'
' This example demonstrates setting a parameter on a shader so that it uses 
' two different projections depending on which item it applies to. In this
' case, we will create one projection for the cube and another for the sphere
' and then tell the shader to use the CubeProjection on the cube and the
' SphereProjection on the sphere.
'
NewScene , false
' Get the default pass
Set oDefPass = GetValue( "Passes.Default_Pass" )
' Create a cube and a sphere
CreatePrim "Cube", "MeshSurface"
CreatePrim "Sphere", "MeshSurface"
Translate "sphere", 5.987, 0.039, -0.004, siRelative, siView, siObj, siXYZ
' Create an XZ texture projection on the object
CreateProjection "cube,sphere", "siTxtPlanarXZ", _
        "siTxtDefaultPlanarXY", , "WrongProjection"
' Create XY texture projections on the objects, named "CubeProjection" 
' and "SphereProjection"
CreateProjection "cube", "siTxtPlanarXY", _
        "siTxtDefaultPlanarXY", , "CubeProjection"
CreateProjection "sphere", "siTxtPlanarXY", _
        "siTxtDefaultPlanarXZ", , "SphereProjection"
' Put the cube and sphere in a group, put a material on it, with 
' an image attached to diffuse.
ToggleSelection "cube"
CreateGroup
ApplyShader
SIApplyShaderToCnxPoint "Image", "sphere.Material.Phong.diffuse"
' Now render one frame of the scene to see the effect  
' (the default image was plunked directly on the top of the 
' cube and sphere)
RenderPasses oDefPass, 1, 1
' At this point, the image shader will, by default, choose the 
' texture projection named "WrongProjection".  We want to tell 
' the image shader that on the cube, it should use "CubeProjection", 
' and on the sphere, it should use "SphereProjection".  This 
' means that the parameter is instance-specific, so we use 
' the SetInstanceDataValue command
' This line sets the parameter "tspace_id" to be "SphereProjection" 
' for the object "sphere"
SetInstanceDataValue "sphere", _
        "Group.Material.Phong.Image.tspace_id", "SphereProjection"
' This line sets the parameter "tspace_id" to be "CubeProjection" 
' for the object "cube"
SetInstanceDataValue "cube", _
        "Group.Material.Phong.Image.tspace_id", "CubeProjection"
' Now render one frame of the scene to see the effect 
' (the default image was applied to the visible area of the 
' cube and sphere)
RenderPasses oDefPass, 1, 1