【OpenUSD】USD入門 その2：PythonでUSDを生成・操作してみる

set PYTHONPATH=[実行環境作成先のパス]\lib\python
set PATH=[実行環境作成先のパス]\lib

python [実行するPythonスクリプトパス].py

from pxr import Usd, UsdGeom

stage = Usd.Stage.CreateNew("usd/HelloWorld.usda")
UsdGeom.Xform.Define(stage, "/hello")
UsdGeom.Sphere.Define(stage, "/hello/world")
stage.GetRootLayer().Save()

#usda 1.0

def Xform "hello"
{
    def Sphere "world"
    {
        float3[] extent = [(-2, -2, -2), (2, 2, 2)]
        color3f[] primvars:displayColor = [(0, 0, 1)]
        double radius = 2
    }
}

set PYTHONPATH=[実行環境作成先のパス]\lib\python
set PATH=[実行環境作成先のパス]\lib

usdview [USDファイルパス]

from pxr import Usd, UsdGeom

# Set Default Prim
stage = Usd.Stage.Open("usd/HelloWorld.usda")
hello_prim = stage.GetPrimAtPath("/hello")
stage.SetDefaultPrim(hello_prim)
# Save Root Layer
stage.GetRootLayer().Save()
__print_root_layer(stage)

# Create Ref USD
ref_stage = Usd.Stage.CreateNew("usd/HelloWorld_Ref.usda")

# Ref Hello 1: Default Settings
ref_hello_1 = ref_stage.OverridePrim("/refHello1")
ref_hello_1.GetReferences().AddReference("./HelloWorld.usda")

# Ref Hello 2: Change Translate And Color Attr
ref_hello_2 = ref_stage.OverridePrim("/refHello2")
ref_hello_2.GetReferences().AddReference("./HelloWorld.usda")
ref_hello_2_xform = UsdGeom.Xformable(ref_hello_2)
UsdGeom.XformCommonAPI(ref_hello_2_xform).SetTranslate((4, 4, -4))
ref_hello_2_sphere = UsdGeom.Sphere.Get(ref_stage, "/refHello2/world")
ref_hello_2_sphere.GetDisplayColorAttr().Set([(1, 0, 0)])

# Save Root Layer
ref_stage.GetRootLayer().Save()

#usda 1.0
(
    defaultPrim = "hello"
)

def Xform "hello"
{
    def Sphere "world"
    {
        float3[] extent = [(-2, -2, -2), (2, 2, 2)]
        color3f[] primvars:displayColor = [(0, 0, 1)]
        double radius = 2
    }
}

#usda 1.0

over "refHello1" (
    prepend references = @./HelloWorld.usda@
)
{
}

over "refHello2" (
    prepend references = @./HelloWorld.usda@
)
{
    double3 xformOp:translate = (4, 4, -4)
    uniform token[] xformOpOrder = ["xformOp:translate"]

    over "world"
    {
        color3f[] primvars:displayColor = [(1, 0, 0)]
    }
}

from pxr import Usd, UsdGeom

# Create Base USD
stage = Usd.Stage.CreateNew("usd/HelloWorld_VariantSets.usda")
xform = UsdGeom.Xform.Define(stage, "/hello")
sphere = UsdGeom.Sphere.Define(stage, "/hello/world")
stage.GetRootLayer().Save()

# Create VariantSets
hello_prim = stage.GetPrimAtPath("/hello")
shading_variant = hello_prim.GetVariantSets().AddVariantSet("shadingVariant")
shading_variant.AddVariant("red")
shading_variant.AddVariant("green")
shading_variant.AddVariant("blue")

# Set VariantSets Values
sphere_schema = UsdGeom.Sphere(sphere)
color_attr = sphere_schema.GetDisplayColorAttr()
shading_variant.SetVariantSelection("red")
with shading_variant.GetVariantEditContext():
    color_attr.Set([(1, 0, 0)])
shading_variant.SetVariantSelection("green")
with shading_variant.GetVariantEditContext():
    color_attr.Set([(0, 1, 0)])
shading_variant.SetVariantSelection("blue")
with shading_variant.GetVariantEditContext():
    color_attr.Set([(0, 0, 1)])
shading_variant.ClearVariantSelection()

# Save Root Layer
stage.GetRootLayer().Save()

#usda 1.0

def Xform "hello" (
    prepend variantSets = "shadingVariant"
)
{
    def Sphere "world"
    {
    }
    variantSet "shadingVariant" = {
        "blue" {
            over "world"
            {
                color3f[] primvars:displayColor = [(0, 0, 1)]
            }

        }
        "green" {
            over "world"
            {
                color3f[] primvars:displayColor = [(0, 1, 0)]
            }

        }
        "red" {
            over "world"
            {
                color3f[] primvars:displayColor = [(1, 0, 0)]
            }

