/// <summary>
/// Converts the given GLTF 2 material to a Unity Material.
/// This is "best effort": we only interpret SOME, but not all GLTF material parameters.
/// We try to be robust, and will always try to return *some* material rather than fail,
/// even if crucial fields are missing or can't be parsed.
/// </summary>
/// <param name="gltfMat">The GLTF 2 material to convert.</param>
/// <returns>The result of the conversion</returns>
private UnityMaterial?ConvertGltf2Material(Gltf2Material gltfMat)
{
Material baseMaterial; {
string alphaMode = gltfMat.alphaMode == null ? null : gltfMat.alphaMode.ToUpperInvariant();
switch (alphaMode)
{
case Gltf2Material.kAlphaModeOpaque:
baseMaterial = gltfMat.doubleSided
? TbtSettings.Instance.m_BasePbrOpaqueDoubleSidedMaterial
: TbtSettings.Instance.m_BasePbrOpaqueSingleSidedMaterial;
break;
case Gltf2Material.kAlphaModeBlend:
baseMaterial = gltfMat.doubleSided
? TbtSettings.Instance.m_BasePbrBlendDoubleSidedMaterial
: TbtSettings.Instance.m_BasePbrBlendSingleSidedMaterial;
break;
default:
Debug.LogWarning($"Not yet supported: alphaMode={alphaMode}");
goto case Gltf2Material.kAlphaModeOpaque;
}
}
if (gltfMat.pbrMetallicRoughness == null)
{
Debug.LogWarningFormat("Material #{0} has no PBR info.", gltfMat.gltfIndex);
return(null);
}
return(CreateNewPbrMaterial(baseMaterial, gltfMat.name, gltfMat.pbrMetallicRoughness));
}
/// <summary>
/// Converts the given GLTF 2 material to a Unity Material.
/// This is "best effort": we only interpret SOME, but not all GLTF material parameters.
/// We try to be robust, and will always try to return *some* material rather than fail,
/// even if crucial fields are missing or can't be parsed.
/// </summary>
/// <param name="gltfMat">The GLTF 2 material to convert.</param>
/// <returns>The result of the conversion</returns>
private UnityMaterial?ConvertGltf2Material(Gltf2Material gltfMat)
{
TbtSettings.PbrMaterialInfo pbrInfo;
string alphaMode = gltfMat.alphaMode == null ? null : gltfMat.alphaMode.ToUpperInvariant();
switch (alphaMode)
{
case null:
case "":
case Gltf2Material.kAlphaModeOpaque:
pbrInfo = gltfMat.doubleSided
? TbtSettings.Instance.m_PbrOpaqueDoubleSided
: TbtSettings.Instance.m_PbrOpaqueSingleSided;
break;
case Gltf2Material.kAlphaModeBlend:
pbrInfo = gltfMat.doubleSided
? TbtSettings.Instance.m_PbrBlendDoubleSided
: TbtSettings.Instance.m_PbrBlendSingleSided;
break;
default:
Debug.LogWarning($"Not yet supported: alphaMode={alphaMode}");
goto case Gltf2Material.kAlphaModeOpaque;
}
if (gltfMat.pbrMetallicRoughness == null)
{
var specGloss = gltfMat.extensions?.KHR_materials_pbrSpecularGlossiness;
if (specGloss != null)
{
// Try and make the best of pbrSpecularGlossiness.
// Maybe it would be better to support "extensionsRequired" and raise an error
// if the asset requires pbrSpecularGlossiness.
gltfMat.pbrMetallicRoughness = new Gltf2Material.PbrMetallicRoughness {
baseColorFactor = specGloss.diffuseFactor,
baseColorTexture = specGloss.diffuseTexture,
roughnessFactor = 1f - specGloss.glossinessFactor
};
}
else
{
Debug.LogWarningFormat("Material #{0} has no PBR info.", gltfMat.gltfIndex);
return(null);
}
}
return(CreateNewPbrMaterial(pbrInfo, gltfMat.name, gltfMat.pbrMetallicRoughness));
}
/// <summary>
/// Converts the given GLTF 2 material to a Unity Material.
