// Returns the guid found on this material's vert or frag shader, or Empty on failure.
// This Guid represents the template from which a pbr material was created.
// For example, BasePbrOpaqueDoubleSided.
private static Guid ParseGuidFromShader(Gltf1Material material)
{
var technique = material.techniquePtr;
if (technique == null)
{
return(Guid.Empty);
}
var program = technique.programPtr;
if (program == null)
{
return(Guid.Empty);
}
var shader = program.vertexShaderPtr ?? program.fragmentShaderPtr;
if (shader == null)
{
return(Guid.Empty);
}
var match = kTiltBrushShaderRegex.Match(shader.uri);
if (match.Success)
{
return(new Guid(match.Groups[1].Value));
}
else
{
return(Guid.Empty);
}
}
/// Returns a BrushDescriptor given a gltf material, or null if not found.
/// If the material is an instance of a template, the descriptor for that
/// will be returned.
public static BrushDescriptor LookupBrushDescriptor(GltfMaterialBase gltfMaterial)
{
Guid guid = ParseGuidFromMaterial(gltfMaterial);
if (guid == Guid.Empty)
{
return(null);
}
else
{
BrushDescriptor desc;
PtSettings.Instance.brushManifest.BrushesByGuid.TryGetValue(
guid, out desc);
if (desc == null)
{
// Maybe it's templated from a pbr material; the template guid
// can be found on the shader.
Gltf1Material gltf1Material = gltfMaterial as Gltf1Material;
if (gltf1Material == null)
{
Debug.LogErrorFormat("Unexpected: glTF2 Tilt Brush material");
return(null);
}
Guid templateGuid = ParseGuidFromShader((Gltf1Material)gltfMaterial);
PtSettings.Instance.brushManifest.BrushesByGuid.TryGetValue(
templateGuid, out desc);
}
return(desc);
}
}
/// <summary>
/// Converts the given glTF1 material to a new Unity material.
/// This is only possible if the passed material is a Tilt Brush "PBR" material
/// squeezed into glTF1.
/// </summary>
/// <param name="gltfMat">The glTF1 material to convert.</param>
/// <returns>The result of the conversion, or null on failure.</returns>
private UnityMaterial?ConvertGltf1Material(Gltf1Material gltfMat)
{
Guid instanceGuid = ParseGuidFromMaterial(gltfMat);
Guid templateGuid = ParseGuidFromShader(gltfMat);
BrushDescriptor desc;
if (!PtSettings.Instance.brushManifest.BrushesByGuid.TryGetValue(templateGuid, out desc))
{
// If they are the same, there is no template/instance relationship.
if (instanceGuid != templateGuid)
{
Debug.LogErrorFormat("Unexpected: cannot find template material {0} for {1}",
templateGuid, instanceGuid);
}
return(null);
}
TiltBrushGltf1PbrValues tbPbr = gltfMat.values;
// The default values here are reasonable fallbacks if there is no tbPbr
Gltf2Material.PbrMetallicRoughness pbr = new Gltf2Material.PbrMetallicRoughness();
if (tbPbr != null)
{
if (tbPbr.BaseColorFactor != null)
{
pbr.baseColorFactor = tbPbr.BaseColorFactor.Value;
}
if (tbPbr.MetallicFactor != null)
{
pbr.metallicFactor = tbPbr.MetallicFactor.Value;
}
if (tbPbr.RoughnessFactor != null)
{
pbr.roughnessFactor = tbPbr.RoughnessFactor.Value;
}
if (tbPbr.BaseColorTexPtr != null)
{
pbr.baseColorTexture = new Gltf2Material.TextureInfo {
index = -1,
texCoord = 0,
texture = tbPbr.BaseColorTexPtr
};
}
// Tilt Brush doesn't support metallicRoughnessTexture (yet?)
}
return(CreateNewPbrMaterial(desc.Material, pbr));
}
