Merge branch 'master' into blender2.8

intern/cycles/render/shader.cpp

@@ -700,4 +700,20 @@ float ShaderManager::linear_rgb_to_gray(float3 c)
 	return dot(c, rgb_to_y);
 }
 
+string ShaderManager::get_cryptomatte_materials(Scene *scene)
+{
+	string manifest = "{";
+	unordered_set<ustring, ustringHash> materials;
+	foreach(Shader *shader, scene->shaders) {
+		if(materials.count(shader->name)) {
+			continue;
+		}
+		materials.insert(shader->name);
+		uint32_t cryptomatte_id = util_murmur_hash3(shader->name.c_str(), shader->name.length(), 0);
+		manifest += string_printf("\"%s\":\"%08x\",", shader->name.c_str(), cryptomatte_id);
+	}
+	manifest[manifest.size()-1] = '}';
+	return manifest;
+}
+
 CCL_NAMESPACE_END