Use flatbuffers for model meta data

- Add flatbuffers dependency.
- Update codes using meta data.

Author: bluekyu

CMakeLists.txt

@@ -51,9 +51,39 @@ find_package(FreeType REQUIRED)
 if(FREETYPE_FOUND)
     message(STATUS "freetype include path: ${FREETYPE_INCLUDE_DIRS}")
 endif()
+
+# find flatbuffers
+if(NOT TARGET flatbuffers)
+    find_package(flatbuffers REQUIRED)
+endif()
+# ==================================================================================================
+
+# ==================================================================================================
+function(render_pipeline_generate_schema_headers)
+    # generate schema headers
+    if(NOT FlatBuffers_flatc)
+        message(FATAL_ERROR "Cannot find flatc program.")
+    endif()
+
+    file(GLOB flatc_input_files "${PROJECT_SOURCE_DIR}/resources/data/schema/*.fbs")
+    foreach(input_file ${flatc_input_files})
+        execute_process(
+            COMMAND ${FlatBuffers_flatc} -c --scoped-enums "${input_file}"
+            WORKING_DIRECTORY "${PROJECT_BINARY_DIR}/rpcore/schema"
+            RESULT_VARIABLE flatc_result
+        )
+        if(NOT (${flatc_result} EQUAL "0"))
+            message(SEND_ERROR "flatc returns error for a file '${input_file}'")
+        endif()
+    endforeach()
+
+    message(STATUS "Render Pipeline: Schema header files are generated.")
+endfunction()
 # ==================================================================================================
 
 # === target =======================================================================================
+render_pipeline_generate_schema_headers()
+
 include("${PROJECT_SOURCE_DIR}/files.cmake")
 add_library(${PROJECT_NAME} SHARED ${render_pipeline_sources} ${render_pipeline_headers})
 
@@ -85,7 +115,7 @@ target_link_libraries(${PROJECT_NAME}
 
     PRIVATE $<$<NOT:$<BOOL:${Boost_USE_STATIC_LIBS}>>:Boost::dynamic_linking>
     Boost::filesystem
-    ${FREETYPE_LIBRARIES} yaml-cpp spdlog::spdlog
+    ${FREETYPE_LIBRARIES} yaml-cpp spdlog::spdlog flatbuffers
 )
 
 set_target_properties(${PROJECT_NAME} PROPERTIES

cmake/FindFlatBuffers.cmake

@@ -0,0 +1,68 @@
+#.rst:
+# FindFlatBuffers
+# --------------
+#
+# FindFlatBuffers.cmake
+#
+# Author: Younguk Kim (bluekyu)
+# Date  : 2017-07-07
+#
+# Result Variables
+# ^^^^^^^^^^^^^^^^
+#
+# This module defines the following variables::
+#
+#   FlatBuffers_FOUND            - True if FlatBuffers has been found and can be used
+#
+# and the following imported targets::
+#
+#   flatbuffers        - FlatBuffers library
+
+cmake_minimum_required(VERSION 3.6)
+
+find_path(FlatBuffers_INCLUDE_DIR
+    NAMES "flatbuffers/flatbuffers.h"
+    PATHS "${FlatBuffers_ROOT}"
+    PATH_SUFFIXES include
+)
+
+find_library(FlatBuffers_LIBRARY
+    NAMES flatbuffers
+    PATHS "${FlatBuffers_ROOT}"
+    PATH_SUFFIXES lib
+)
+
+find_program(FlatBuffers_flatc
+    flatc
+    PATHS "${FlatBuffers_ROOT}/bin"
+)
+
+# Set FlatBuffers_FOUND
+include(FindPackageHandleStandardArgs)
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(FlatBuffers
+    FOUND_VAR FlatBuffers_FOUND
+    REQUIRED_VARS FlatBuffers_LIBRARY FlatBuffers_INCLUDE_DIR
+)
+
+if(FlatBuffers_FOUND)
+    message(STATUS "Found the FlatBuffers library")
+
+    if(NOT TARGET flatbuffers)
+        add_library(flatbuffers UNKNOWN IMPORTED)
+        set_target_properties(flatbuffers PROPERTIES
+            INTERFACE_INCLUDE_DIRECTORIES "${FlatBuffers_INCLUDE_DIR}"
+            IMPORTED_LOCATION "${FlatBuffers_LIBRARY}"
+            IMPORTED_LINK_INTERFACE_LANGUAGES "CXX"
+        )
+
+        # Make variables changeable to the advanced user
+        mark_as_advanced(FlatBuffers_LIBRARY)
+    endif()
+
+    if(FlatBuffers_flatc)
+        mark_as_advanced(FlatBuffers_flatc)
+    endif()
+
+    # Make variables changeable to the advanced user
+    mark_as_advanced(FlatBuffers_INCLUDE_DIR)
+endif()

