tinyusdz/tests/usda/usdlux_basic_lights.usda

#usda 1.0
(
    doc = "Basic UsdLux light types test - Point, Directional, Rect, Disk, Cylinder, Dome"
    defaultPrim = "World"
    metersPerUnit = 1
    upAxis = "Y"
)

def Xform "World"
{
    def Scope "Lights"
    {
        # 1. Point Light (Sphere Light) - Omnidirectional
        def SphereLight "KeyLight"
        {
            color3f inputs:color = (1.0, 0.95, 0.85)
            float inputs:intensity = 100.0
            float inputs:exposure = 1.0
            float inputs:radius = 0.5
            bool inputs:normalize = true

            # Shadow properties
            bool inputs:shadow:enable = true
            color3f inputs:shadow:color = (0.0, 0.0, 0.0)

            double3 xformOp:translate = (-3, 4, 3)
            uniform token[] xformOpOrder = ["xformOp:translate"]
        }

        # 2. Directional Light (Distant Light) - Sun-like
        def DistantLight "SunLight"
        {
            color3f inputs:color = (1.0, 1.0, 0.95)
            float inputs:intensity = 50.0
            float inputs:exposure = 0.5
            float inputs:angle = 0.53  # Sun's angular diameter in degrees

            # Enable color temperature
            bool inputs:enableColorTemperature = true
            float inputs:colorTemperature = 5800  # Sun temperature

            double3 xformOp:rotateXYZ = (-45, 30, 0)
            uniform token[] xformOpOrder = ["xformOp:rotateXYZ"]
        }

        # 3. Rect Light - Area light
        def RectLight "SoftBox"
        {
            color3f inputs:color = (0.9, 0.95, 1.0)
            float inputs:intensity = 200.0
            float inputs:width = 2.0
            float inputs:height = 1.5
            bool inputs:normalize = false

            double3 xformOp:translate = (0, 3, 5)
            double3 xformOp:rotateXYZ = (-30, 0, 0)
            uniform token[] xformOpOrder = ["xformOp:translate", "xformOp:rotateXYZ"]
        }

        # 4. Disk Light - Circular area light
        def DiskLight "RimLight"
        {
            color3f inputs:color = (1.0, 0.9, 0.8)
            float inputs:intensity = 150.0
            float inputs:radius = 0.75

            double3 xformOp:translate = (4, 2, -2)
            double3 xformOp:rotateXYZ = (0, -135, 0)
            uniform token[] xformOpOrder = ["xformOp:translate", "xformOp:rotateXYZ"]
        }

        # 5. Cylinder Light with shaping (Spotlight)
        def CylinderLight "Spotlight"
        {
            color3f inputs:color = (1.0, 1.0, 1.0)
            float inputs:intensity = 300.0
            float inputs:radius = 0.2
            float inputs:length = 0.5

            # Shaping for spotlight cone
            float inputs:shaping:cone:angle = 45.0
            float inputs:shaping:cone:softness = 0.2

            # Shadow properties
            bool inputs:shadow:enable = true
            float inputs:shadow:falloff = 1.0

            double3 xformOp:translate = (0, 5, 0)
            double3 xformOp:rotateXYZ = (-90, 0, 0)
            uniform token[] xformOpOrder = ["xformOp:translate", "xformOp:rotateXYZ"]
        }

        # 6. Dome Light - Environment lighting
        def DomeLight "EnvironmentLight"
        {
            color3f inputs:color = (0.4, 0.5, 0.6)
            float inputs:intensity = 0.5
            float inputs:exposure = -1.0

            # Optional: Reference to HDR environment map
            # asset inputs:texture:file = @./environment.hdr@
            token inputs:texture:format = "latlong"
        }
    }

    # Reference geometry to show lighting
    def Xform "Geometry"
    {
        def Sphere "TestSphere"
        {
            double radius = 1.0
            double3 xformOp:translate = (0, 1, 0)
            uniform token[] xformOpOrder = ["xformOp:translate"]
        }

        def Mesh "GroundPlane"
        {
            int[] faceVertexCounts = [4]
            int[] faceVertexIndices = [0, 1, 2, 3]
            point3f[] points = [(-10, 0, -10), (10, 0, -10), (10, 0, 10), (-10, 0, 10)]
            normal3f[] normals = [(0, 1, 0), (0, 1, 0), (0, 1, 0), (0, 1, 0)] (
                interpolation = "vertex"
            )
        }
    }
}