Maya: Raytracing Tutorial, Wine Glass

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glass.jpg

Revolve a wine glass shape, place it on a plane.

Turn off Color Management:
Select Windows->Settings/Preferences->Preferences
Select Color Management
Uncheck Enable Color Management
Select Save

P
ress this Render Settings icon upper right or middle  srender_settings 
(Windows->Rendering Editors->Render Settings...)

Rendering in Arnold
Raytracing is a type of shadow rendering where the path of individual  light rays are calculated from their source (the light) to their  destination (the camera). It can produce soft and transparent shadows.
Raytracing is done automatically with Arnold

hypershade   Windows->Rendering Editors->Hypershade
I
n the hypershade window, click on
aiStandard Surface under the Arnold Shader node.

Select the wine glass from the scene.
Check off Opaque under the Arnold drop-down in the Attribute Editor

Click the 
aiStandard Surface shader ball.
Double click the shader ball to see the attributes.
Under Base set Weight to 0.8 ans Metalness to 0.15
Under Specular, set Roughness to 0.1

Under Specular, set IOR (Index of Refraction) to 1.5, or 1.1 for thin glass
Under Transmission set Weight to .1

Select a model.
Use the right mouse key over the shader ball to bring up the marking menu, select
Assign Material to Selection

To get highlights, use an Area light with a tall and thin scale, following the proportions of the wine glass.
Under the arnold attributes of this light, set the Exposure to 11

Click on the
Render Settings
icon upper right or middle  srender_settings 
Under Arnold Renderer
tab:
Change SSS to 6 and AA to 5


Click on the  renderbutton.jpg   render in new window button located at the top of the screen.
Note:
When rendering transparent and  refractive surfaces in Arnold, the normals of the geometry need to face in the right direction.



Rendering in Maya Software

Change Rendering Using to Maya Software
Under the Common tab:
Under the Image File Output
arrow:
Choose Image format: Tiff

Under Maya Software tab:
Under Raytracing Quality
    
Check  Raytracing
    
Input Reflections 1
    
Input Refractions 10
    
Input Shadows 2
    
Input Bias .2 This will make round objects look less jaggy.


Do some test renders with raytracing before you make the glass transparent to get the shadows where you want them.

Find a photograph of a glass you like for reference.


hypershade   Windows->Rendering Editors->Hypershade
In the hypershade window, click on
aiStandard Surface under the Arnold Shader node.

Select one or more objects from the scene.

Click the 
aiStandard Surface
shader ball.
Double click the shader ball to see the attributes.
Adjust Color to black.
Adjust Transparency, double click on the black color box to bring up the menu.
    
In HSV mode
    
input .9 as the value (V)

Under Specular Shading:
Input Cosine Power 100
Djust Specular Color to white
Input Reflectivity .2

Under Raytrace Options:
Check Refractions
Input Refractive Index 1.3
Input Refraction Limit 10
Input Surface Thickness  .4
Input Reflection Limit 1

Assign the shader to an object in the scene.

Click on the  renderbutton.jpg   render in new window button located at the top of the screen.