render_pipeline/rpcore/util/rpmaterial.hpp

@@ -10,7 +10,7 @@ namespace rpcore {
 class RPMaterial
 {
 public:
-    enum class ShadingModel: int
+    enum class ShadingModel: int8_t
     {
         DEFAULT_MODEL = 0,
         EMISSIVE_MODEL,

render_pipeline/rpcore/util/rpmodel.hpp

@@ -19,8 +19,8 @@ class RENDER_PIPELINE_DECL RPModel
     RPModel(void) = default;
     RPModel(NodePath nodepath);
 
-    void load_meta_file(const std::string& file_path="");
-    void load_meta_data(const YAML::Node& yaml_node);
+    void load_meta_file(const Filename& file_path="");
+    void load_meta_data(const std::string& json_string);
 
 private:
     // function only PImpl

resources/data/schema/geom_node_schema.fbs

@@ -0,0 +1,11 @@
+include "rpmaterial_schema.fbs";
+
+namespace rpcore;
+
+table GeomNodeSchema {
+    geoms:[GeomSchema];
+}
+
+table GeomSchema {
+    material:RPMaterialSchema;
+}

resources/data/schema/luse_schema.fbs

@@ -0,0 +1,9 @@
+namespace rpcore;
+
+struct LVecBase4Schema
+{
+    x:float;
+    y:float;
+    z:float;
+    w:float;
+}

resources/data/schema/model_root_schema.fbs

@@ -0,0 +1,9 @@
+include "panda_node_schema.fbs";
+
+namespace rpcore;
+
+table ModelRootSchema {
+    root_node:PandaNodeSchema;
+}
+
+root_type ModelRootSchema;

resources/data/schema/panda_node_schema.fbs

@@ -0,0 +1,20 @@
+include "geom_node_schema.fbs";
+
+namespace rpcore;
+
+enum NodeTypeSchema : ubyte {
+    PandaNode,
+    GeomNode,
+}
+
+table PandaNodeSchema {
+    node_type:NodeTypeSchema;
+
+    name:string;
+    material:RPMaterialSchema;
+
+    children:[PandaNodeSchema];
+
+    // sub-class
+    geom_node:GeomNodeSchema;
+}

resources/data/schema/rpmaterial_schema.fbs

@@ -0,0 +1,23 @@
+include "luse_schema.fbs";
+
+namespace rpcore;
+
+enum ShadingModelSchema: byte {
+    None=-1,
+    Default=0,
+    Emissive,
+    Clearcoat,
+    Transparent,
+    Skin,
+    Foliage,
+}
+
+table RPMaterialSchema {
+    base_color:LVecBase4Schema;
+    specular_ior:float;
+    metallic:float;
+    roughness:float;
+    shading_model:ShadingModelSchema = None;
+    normal_factor:float;
+    arbitrary0:float;
+}

src/rpcore/util/rpgeomnode.cpp

@@ -37,10 +37,7 @@ RPMaterial RPGeomNode::get_material(int geom_index) const
     const RenderState* state = geom_node->get_geom_state(geom_index);
 
     if (!state->has_attrib(MaterialAttrib::get_class_type()))
-    {
-        RPObject::global_warn("RPGeomNode", fmt::format("Geom {} has no material!", geom_node->get_name()));
         return RPMaterial(nullptr);
-    }
 
     return RPMaterial(DCAST(MaterialAttrib, state->get_attrib(MaterialAttrib::get_class_type()))->get_material());
 }