KHR_materials_unlit (#61)

KHR_materials_unlit support.

.gitignore

@@ -0,0 +1 @@
+build/

src/Raw2Gltf.cpp

@@ -852,6 +852,9 @@ ModelData *Raw2Gltf(
                         diffuseTex.get(), diffuseFactor, specGlossTex.get(), specularFactor, glossiness));
             }
 
+            TextureData *normalTexture = simpleTex(RAW_TEXTURE_USAGE_NORMAL).get();
+            TextureData *emissiveTexture = simpleTex(RAW_TEXTURE_USAGE_EMISSIVE).get();
+
             std::shared_ptr<KHRCommonMats> khrComMat;
             if (options.useKHRMatCom) {
                 float                        shininess;
@@ -905,12 +908,38 @@ ModelData *Raw2Gltf(
                         diffuseTex.get(), diffuseFactor,
                         simpleTex(RAW_TEXTURE_USAGE_SPECULAR).get(), specularFactor));
             }
+
+            std::shared_ptr<KHRCmnConstantMaterial> khrCmnConstantMat;
+            if (options.useKHRMatCmnConstant) {
+                normalTexture = nullptr;
+
+                emissiveTexture = nullptr;
+                emissiveFactor = Vec3f(0.00f, 0.00f, 0.00f);
+
+                Vec4f diffuseFactor;
+                std::shared_ptr<TextureData> baseColorTex;
+
+                if (material.info->shadingModel == RAW_SHADING_MODEL_PBR_MET_ROUGH) {
+                    RawMetRoughMatProps *props = (RawMetRoughMatProps *) material.info.get();
+                    diffuseFactor = props->diffuseFactor;
+                    baseColorTex = simpleTex(RAW_TEXTURE_USAGE_ALBEDO);
+                } else {
+                    RawTraditionalMatProps *props = ((RawTraditionalMatProps *) material.info.get());
+                    diffuseFactor = props->diffuseFactor;
+                    baseColorTex = simpleTex(RAW_TEXTURE_USAGE_DIFFUSE);
+                }
+
+                pbrMetRough.reset(new PBRMetallicRoughness(baseColorTex.get(), nullptr, diffuseFactor, 0.0f, 1.0f));
+
+                khrCmnConstantMat.reset(new KHRCmnConstantMaterial());
+            }
+
             std::shared_ptr<MaterialData> mData = gltf->materials.hold(
                 new MaterialData(
                     material.name, isTransparent,
-                    simpleTex(RAW_TEXTURE_USAGE_NORMAL).get(), simpleTex(RAW_TEXTURE_USAGE_EMISSIVE).get(),
+                    normalTexture, emissiveTexture,
                     emissiveFactor * emissiveIntensity,
-                    khrComMat, pbrMetRough, pbrSpecGloss));
+                    khrComMat, khrCmnConstantMat, pbrMetRough, pbrSpecGloss));
             materialsByName[materialHash(material)] = mData;
         }
 
@@ -1188,6 +1217,9 @@ ModelData *Raw2Gltf(
                 extensionsRequired.push_back(KHR_MATERIALS_COMMON);
             }
         }
+        if (options.useKHRMatCmnConstant) {
+            extensionsUsed.push_back(KHR_MATERIALS_CMN_CONSTANT);
+        }
         if (options.usePBRSpecGloss) {
             extensionsUsed.push_back(KHR_MATERIALS_PBR_SPECULAR_GLOSSINESS);
             if (!options.useKHRMatCom && !options.usePBRMetRough) {

src/Raw2Gltf.h

@@ -30,6 +30,7 @@ using json = nlohmann::basic_json<workaround_fifo_map>;
 
 static const std::string KHR_DRACO_MESH_COMPRESSION            = "KHR_draco_mesh_compression";
 static const std::string KHR_MATERIALS_COMMON                  = "KHR_materials_common";
+static const std::string KHR_MATERIALS_CMN_CONSTANT                  = "KHR_materials_unlit";
 static const std::string KHR_MATERIALS_PBR_SPECULAR_GLOSSINESS = "KHR_materials_pbrSpecularGlossiness";
 
 static const std::string extBufferFilename = "buffer.bin";
@@ -54,6 +55,8 @@ struct GltfOptions
     bool useDraco;
     /** Whether to use KHR_materials_common to extend materials definitions. */
     bool useKHRMatCom;
+    /** Whether to use KHR_materials_cmnConstant to extend materials definitions. */
+    bool useKHRMatCmnConstant;
     /** Whether to populate the pbrMetallicRoughness substruct in materials. */
     bool usePBRMetRough;
     /** Whether to use KHR_materials_pbrSpecularGlossiness to extend material definitions. */

src/glTF/MaterialData.cpp

@@ -93,6 +93,15 @@ void to_json(json &j, const KHRCommonMats &d)
     }
 }
 
+KHRCmnConstantMaterial::KHRCmnConstantMaterial()
+{
+}
+
+void to_json(json &j, const KHRCmnConstantMaterial &d)
+{
+	j = json({});
+}
+
 PBRSpecularGlossiness::PBRSpecularGlossiness(
     const TextureData *diffuseTexture, const Vec4f &diffuseFactor,
     const TextureData *specularGlossinessTexture, const Vec3f &specularFactor,
@@ -161,6 +170,7 @@ MaterialData::MaterialData(
     std::string name,  bool isTransparent, const TextureData *normalTexture,
     const TextureData *emissiveTexture, const Vec3f & emissiveFactor,
     std::shared_ptr<KHRCommonMats> const khrCommonMats,
+    std::shared_ptr<KHRCmnConstantMaterial> const khrCmnConstantMaterial,
     std::shared_ptr<PBRMetallicRoughness> const pbrMetallicRoughness,
     std::shared_ptr<PBRSpecularGlossiness> const pbrSpecularGlossiness)
     : Holdable(),
@@ -170,6 +180,7 @@ MaterialData::MaterialData(
       emissiveTexture(Tex::ref(emissiveTexture)),
       emissiveFactor(std::move(emissiveFactor)),
       khrCommonMats(khrCommonMats),
+      khrCmnConstantMaterial(khrCmnConstantMaterial),
       pbrMetallicRoughness(pbrMetallicRoughness),
       pbrSpecularGlossiness(pbrSpecularGlossiness) {}
 