/// This is "best effort": we only interpret SOME, but not all GLTF material parameters.
/// We try to be robust, and will always try to return *some* material rather than fail,
/// even if crucial fields are missing or can't be parsed.
/// </summary>
/// <param name="gltfMat">The GLTF 2 material to convert.</param>
/// <returns>The result of the conversion</returns>
private UnityMaterial?ConvertGltf2Material(Gltf2Material gltfMat)
{
TbtSettings.PbrMaterialInfo pbrInfo;
#if TILT_BRUSH
if (!gltfMat.doubleSided)
{
// TBT supports importing single-sided materials, forcing TB to try.
// TB will import them but can't export single-sided because it lacks single-sided BD.
// Single-sided BD
// TB's copy of TbtSettings uses our double-sided BrushDescriptor for these single-sided
// materials, so they'll export as double-sided.
// TODO: create single-sided BrushDescriptors, push out to TBT, PT, Poly, ...
Debug.LogWarning($"Not fully supported: single-sided");
}
#endif
string alphaMode = gltfMat.alphaMode == null ? null : gltfMat.alphaMode.ToUpperInvariant();
switch (alphaMode)
{
case null:
case "":
case Gltf2Material.kAlphaModeOpaque:
pbrInfo = gltfMat.doubleSided
? TbtSettings.Instance.m_PbrOpaqueDoubleSided
: TbtSettings.Instance.m_PbrOpaqueSingleSided;
break;
case Gltf2Material.kAlphaModeBlend:
pbrInfo = gltfMat.doubleSided
? TbtSettings.Instance.m_PbrBlendDoubleSided
: TbtSettings.Instance.m_PbrBlendSingleSided;
break;
default:
Debug.LogWarning($"Not yet supported: alphaMode={alphaMode}");
goto case Gltf2Material.kAlphaModeOpaque;
}
if (gltfMat.pbrMetallicRoughness == null)
{
var specGloss = gltfMat.extensions?.KHR_materials_pbrSpecularGlossiness;
if (specGloss != null)
{
// Try and make the best of pbrSpecularGlossiness.
// Maybe it would be better to support "extensionsRequired" and raise an error
// if the asset requires pbrSpecularGlossiness.
gltfMat.pbrMetallicRoughness = new Gltf2Material.PbrMetallicRoughness {
baseColorFactor = specGloss.diffuseFactor,
baseColorTexture = specGloss.diffuseTexture,
roughnessFactor = 1f - specGloss.glossinessFactor
};
}
else
{
Debug.LogWarningFormat("Material #{0} has no PBR info.", gltfMat.gltfIndex);
return(null);
}
}
return(CreateNewPbrMaterial(pbrInfo, gltfMat.name, gltfMat.pbrMetallicRoughness));
}
/// <summary>
/// Looks up a built-in global material that corresponds to the given GLTF material.
/// This will NOT create new materials; it will only look up global ones.
/// </summary>
/// <param name="gltfMaterial">The material to look up.</param>
/// <param name="materialGuid">The guid parsed from the material name, or Guid.None</param>
/// <returns>The global material that corresponds to the given GLTF material,
/// if found. If not found, null.</returns>
private static UnityMaterial?LookUpGlobalMaterial(GltfMaterialBase gltfMaterial)
{
#if TILT_BRUSH
// Is this a Gltf1 blocks material?
if (gltfMaterial.TechniqueExtras != null)
{
string surfaceShader = null;
gltfMaterial.TechniqueExtras.TryGetValue("gvrss", out surfaceShader);
if (surfaceShader != null)
{
// Blocks material. Look up the mapping in TbtSettings.
if (TbtSettings.Instance.LookupSurfaceShaderMaterial(surfaceShader) is UnityMaterial um)
{
return(um);
}
else
{
Debug.LogWarningFormat("Unknown gvrss surface shader {0}", surfaceShader);
}
}
}
// This method of building Guid from a name is flimsy, and proven so by b/109698832.
