit their website.
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] Vray Features
You can read all of Vray's features on the official [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] . I will list some of the most important ones in the next paragraphs.
Vray Features - Full scene antialiasing
Antialising is directly related to image quality. It deals with smoothing out object edges, texture details, blurry reflections, area shadows etc... Take a look at the image on the righ to see the difference between antialiasing and no antialiasing.

Changing antialiasing settings have a huge effect on rendertimes, it can bring a render from 5 seconds to a few hours by altering a setting from 0.1 to 0.001.

With only a few settings you get full control over the complete image, which makes this perfect for changing from a quick preview render to a high quality final image.
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] Vray Features - Advanced materials
As I already said, Vray adds its own material types to 3DS Max. You have the choice between a normal Vray material, the vraylight material, VrayBlend material, Vray2sided material, VrayfastSSS and the vraymaterial wrapper. You can create every material you can imagine with just these types (or combination of these types or in combination with Max's texture maps).

The normal Vray material is the one you will be using most. With only this type you can create anything like glass, plastics, metals, wood, and so on.

The images on the right show a few of the many possibilities with Vray materials, created in just a few seconds. The top image is some kind of brushed metal, in the second one I turn two teapots into light emitters, and the third one is blurry transparant plastic or glass object.
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] Vray Features - Displacement mapping
Displacement mapping is mostly used to add fine detail to your object at rendertime. You can use any kind of map for the displacement, and vray will 'displace' your mesh according to the grayscale info in the map. For example black pixels will not be displaced, white pixels will have the highest displacement. This is similar as with bump maps, but with displacement the actual mesh is displaced, so even at the edges of your object you can see the 'bumps'. You can even use displacement to turn a flat plane into a rough mountain landscape!
The image on the right is the same object as the glass one from the previous step, but it is displaced with a cellular map. So without any modeling at all, the object suddenly becomes extremely detailed.
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] Vray Features - Physically accurate global illumination
Global illumination is one of Vray's strongest points, which is why many archviz people are using it. It's a term used for the correct calculation of how light behaves in the real world. When light hits objects, it gets partially absorbed, and partially bounced off again. In traditional renderers, this behavior is not calculated. When you add a light, it casts light onto the other objects and that's it, everything that is in shadow will be black (see first image on the right).
So you have to add more lights to brighten up these dark parts etc... In Vray, because light bounces of surfaces, the shadowed parts are not completly black, some of the bounced light will reach these parts to brighten it up. This makes up for extremely realistic lighting. The second image is with global illumination turned on. Notice that the light hits the teapot and floor, bounces of and illuminates each other. It even reveales some small teapots that were not visible at all in the first image!
You have the choice between various methods of calculating the global illumination, depending on the quality and speed you're after, or if it's a still or an animation you're creating.
Calculating global illumination is very heavy on the CPU, but Vray has loads of clever optimizations built in to speed things up. You have full control over the speed vs quality trade off.
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] Vray Features - Depth of field
Vray can also mimic real world camera properties, one of these is depth of field. Objects out of focus will become more blurry, and of course like everything else, you have full control over every property that defines the DOF. Vray even has a special camera, that will give you the same options as in real world camera's so you can control the image exposure and DOF with things like shutter speed, film ISO, aperture etc...
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] Vray Features - Fur generator
Vray fur is a special object type which lets you place fur strands on any type of geometry. The fur is not heavy on the viewport as it is generated at rendertime (like with the displacement map). Fur can be used for thins like hair, grass, cool looking trees, rugs or even a cactus.
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---------- Post added at 08:28 PM ---------- Previous post was at 08:24 PM ----------

Before you start

This tutorial tries to explain some basics about global illumination, and the different algorithms vray provides to calculate it. I will not go into detail here about every setting, it's just a global guide.

The Vray version used to create this tutorial is Vray 1.50.00. This is the version that requires the hardware lock (dongle) as a licensing system. Please do not email me with questions about this tutorial if you are not using this Vray version, since the answer to your question is most likely that you're using a different version.

Make sure you have basic 3D Studio Max knowledge too, I will not explain every little detail so you have to know how to use Max. For example things like the material editor, creating and manipulating objects, modifiers etc should all be familiar. What is GI?

