Implemented KHR_gaussian_splatting extension

Author: warrenm

cgltf.h

@@ -598,6 +598,16 @@ typedef struct cgltf_draco_mesh_compression {
 	cgltf_size attributes_count;
 } cgltf_draco_mesh_compression;
 
+typedef struct cgltf_gaussian_splatting {
+    char* kernel;
+    char* color_space;
+    char* sorting_method;
+    char* projection;
+    cgltf_extras extras;
+    cgltf_size extensions_count;
+    cgltf_extension* extensions;
+} cgltf_gaussian_splatting;
+
 typedef struct cgltf_mesh_gpu_instancing {
 	cgltf_attribute* attributes;
 	cgltf_size attributes_count;
@@ -616,6 +626,8 @@ typedef struct cgltf_primitive {
 	cgltf_draco_mesh_compression draco_mesh_compression;
 	cgltf_material_mapping* mappings;
 	cgltf_size mappings_count;
+	cgltf_bool has_gaussian_splatting;
+	cgltf_gaussian_splatting gaussian_splatting;
 	cgltf_size extensions_count;
 	cgltf_extension* extensions;
 } cgltf_primitive;
@@ -3139,6 +3151,55 @@ static int cgltf_parse_json_draco_mesh_compression(cgltf_options* options, jsmnt
 	return i;
 }
 
+static int cgltf_parse_json_gaussian_splatting(cgltf_options* options, jsmntok_t const* tokens, int i, const uint8_t* json_chunk, cgltf_gaussian_splatting* out_gaussian_splatting)
+{
+	CGLTF_CHECK_TOKTYPE(tokens[i], JSMN_OBJECT);
+
+	int size = tokens[i].size;
+	++i;
+
+	for (int j = 0; j < size; ++j)
+	{
+		CGLTF_CHECK_KEY(tokens[i]);
+
+		if (cgltf_json_strcmp(tokens + i, json_chunk, "kernel") == 0)
+		{
+			i = cgltf_parse_json_string(options, tokens, i + 1, json_chunk, &out_gaussian_splatting->kernel);
+		}
+		else if (cgltf_json_strcmp(tokens + i, json_chunk, "colorSpace") == 0)
+		{
+			i = cgltf_parse_json_string(options, tokens, i + 1, json_chunk, &out_gaussian_splatting->color_space);
+		}
+		else if (cgltf_json_strcmp(tokens + i, json_chunk, "sortingMethod") == 0)
+		{
+			i = cgltf_parse_json_string(options, tokens, i + 1, json_chunk, &out_gaussian_splatting->sorting_method);
+		}
+		else if (cgltf_json_strcmp(tokens + i, json_chunk, "projection") == 0)
+		{
+			i = cgltf_parse_json_string(options, tokens, i + 1, json_chunk, &out_gaussian_splatting->projection);
+		}
+		else if (cgltf_json_strcmp(tokens + i, json_chunk, "extras") == 0)
+		{
+			i = cgltf_parse_json_extras(options, tokens, i + 1, json_chunk, &out_gaussian_splatting->extras);
+		}
+		else if (cgltf_json_strcmp(tokens + i, json_chunk, "extensions") == 0)
+		{
+			i = cgltf_parse_json_unprocessed_extensions(options, tokens, i, json_chunk, &out_gaussian_splatting->extensions_count, &out_gaussian_splatting->extensions);
+		}
+		else
+		{
+			i = cgltf_skip_json(tokens, i+1);
+		}
+
+		if (i < 0)
+		{
+			return i;
+		}
+	}
+
+	return i;
+}
+
 static int cgltf_parse_json_mesh_gpu_instancing(cgltf_options* options, jsmntok_t const* tokens, int i, const uint8_t* json_chunk, cgltf_mesh_gpu_instancing* out_mesh_gpu_instancing)
 {
 	CGLTF_CHECK_TOKTYPE(tokens[i], JSMN_OBJECT);
@@ -3410,6 +3471,11 @@ static int cgltf_parse_json_primitive(cgltf_options* options, jsmntok_t const* t
 					out_prim->has_draco_mesh_compression = 1;
 					i = cgltf_parse_json_draco_mesh_compression(options, tokens, i + 1, json_chunk, &out_prim->draco_mesh_compression);
 				}
+				else if (cgltf_json_strcmp(tokens+i, json_chunk, "KHR_gaussian_splatting") == 0)
+				{
+					out_prim->has_gaussian_splatting = 1;
+					i = cgltf_parse_json_gaussian_splatting(options, tokens, i + 1, json_chunk, &out_prim->gaussian_splatting);
+				}
 				else if (cgltf_json_strcmp(tokens+i, json_chunk, "KHR_materials_variants") == 0)
 				{
 					i = cgltf_parse_json_material_mappings(options, tokens, i + 1, json_chunk, out_prim);

cgltf_write.h

@@ -89,6 +89,7 @@ cgltf_size cgltf_write(const cgltf_options* options, char* buffer, cgltf_size si
 #define CGLTF_EXTENSION_FLAG_MATERIALS_DISPERSION (1 << 17)
 #define CGLTF_EXTENSION_FLAG_TEXTURE_WEBP          (1 << 18)
 #define CGLTF_EXTENSION_FLAG_MATERIALS_DIFFUSE_TRANSMISSION (1 << 19)
+#define CGLTF_EXTENSION_FLAG_GAUSSIAN_SPLATTING     (1 << 20)
 
 typedef struct {
 	char* buffer;
@@ -523,6 +524,18 @@ static void cgltf_write_primitive(cgltf_write_context* context, const cgltf_prim
 			cgltf_write_line(context, "}");
 		}
 
+		if (prim->has_gaussian_splatting)
+		{
+			context->extension_flags |= CGLTF_EXTENSION_FLAG_GAUSSIAN_SPLATTING;
+			cgltf_write_line(context, "\"KHR_gaussian_splatting\": {");
+			cgltf_write_strprop(context, "kernel", prim->gaussian_splatting.kernel);
+			cgltf_write_strprop(context, "colorSpace", prim->gaussian_splatting.color_space);
+			cgltf_write_strprop(context, "sortingMethod", prim->gaussian_splatting.sorting_method);
+			cgltf_write_strprop(context, "projection", prim->gaussian_splatting.projection);
+			cgltf_write_extras(context, &prim->gaussian_splatting.extras);
+			cgltf_write_line(context, "}");
+		}
+		
 		if (prim->mappings_count > 0)
 		{
 			context->extension_flags |= CGLTF_EXTENSION_FLAG_MATERIALS_VARIANTS;
@@ -1329,6 +1342,9 @@ static void cgltf_write_extensions(cgltf_write_context* context, uint32_t extens
 	if (extension_flags & CGLTF_EXTENSION_FLAG_MATERIALS_DISPERSION) {
 		cgltf_write_stritem(context, "KHR_materials_dispersion");
 	}
+	if (extension_flags & CGLTF_EXTENSION_FLAG_GAUSSIAN_SPLATTING) {
+		cgltf_write_stritem(context, "KHR_gaussian_splatting");
+	}
 }
 
 cgltf_size cgltf_write(const cgltf_options* options, char* buffer, cgltf_size size, const cgltf_data* data)