Blender 3.1 で export されたネットワークを仮定します.
def Xform "Cube"
{
matrix4d xformOp:transform = ( (1, 0, 0, 0), (0, 1, 0, 0), (0, 0, 1, 0), (-1.1853550672531128, 0, 1.9550952911376953, 1) )
uniform token[] xformOpOrder = ["xformOp:transform"]
def Mesh "Cube"
{
uniform bool doubleSided = 1
int[] faceVertexCounts = [4, 4, 4, 4, 4, 4]
int[] faceVertexIndices = [0, 4, 6, 2, 3, 2, 6, 7, 7, 6, 4, 5, 5, 1, 3, 7, 1, 0, 2, 3, 5, 4, 0, 1]
rel material:binding = </_materials/Material>
normal3f[] normals = [(0, 0, 1), (0, 0, 1), (0, 0, 1), (0, 0, 1), (0, -1, 0), (0, -1, 0), (0, -1, 0), (0, -1, 0), (-1, 0, 0), (-1, 0, 0), (-1, 0, 0), (-1, 0, 0), (0, 0, -1), (0, 0, -1), (0, 0, -1), (0, 0, -1), (1, 0, 0), (1, 0, 0), (1, 0, 0), (1, 0, 0), (0, 1, 0), (0, 1, 0), (0, 1, 0), (0, 1, 0)] (
interpolation = "faceVarying"
)
point3f[] points = [(1, 1, 1), (1, 1, -1), (1, -1, 1), (1, -1, -1), (-1, 1, 1), (-1, 1, -1), (-1, -1, 1), (-1, -1, -1)]
texCoord2f[] primvars:UVMap = [(0.625, 0.5), (0.875, 0.5), (0.875, 0.75), (0.625, 0.75), (0.375, 0.75), (0.625, 0.75), (0.625, 1), (0.375, 1), (0.375, 0), (0.625, 0), (0.625, 0.25), (0.375, 0.25), (0.125, 0.5), (0.375, 0.5), (0.375, 0.75), (0.125, 0.75), (0.375, 0.5), (0.625, 0.5), (0.625, 0.75), (0.375, 0.75), (0.375, 0.25), (0.625, 0.25), (0.625, 0.5), (0.375, 0.5)] (
interpolation = "faceVarying"
)
uniform token subdivisionScheme = "none"
}
}
def "_materials"
{
def Material "Material"
{
token outputs:surface.connect = </_materials/Material/preview/Principled_BSDF.outputs:surface>
def Scope "preview"
{
def Shader "Principled_BSDF"
{
uniform token info:id = "UsdPreviewSurface"
float inputs:clearcoat = 0
float inputs:clearcoatRoughness = 0.03
float3 inputs:diffuseColor.connect = </_materials/Material/preview/Image_Texture.outputs:rgb>
float inputs:ior = 1.45
float inputs:metallic = 0
float inputs:opacity = 1
float inputs:roughness = 0.4
float inputs:specular = 0.5
token outputs:surface
}
def Shader "Image_Texture"
{
uniform token info:id = "UsdUVTexture"
asset inputs:file = @.\textures\checkerboard.png@
token inputs:sourceColorSpace = "sRGB"
float2 inputs:st.connect = </_materials/Material/preview/uvmap.outputs:result>
float3 outputs:rgb
}
def Shader "uvmap"
{
uniform token info:id = "UsdPrimvarReader_float2"
token inputs:varname = "UVMap"
float2 outputs:result
}
}
}
}
GeomMesh から
materialBinding でどのマテリアルを使うかを調べます.
Material
基本は Shader のコンテナとの理解
シェーダの toplevel? を outputs:surface で指定.
Texture UV coordinates
UsdUvTexture では inputs.st に PrimvarReader をつなぐ.
ちょっとややこしいが, 実際の UV 座標データは, UsdPrimvarReader_float2 ノードの inputs:varname を見て GeomMesh 側の primvars:${varname} を見るようにする.