Brazil Rendering System Tutorials

Playing with Glass

In this tutorial we'll learn something useful to build a good glass and render with Brazil r/s. You can find the file here
(Brazil public version 0.4.53 - Max 4.2)


1. The Background.

#1 First of all draw a line with a L shape in the left view, then go to the modify panel and select Edit Spline from the modifier list. Now select vertex in the Selection rollout and go to the left view.
#2 Select the Corner vertex and in the rollout panel, press fillet and increase to a good value to obtain a cool curve.
Now it's time to extrude: select Extrude in the modifier selection and, after cecking "generate mapping Coords." under Parameters, put a value (i.e. 500) in the Amount value. Remember to select "Force 2 sided", in the Perspective viewport configuration ( Right click over "perspective" in the perspective view - Configure - Rendering option) .
Now pan the perspective view to center the image (Ctrl+P).
Go down to image #6 for a full view.
 

 



2. The Glass.

#3 #4 #5
in the front view draw a line like the image (i used 23 vertices. Keep attention to have a very thiny cup), under selection rollout in the modifier panel select "vertex" and scrolling down to "Fillet", check it. Go vertex by vertex and fillet them but not the ones in the red circle of the image. You have to transform these 2 vertices from Corner to Smooth (right click on them) and move a little to position them in the right way.
       
#6 And now, let's choose LATHE modifier in the modifier list.
In the parameters put 32 Segments (higher values means smoother but expensive) and Min under "Align", then Check "Generate Mapping Coords.".





3. Bright Cards , scene composition and Camera.
     
#7   In order to have nice reflections and a kind of light, build three rectangles around the glass and rotate them toward the upper side of the glass.Try to stay as near as possible to the glass.
One small bright card has been put besides the place where we'll put the camera to give frontal reflections and don't mask the camera itself.
Then i converted them into Editable meshes by right clicking on them and selecting "Convert to editable mesh".
The Scene:
In the left view, move the L line used for background in order to have the glass standing right on it. Then select the upper vertices and move to a higher position. (go down to Edit Spline in the modifier panel and select the upper vertex).
Then move the background like in this final image.
    The camera:
Place a target camera in front of the glass. In this example i put it a little higher and the target under the cup.
Look at the image for the position.
Press Shift+R and in the Render panel, under Common Parameters,Output Size, choose Width:250, Height:400.
In the perspective view, press "C" to enable Camera view, right click in the upper left corner and check Show Safe Frame. The viewport now shows what will be the render field.

4. Materials.

Glass:
Click "M" and open MTL editor.
Get a new material by pressing the first icon on the left (sphere with arrow) and select Brazil Test MTL.
Under basic Parameters check 2 sided.
Click on Transparency Color and put 244,244,244. You can choose another color to have different glass color.
Click on the right of Reflect color and choose Falloff map by double clicking.
Under Falloff parameters choose Falloff Type: Fresnel.
Now return to Parent (2nd button on the right).
Specular Level 190
Glossiness 60
You can play with these two parameters till you reach the best result for you, try with 0/0 too.
Under Raytracer Controls check Prevent Internal Reflections to get a speeder rendering. (If you want transparent shadows in a new image, check Transparent Shadows too and add a light with raytraced Shadows).
Now select the glass and Assign material to selection (3rd button on the left).


  

Background:
get a standard material, 2 sided, black Ambient an Specular,Diffuse=234,241,255,Specular Level an Glossiness = 0.
Select the background line in the left view and assign this material.

  

Bright Cards:
Put an output map into diffuse slot of a standard material and increase RGB level to 3. Put an instance of this map into Self-illumination slot. Select the boxes and assign this material.

5. Rendering.

Press Shift+R and open render dialog:
under Current renderers choose Brazil 0.4.53.
Choose Force 2 sided under Common Parameters/Options.
Now in Brazil Sampling Params/ Image Sampling Control, put Min Samples=0 and Max Samples=2. These values make your image pretty good and antialiased.
If you want a fast preview but aliased, put Min=-2;Max=0.


Hit Render and enjoy.
Now you can play with some interesting things:  


 
 

Only Direct Illumination
This is the result with previous settings. Try also after hiding bright cards. The fastest way.

  
HDRI reflections
Hide bright cards and apply a HDR image in the Environment Map (Rendering/Environment/Common Parameters/Environment map.
For settings read this tutorial by clicking HDRI tutorial.
(in this scene I used White point 8/256, Spherical coordinates, RGB output 256 but try also with 150).
  
Global Illumination
Hit Shift+R, and under Brazil:Luma Server Parameters enable Secondary illumination. I didn't use Skylight for this test because i supposed it was not an outdoor scene.
Under Global Illumination, choose Shade Rate Min=-3; Max=0. Remember that undersampling speed up renderings. Then i left Sampling Control Rate=15;Bounces=1.
You can increase Rate and Bounces for better results (less grainy) but consider that it could increase Rendering times.
This image could take a lot of time to render depending on your Machine.