        }
    }
}

from pxr import Kind, Sdf, Usd, UsdGeom, UsdShade

stage = Usd.Stage.CreateNew("usd/SimpleShading.usda")
UsdGeom.SetStageUpAxis(stage, UsdGeom.Tokens.y)

# Create Context
model_root = UsdGeom.Xform.Define(stage, "/TexModel")
Usd.ModelAPI(model_root).SetKind(Kind.Tokens.component)

# Create Billboard Mesh
half_width = 430
half_height = 150
billboard = UsdGeom.Mesh.Define(stage, "/TexModel/card")
billboard.CreatePointsAttr(
    [
        (-half_width, -half_height, 0),
        (half_width, -half_height, 0),
        (half_width, half_height, 0),
        (-half_width, half_height, 0),
    ]
)
billboard.CreateFaceVertexCountsAttr([4])
billboard.CreateFaceVertexIndicesAttr([0, 1, 2, 3])
billboard.CreateExtentAttr(
    [(-half_width, -half_height, 0), (half_width, half_height, 0)]
)
texcoords = UsdGeom.PrimvarsAPI(billboard).CreatePrimvar(
    "st", Sdf.ValueTypeNames.TexCoord2fArray, UsdGeom.Tokens.varying
)
texcoords.Set([(0, 0), (1, 0), (1, 1), (0, 1)])

# Create Shader
shader = UsdShade.Shader.Define(stage, "/TexModel/boardMat/PBRShader")
shader.CreateIdAttr("UsdPreviewSurface")
shader.CreateInput("roughness", Sdf.ValueTypeNames.Float).Set(0.6)
shader.CreateInput("metallic", Sdf.ValueTypeNames.Float).Set(0.0)

# Create Material
material = UsdShade.Material.Define(stage, "/TexModel/boardMat")
material.CreateSurfaceOutput().ConnectToSource(shader.ConnectableAPI(), "surface")

# Add Texture
st_reader = UsdShade.Shader.Define(stage, "/TexModel/boardMat/stReader")
st_reader.CreateIdAttr("UsdPrimvarReader_float2")
st_input = material.CreateInput("frame:stPrimvarName", Sdf.ValueTypeNames.Token)
st_input.Set("st")
st_reader.CreateInput("varname", Sdf.ValueTypeNames.Token).ConnectToSource(st_input)

texture_sampler = UsdShade.Shader.Define(stage, "/TexModel/boardMat/diffuseTexture")
texture_sampler.CreateIdAttr("UsdUVTexture")
texture_sampler.CreateInput("file", Sdf.ValueTypeNames.Asset).Set(
    "./tex/usd_test.png"
)
texture_sampler.CreateInput("st", Sdf.ValueTypeNames.Float2).ConnectToSource(
    st_reader.ConnectableAPI(), "result"
)
texture_sampler.CreateOutput("rgb", Sdf.ValueTypeNames.Float3)

shader.CreateInput("diffuseColor", Sdf.ValueTypeNames.Color3f).ConnectToSource(
    texture_sampler.ConnectableAPI(), "rgb"
)

# Assign Material
billboard.GetPrim().ApplyAPI(UsdShade.MaterialBindingAPI)
UsdShade.MaterialBindingAPI(billboard).Bind(material)

# Save Stage
stage.Save()

#usda 1.0
(
    upAxis = "Y"
)

def Xform "TexModel" (
    kind = "component"
)
{
    def Mesh "card" (
        prepend apiSchemas = ["MaterialBindingAPI"]
    )
    {
        float3[] extent = [(-430, -150, 0), (430, 150, 0)]
        int[] faceVertexCounts = [4]
        int[] faceVertexIndices = [0, 1, 2, 3]
        rel material:binding = </TexModel/boardMat>
        point3f[] points = [(-430, -150, 0), (430, -150, 0), (430, 150, 0), (-430, 150, 0)]
        texCoord2f[] primvars:st = [(0, 0), (1, 0), (1, 1), (0, 1)] (
            interpolation = "varying"
        )
    }

    def Material "boardMat"
    {
        token inputs:frame:stPrimvarName = "st"
        token outputs:surface.connect = </TexModel/boardMat/PBRShader.outputs:surface>

        def Shader "PBRShader"
        {
            uniform token info:id = "UsdPreviewSurface"
            color3f inputs:diffuseColor.connect = </TexModel/boardMat/diffuseTexture.outputs:rgb>
            float inputs:metallic = 0
            float inputs:roughness = 0.6
            token outputs:surface
        }

        def Shader "stReader"
        {
            uniform token info:id = "UsdPrimvarReader_float2"
            token inputs:varname.connect = </TexModel/boardMat.inputs:frame:stPrimvarName>
            float2 outputs:result
        }

        def Shader "diffuseTexture"
        {
            uniform token info:id = "UsdUVTexture"
            asset inputs:file = @./tex/usd_test.png@
            float2 inputs:st.connect = </TexModel/boardMat/stReader.outputs:result>
            float3 outputs:rgb
        }
    }
}