If you are starting this tutorial here, you will need to download the result of the previous section.

Add A Ground Plane

Create a Grid and scale it up to the horizon. Something around 1000 should do.

Assign Shaders to Robot and Floor

 

 

To assign the robot shaders, we will need to apply them to the groups inside the obj file. Enter the one_eyed_robot network and create a material node after the copy1.

 

Group - robot_eye_pupil  >  Material - /shop/robot_eye_pupil

Group - robot_eye_ball  >  Material - /shop/robot_eye_ball

Group - robot_body robot_eye_lid robot_eye_iris  >  Material - /shop/robot_body

 

Create An Arnold ROP

Now go to Outputs and tab-create an Arnold ROP. Leave it as default values for now though if you have an Arnold License, you might want to disable Skip License Check  in Properties > System.

 

Physical Sky as Light And Environment

Tab-create an Arnold Light and under the Light tab set Light Type to Skydome. Increase the light's Samples to 2. Change Color Type to Shader and click on the Arrow to the right of the Color Shader parameter.

 

 

To view the Physical Sky as a background, the vopnet inside the light must be connected to the Environment parameter of the Arnold ROP. This is under the Main tab.

 

Render the scene using your preferred context, and you should see something similar to below.

 

Add Shading Variety

Now to add the color variety. Enter the one_eyed_robot_network and select the copy1 node. Name Variable 2 to seed and set Value 2 to rand($PT + 65465). This is generating random seed value based on the point the robot is assigned to.

 

This seed value needs to be attached to each robot as an attribute that can be passed to the shader. Again, we will use the copy nodes stamp ability.

 

 

 

 

As this seed value will now be exported, we can use a User Data node to collect it and apply it in a shader network.

 

 

 

Go to the Arnold ROP and under Properties > Sampling, increase the AA Samples to 4 and Specular samples to 3.

 

Now render again to see a robot army of many colors!

 

You can download the result of this section below.