GI is short for Global Illumination. Renderers that use global illumination algorithms take into account not only the light coming directly from light sources (=direct light), but also the light that is bounced of from all surfaces and all of the following light bounces untill infinity (=indirect light). This results in much more natural and photoreal lighting compared to traditional non GI renderers. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] Non GI rendering

On the right, a simple image with only one light, coming in fom the left. As you can see, the shadows are completely black and you hardly see the shape of the objects. Also note the shadow underneath the glass sphere, also black. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] GI - primary bounce

In reality, light keeps on bouncing around untill infinity. Each time a bounce occurs, the light loses a bit of energy, depending on the properties of the surface it hits. So after an infinite amount of bounces, the lights energy reaches zero. To calculate an infinite amount of light bounces would be crazy, so Vray has some ways to compensate for this. Also, the loss of energy has an exponential curve, so in fact the light energy fades out pretty quickly. This means that the effect of the primary bounce on the final lighting will be far greater than for example the 63rd bounce.

This is why Vray divides the indirect illumination into two main parts: primary and secondary bounces.

On the right, the same image now with GI turned on, only primary bounces. Note the shadows and the interior part are not black anymore. There are still very dark places, this is where the primary light bounces almost don't reach.
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] GI - secondary bounces

To further mimic real world lighting, we must enable the secondary bounces too. Calculating primary and secondary bounces is not an easy task. You have to imagine that a light ray from the direct light hits a surface, and bounces back in all directions. Let's say it scatters into 50 new rays, which are then primary bounces. These 50 rays again hit some surface, and scatter again in 50 new rays. So after only two bounces there are already 50*50=2500 rays flying around. And this is only frome 1 ray of the direct light. Of course Vray has some ways to limit the number of rays, together with very clever ways of finding out which rays are more important than others etc...

The images on the right shows the effect of the secondary bounces. As you can see, the second bounce has a big effect, the third one already a lot less, and so on. Even the jump from 4 to 12 bounces is almost nothing. [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] Primary bounces - Brute force
The easiest engine is the 'brute force'. As the name already suggests, it requires brute force to calculate :-) This method computes the GI in every single shaded point. So even with very flat surfaces where lighting is very even, every point will be calculated. This is of course very slow, but also very exact.
The image on the right is lit with Vray's skylight. Think of this as a real sky illuminating the scene. There is no sun, so it's a bit like a cloudy day, casting light evenly from all directions. This skylight is treated as primary bounce GI, so in this scene, there is no direct light. All the light (and thus also shadows) are calculated by the GI engine, which make the skylight perfect for testing the quality and speed of the engines!
I rendered the image on the right with the default values for the engine. As you can see, this is 8 subdivs. The secondary bounces are greyed out, since we disabled these for the tests. The subdivs value is the quality of the brute force GI. So more subdivs is more accurate calculations, less noisy image and of course slower render speed. I included the render time in all the images, click on it to enlarge!
The second image is with brute force subdivs set to 16. You can clearly see the noise is a lot less now, but rendertimes went from 23 to 56 seconds. Note that the subdivs value of 8 actually means 8*8=64, and 16 means 16*16=256. So take care when you want to increase quality! (This is true for all subdivs values inside Vray by the way.)
The third image is with subdivs=32. Notice how it's especially the noise inside the box that get's better now. Also note how defined the shadows are under the teapots and also the sphere. Even caustics are showing up underneath the glass sphere! Caustics apppear when light gets bundled by reflected and/or refracted light rays. Like in the old days when you used to burn ants with a magnifying glass from the bundled sunlight :-)
To summarize, if you have a good pc and enough time to wait, brute force is an easy and very high qualiy GI engine. The downside is that when you start using secondary bounces, especially on interior scenes where there is usually a lot of secondary GI light, that the brute force method will become extremely slow.
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] Primary bounces - Irradiance map
The irradiance map is Vray's answer to efficiently speed up GI calculations. Not all surfaces and regions in a scene have the same GI detail, for example on a flat plane without any objects, lighting will be very even in every point. But when the surface is very bumpy, and lots of small objects rest on it, the GI will be much more detailed: small shadows and varying light intensities all over the place.
Basically, the irradiance map calculations can find out which parts of the scene need accurate GI and which parts don't. This is controlled by various parameters that you can see in the screenshot on the right.
The result of all this, is a collection of points on the surfaces in the scene. Each point now has a given value for it's color (=light). Areas that are flat without much detail, will have points spaced far away from each other. Since lighting doesn't vary much between two points close together. But in more detailed areas, points will be placed much closer, for example in our image underneath the teapots, where there is variation on lighting (=shadows).
The image on the right is rendered with IR map as primary bounce. The second image shows how the IR map points are placed. You can clearly see there are less points in the background than for example in between the wall and the cylinders.
Note the rendertimes of the first image, and also how clean (=no noise) it is compared to the brute force GI renders. But on the other hand, the very fine detail is lost a little bit (enlarge images to see this better). The last image I used very low settings to better see the 'blurring' or loss of detail in the shadows. Now all objects seem to be floating because of the lack of detailed shadowing underneath them.
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] Primary bounces - Light cache
Light cache is a very fast way of computing GI. It's a bit special as it computes all bounces always. So if we put it in the primary bounces, it's actually computing all bounces... The first image is with default settings, and as you can see, it is much lighter than all the previous images. This is due to the extra bounces it computes. For a better explanation of how the light cache works, please read the vray manual: [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]