@@ -192,11 +203,14 @@ json MaterialData::serialize() const
     if (pbrMetallicRoughness != nullptr) {
         result["pbrMetallicRoughness"] = *pbrMetallicRoughness;
     }
-    if (khrCommonMats != nullptr || pbrSpecularGlossiness != nullptr) {
+    if (khrCommonMats != nullptr || khrCmnConstantMaterial != nullptr || pbrSpecularGlossiness != nullptr) {
         json extensions = { };
         if (khrCommonMats != nullptr) {
             extensions[KHR_MATERIALS_COMMON] = *khrCommonMats;
         }
+        if (khrCmnConstantMaterial != nullptr) {
+            extensions[KHR_MATERIALS_CMN_CONSTANT] = *khrCmnConstantMaterial;
+        }
         if (pbrSpecularGlossiness != nullptr) {
             extensions[KHR_MATERIALS_PBR_SPECULAR_GLOSSINESS] = *pbrSpecularGlossiness;
         }

src/glTF/MaterialData.h

@@ -53,6 +53,11 @@ struct KHRCommonMats
     const Vec3f                specularFactor;
 };
 
+struct KHRCmnConstantMaterial
+{
+    KHRCmnConstantMaterial();
+};
+
 struct PBRSpecularGlossiness
 {
     PBRSpecularGlossiness(
@@ -86,6 +91,7 @@ struct MaterialData : Holdable
         std::string name, bool isTransparent, const TextureData *normalTexture,
         const TextureData *emissiveTexture, const Vec3f &emissiveFactor,
         std::shared_ptr<KHRCommonMats> const khrCommonMats,
+        std::shared_ptr<KHRCmnConstantMaterial> const khrCmnConstantMaterial,
         std::shared_ptr<PBRMetallicRoughness> const pbrMetallicRoughness,
         std::shared_ptr<PBRSpecularGlossiness> const pbrSpecularGlossiness);
 
@@ -97,13 +103,15 @@ struct MaterialData : Holdable
     const std::unique_ptr<const Tex> emissiveTexture;
     const Vec3f                      emissiveFactor;
 
-    const std::shared_ptr<const KHRCommonMats>         khrCommonMats;
+    const std::shared_ptr<const KHRCommonMats>          khrCommonMats;
-    const std::shared_ptr<const PBRMetallicRoughness>  pbrMetallicRoughness;
+    const std::shared_ptr<const KHRCmnConstantMaterial> khrCmnConstantMaterial;
-    const std::shared_ptr<const PBRSpecularGlossiness> pbrSpecularGlossiness;
+    const std::shared_ptr<const PBRMetallicRoughness>   pbrMetallicRoughness;
+    const std::shared_ptr<const PBRSpecularGlossiness>  pbrSpecularGlossiness;
 };
 
 void to_json(json &j, const Tex &data);
 void to_json(json &j, const KHRCommonMats &d);
+void to_json(json &j, const KHRCmnConstantMaterial &d);
 void to_json(json &j, const PBRSpecularGlossiness &d);
 void to_json(json &j, const PBRMetallicRoughness &d);
 

src/main.cpp

@@ -48,6 +48,7 @@ int main(int argc, char *argv[])
         false,         // embedResources
         false,         // useDraco
         false,         // useKHRMatCom
+        false,         // useKHRMatCmnConstant
         false,         // usePBRMetRough
         false,         // usePBRSpecGloss
         false,         // useBlendShapeNormals
@@ -77,6 +78,9 @@ int main(int argc, char *argv[])
                (
                    "khr-materials-common", "(WIP) Use KHR_materials_common extensions to specify Unlit/Lambert/Blinn/Phong shaders.",
                    cxxopts::value<bool>(gltfOptions.useKHRMatCom))
+               (
+                   "khr-materials-cmnConstant", "(WIP) Use KHR_materials_cmnConstant extension to specify Unlit shader.",
+                   cxxopts::value<bool>(gltfOptions.useKHRMatCmnConstant))
                (
                    "pbr-metallic-roughness", "(WIP) Try to glean glTF 2.0 native PBR attributes from the FBX.",
                    cxxopts::value<bool>(gltfOptions.usePBRMetRough))
@@ -129,7 +133,7 @@ Copyright (c) 2016-2017 Oculus VR, LLC.
         verboseOutput = true;
     }
 
-    if (!gltfOptions.useKHRMatCom && !gltfOptions.usePBRSpecGloss && !gltfOptions.usePBRMetRough) {
+    if (!gltfOptions.useKHRMatCmnConstant && !gltfOptions.useKHRMatCom && !gltfOptions.usePBRSpecGloss && !gltfOptions.usePBRMetRough) {
         if (verboseOutput) {
             fmt::printf("Defaulting to --pbr-metallic-roughness material support.\n");
         }