// As a patch fix, look specifically for Blocks material names.
// Is this a Gltf2 Blocks material?
Gltf2Material gltf2 = gltfMaterial as Gltf2Material;
if (gltf2 != null)
{
if (gltfMaterial.name != null)
{
string url = "https://vr.google.com/shaders/w/gvrss/";
if (gltfMaterial.name.Equals("BlocksGem"))
{
return(TbtSettings.Instance.LookupSurfaceShaderMaterial(url + "gem.json"));
}
if (gltfMaterial.name.Equals("BlocksGlass"))
{
return(TbtSettings.Instance.LookupSurfaceShaderMaterial(url + "glass.json"));
}
if (gltfMaterial.name.Equals("BlocksPaper"))
{
return(TbtSettings.Instance.LookupSurfaceShaderMaterial(url + "paper.json"));
}
}
}
#endif
// Check if it's a Tilt Brush material.
Guid guid = ParseGuidFromMaterial(gltfMaterial);
if (guid != Guid.Empty)
{
// Tilt Brush global material. PBR materials will use unrecognized guids;
// these will be handled by the caller.
BrushDescriptor desc;
if (TbtSettings.Instance.TryGetBrush(guid, out desc))
{
return(new UnityMaterial {
material = desc.Material,
#if TILT_BRUSH
exportableMaterial = desc,
#endif
template = desc.Material
});
}
}
return(null);
}
/// Map gltfIndex values (ie, int indices) names to the objects they refer to
public override void Dereference(IUriLoader uriLoader = null, PolyFormat gltfFormat = null)
{
// "dereference" all the indices
scenePtr = scenes[scene];
for (int i = 0; i < buffers.Count; i++)
{
Gltf2Buffer buffer = buffers[i];
buffer.gltfIndex = i;
if (uriLoader != null)
{
// Only id 0 may lack a URI; this indicates that it is the binary chunk.
Debug.Assert(!(i != 0 && buffer.uri == null));
buffer.data = uriLoader.Load(buffer.uri);
}
else if (gltfFormat != null)
{
// Runtime import case; the uris refer to resource files in the PolyFormat.
foreach (PolyFile resource in gltfFormat.resources)
{
if (resource.relativePath == buffer.uri)
{
buffer.data = new Reader(resource.contents);
break;
}
}
}
}
for (int i = 0; i < accessors.Count; i++)
{
accessors[i].gltfIndex = i;
accessors[i].bufferViewPtr = bufferViews[accessors[i].bufferView];
}
for (int i = 0; i < bufferViews.Count; i++)
{
bufferViews[i].gltfIndex = i;
bufferViews[i].bufferPtr = buffers[bufferViews[i].buffer];
}
for (int i = 0; i < meshes.Count; i++)
{
meshes[i].gltfIndex = i;
foreach (var prim in meshes[i].primitives)
{
prim.attributePtrs = prim.attributes.ToDictionary(
elt => elt.Key,
elt => accessors[elt.Value]);
prim.indicesPtr = accessors[prim.indices];
prim.materialPtr = materials[prim.material];
}
}
if (images != null)
{
for (int i = 0; i < images.Count; i++)
{
images[i].gltfIndex = i;
}
}
if (textures != null)
{
for (int i = 0; i < textures.Count; i++)
{
textures[i].gltfIndex = i;
textures[i].sourcePtr = images[textures[i].source];
}
}
for (int i = 0; i < materials.Count; i++)
{
Gltf2Material mat = materials[i];
mat.gltfIndex = i;
DereferenceTextureInfo(mat.emissiveTexture);
DereferenceTextureInfo(mat.normalTexture);
