void Start()
{
InitUsd.Initialize();
m_lastTime = m_usdTime;
if (string.IsNullOrEmpty(m_usdFile))
{
m_usdFile = Path.Combine(PackageUtils.GetCallerRelativeToProjectFolderPath(), K_DEFAULT_MESH);
}
}
void Start()
{
var asset = GetComponent <UsdAsset>();
if (string.IsNullOrEmpty(asset.usdFullPath))
{
asset.usdFullPath = Path.Combine(PackageUtils.GetCallerRelativeToProjectFolderPath(), K_DEFAULT_MESH);
}
}
//
// Start generates a USD scene procedurally, containing a single cube with a material, shader
// and texture bound. It then inspects the cube to discover the material. A Unity material is
// constructed and the parameters are copied in a generic way. Similarly, the texture is
// discovered and loaded as a Unity Texture2D and bound to the material.
//
// Also See: https://docs.unity3d.com/Manual/MaterialsAccessingViaScript.html
//
void Start()
{
// Get the current local path
m_localPath = PackageUtils.GetCallerRelativeToProjectFolderPath();
// Create a scene for this test, but could also be read from disk.
Scene usdScene = CreateSceneWithShading();
// Read the material and shader ID.
var usdMaterial = new MaterialSample();
string shaderId;
// ReadMaterial was designed for Unity and assumes there is one "surface" shader bound.
if (!MaterialSample.ReadMaterial(usdScene, kCubePath, usdMaterial, out shaderId))
{
throw new System.Exception("Failed to read material");
}
// Map the shader ID to the corresponding Unity/USD shader pair.
ShaderPair shader;
if (shaderId == null || !m_shaderMap.TryGetValue(shaderId, out shader))
{
throw new System.Exception("Material had no surface bound");
}
//
// Read and process the shader-specific parameters.
//
// UsdShade requires all connections target an attribute, but we actually want to deserialize
// the entire prim, so we get just the prim path here.
var shaderPath = new pxr.SdfPath(usdMaterial.surface.connectedPath).GetPrimPath();
usdScene.Read(shaderPath, shader.usdShader);
//
// Construct material & process the inputs, textures, and keywords.
//
var mat = new UnityEngine.Material(shader.unityShader);
// Apply material keywords.
foreach (string keyword in usdMaterial.requiredKeywords ?? new string[0])
{
mat.EnableKeyword(keyword);
}
// Iterate over all input parameters and copy values and/or construct textures.
foreach (var param in shader.usdShader.GetInputParameters())
{
if (!SetMaterialParameter(mat, param.unityName, param.value))
{
throw new System.Exception("Incompatible shader data type: " + param.ToString());
}
}
foreach (var param in shader.usdShader.GetInputTextures())
{
if (string.IsNullOrEmpty(param.connectedPath))
{
// Not connected to a texture.
continue;
}
// Only 2D textures are supported in this example.
var usdTexture = new Texture2DSample();
// Again, we want the prim path, not the attribute path.
var texturePath = new pxr.SdfPath(param.connectedPath).GetPrimPath();
usdScene.Read(texturePath, usdTexture);
// This example also only supports explicit sourceFiles, they cannot be connected.
if (string.IsNullOrEmpty(usdTexture.sourceFile.defaultValue))
{
continue;
}
// For details, see: https://docs.unity3d.com/Manual/MaterialsAccessingViaScript.html
foreach (string keyword in param.requiredShaderKeywords)
{
mat.EnableKeyword(keyword);
}
var data = System.IO.File.ReadAllBytes(usdTexture.sourceFile.defaultValue);
var unityTex = new Texture2D(2, 2);
unityTex.LoadImage(data);
mat.SetTexture(param.unityName, unityTex);
Debug.Log("Set " + param.unityName + " to " + usdTexture.sourceFile.defaultValue);
unityTex.Apply(updateMipmaps: true, makeNoLongerReadable: false);
}
//
// Create and bind the geometry.
//
// Create a cube and set the material.
// Note that geometry is handled minimally here and is incomplete.
var cubeSample = new CubeSample();
usdScene.Read(kCubePath, cubeSample);
var go = GameObject.CreatePrimitive(PrimitiveType.Cube);
go.transform.SetParent(transform, worldPositionStays: false);
go.transform.localScale = Vector3.one * (float)cubeSample.size;
m_cube = transform;
go.GetComponent <MeshRenderer>().material = mat;
}