Reorganize CGLTFMeshFileLoader help functions

I moved them all into static methods and changed the ordering in the
source file so that createMesh() would be close to the top of the file.
I also corrected formatting in some of the function declarations since I
had to change them anyway.

source/Irrlicht/CGLTFMeshFileLoader.h

@@ -1,4 +1,3 @@
-<<<<<<< HEAD
 #ifndef __C_GLTF_MESH_FILE_LOADER_INCLUDED__
 #define __C_GLTF_MESH_FILE_LOADER_INCLUDED__
 
@@ -6,6 +5,14 @@
 #include "IMeshLoader.h"
 #include "IReadFile.h"
 #include "path.h"
+#include "S3DVertex.h"
+#include "vector2d.h"
+#include "vector3d.h"
+
+#include <tiny_gltf.h>
+
+#include <cstddef>
+#include <vector>
 
 namespace irr
 {
@@ -16,14 +23,72 @@ namespace scene
 class CGLTFMeshFileLoader : public IMeshLoader
 {
 public:
-	CGLTFMeshFileLoader();
+	CGLTFMeshFileLoader() noexcept;
 
 	bool isALoadableFileExtension(const io::path& filename) const override;
 
 	IAnimatedMesh* createMesh(io::IReadFile* file) override;
 
 private:
-	bool tryParseGLTF(io::IReadFile* file) const;
+	template <typename T>
+	struct Span
+	{
+		T* buffer = nullptr;
+		std::size_t size = 0;
+	};
+
+	class BufferOffset
+	{
+	public:
+		BufferOffset(const std::vector<unsigned char>& buf,
+				const std::size_t offset);
+
+		BufferOffset(const BufferOffset& other,
+				const std::size_t fromOffset);
+
+		unsigned char at(const std::size_t fromOffset) const;
+	private:
+		const std::vector<unsigned char>& m_buf;
+		std::size_t m_offset;
+		int m_filesize;
+	};
+
+	template <typename T>
+	static T readPrimitive(const BufferOffset& readFrom);
+
+	static core::vector2df readVec2DF(
+			const BufferOffset& readFrom);
+
+	static core::vector3df readVec3DF(
+			const BufferOffset& readFrom,
+			const float scale);
+
+	static void copyPositions(const tinygltf::Model& model,
+			const Span<video::S3DVertex> vertices,
+			const std::size_t accessorId);
+
+	static void copyNormals(const tinygltf::Model& model,
+			const Span<video::S3DVertex> vertices,
+			const std::size_t accessorId);
+
+	static void copyTCoords(const tinygltf::Model& model,
+			const Span<video::S3DVertex> vertices,
+			const std::size_t accessorId);
+
+	static void getIndices(const tinygltf::Model& model,
+			const std::size_t accessorId,
+			std::vector<u16>& indicesBuffer);
+
+	static void getVertices(const tinygltf::Model& model,
+			const std::size_t accessorId,
+			Span<video::S3DVertex>& outVertices,
+			std::size_t meshIndex,
+			std::size_t primitiveIndex);
+
+	static bool tryParseGLTF(io::IReadFile* file,
+			tinygltf::Model& model);
+
+	static float getScale(const tinygltf::Model& model);
 };
 
 } // namespace scene
@@ -31,3 +96,4 @@ private:
 } // namespace irr
 
 #endif // __C_GLTF_MESH_FILE_LOADER_INCLUDED__
+