if (mat.pbrMetallicRoughness != null)
{
DereferenceTextureInfo(mat.pbrMetallicRoughness.baseColorTexture);
DereferenceTextureInfo(mat.pbrMetallicRoughness.metallicRoughnessTexture);
}
}
for (int i = 0; i < nodes.Count; i++)
{
nodes[i].gltfIndex = i;
Gltf2Node node = nodes[i];
if (node.mesh >= 0)
{
node.meshPtr = meshes[node.mesh];
}
if (node.children != null)
{
node.childPtrs = node.children.Select(id => nodes[id]).ToList();
}
}
for (int i = 0; i < scenes.Count; i++)
{
scenes[i].gltfIndex = i;
var thisScene = scenes[i];
if (thisScene.nodes != null)
{
thisScene.nodePtrs = thisScene.nodes.Select(index => nodes[index]).ToList();
}
}
}
/// Map gltfIndex values (ie, int indices) names to the objects they refer to
public override void Dereference(bool isGlb, IUriLoader uriLoader = null)
{
// "dereference" all the indices
scenePtr = scenes[scene];
for (int i = 0; i < buffers.Count; i++)
{
Gltf2Buffer buffer = buffers[i];
buffer.gltfIndex = i;
if (buffer.uri == null && !(i == 0 && isGlb))
{
Debug.LogErrorFormat("Buffer {0} isGlb {1} has null uri", i, isGlb);
// leave the data buffer null
return;
}
if (uriLoader != null)
{
buffer.data = uriLoader.Load(buffer.uri);
}
}
for (int i = 0; i < accessors.Count; i++)
{
accessors[i].gltfIndex = i;
accessors[i].bufferViewPtr = bufferViews[accessors[i].bufferView];
}
for (int i = 0; i < bufferViews.Count; i++)
{
bufferViews[i].gltfIndex = i;
bufferViews[i].bufferPtr = buffers[bufferViews[i].buffer];
}
for (int i = 0; i < meshes.Count; i++)
{
meshes[i].gltfIndex = i;
foreach (var prim in meshes[i].primitives)
{
prim.attributePtrs = prim.attributes.ToDictionary(
elt => elt.Key,
elt => accessors[elt.Value]);
prim.indicesPtr = accessors[prim.indices];
prim.materialPtr = materials[prim.material];
}
}
if (images != null)
{
for (int i = 0; i < images.Count; i++)
{
images[i].gltfIndex = i;
}
}
if (textures != null)
{
for (int i = 0; i < textures.Count; i++)
{
textures[i].gltfIndex = i;
textures[i].sourcePtr = images[textures[i].source];
}
}
for (int i = 0; i < materials.Count; i++)
{
Gltf2Material mat = materials[i];
mat.gltfIndex = i;
DereferenceTextureInfo(mat.emissiveTexture);
DereferenceTextureInfo(mat.normalTexture);
if (mat.pbrMetallicRoughness != null)
{
DereferenceTextureInfo(mat.pbrMetallicRoughness.baseColorTexture);
DereferenceTextureInfo(mat.pbrMetallicRoughness.metallicRoughnessTexture);
}
DereferenceTextureInfo(mat.extensions?.KHR_materials_pbrSpecularGlossiness?.diffuseTexture);
}
for (int i = 0; i < nodes.Count; i++)
{
nodes[i].gltfIndex = i;
Gltf2Node node = nodes[i];
if (node.mesh >= 0)
{
node.meshPtr = meshes[node.mesh];
}
if (node.children != null)
{
node.childPtrs = node.children.Select(id => nodes[id]).ToList();
}
}
for (int i = 0; i < scenes.Count; i++)
{
scenes[i].gltfIndex = i;
var thisScene = scenes[i];
if (thisScene.nodes != null)
{
thisScene.nodePtrs = thisScene.nodes.Select(index => nodes[index]).ToList();
}
}
}