Compared to the IR map, it is a bit easier to setup. The most important value here is the again the subdivs. Don't compare it to the brute force subdivs, for the lightcache, you need much higher values. The second image is rendered with 2000 subdivs (instead of 1000). You can already see a big improvement in the GI detail.

If you turn on "show calc. phase" you will see the LC process being updated over time. This is a very effective way for evaluating lighting without having to wait for the render to complete.

The last render has 5000 subdivs, resulting in very good quality. Although it is possible to achieve good quality with LC only, it is mainly used for secondary bounces while you use IR map or brute force GI for the primary bounce.
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] [ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] Primary bounces - Photon map
Photon map is yet another way of computing a GI solution. However I never had the need to use this method. The other engines are in fact much easier to set up and to understand, so I wonder why this is still implemented.
For more info on this subject, I suggest you read the help files:
[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ]
GI engines - combinations
Although you can use any combination of engines for primary and secondary bounces, there are some really usefull ones. I will render some examples with the 3 most used combinations:
- primary = IR map and secondary = brute force
- primary = IR map and secondary = light cache
- primary = brute force and secondary = light cache
IR map and brute force
This combination is used a lot for scenes without too much secondary light. For example product renderings are usually made in some kind of studio setup, where an object is placed on a flat plane, lit by some large area lights and/or a skylight. Since most bounces fly off into the sky and therefore don't need further calculation, there are not much secondary bounces present. Most of the GI lighting is done by the primary bounces. The little secondary bounces are calculated by the exact brute force method. So with some good IR map settings, this results in high quality images with fast rendertimes. The biggest lighting effect even comes from direct lights, so even with some lower IR map settings the image is still very good, as the effect from the primary bounces isn't even that huge.

This method will however be slower for interior scenes, then you will be better off with the next combination.

[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] IR map and Light cache
When the amount of bounced light gets more prominent in your scene, the brute force method can become quite slow, especially when used for secondary bounces. The lightcache is ideal as a secondary bounces engine, since it's so fast. On top of that, when you use this combo, the LC is calculated first, and all the info from the LC is used for the calculation of the IR map. As a result, the IR map will be computed faster too.

When you're after extreme detail in your GI light, you're better off using the next combo, instead of increasing the IR map settings to extremes. Because then the IR map will become very slow too. So the IR map + LC is a good combo for relatively flat interior scenes.

[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] Brute force and Light cache
For very good quality images, this is the way to go. Of course a lot slower than the other combo's, but still not as slow as brute force + brute force would be. This can be a very good combo for high quality interiors, but also for exteriors, product scenes and last but not least, animations wih moving objects.

The IR map has many problems with moving objects, since it is an approximate method, so each frame will have a slightly varying lighting solution. This results in 'flickering' of the GI light in your animation. By using an exact method like brute force, you can remove the flickering. Usually animations are outdoor, and when indoor, it is rendered in two passes so it's not really an interior render. So then you're again in the situation like product renders, where there is not that much secondary bounces and the brute force + LC will be quite fast.

As you can see in the image on the right, the rendertime becomes very high. But note the shadows that the teapots are casting. It shows detail that is completely lost in the other renderings.

[ برای مشاهده لینک ، با نام کاربری خود وارد شوید یا ثبت نام کنید ] Conclusion
GI is great to produce realistic images, but it is always a struggle between image quality and detail versus rendertimes. Each engine has it's advantages, so it's important to try them all so you know when to use which engine. Especially the IR map has many settings to control, which can increase rendertimes a lot if you don't know what you're doing.
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