irrlicht/source/Irrlicht/CGLTFMeshFileLoader.h
2023-11-29 05:51:32 -05:00

140 lines
3.4 KiB
C++

#ifndef __C_GLTF_MESH_FILE_LOADER_INCLUDED__
#define __C_GLTF_MESH_FILE_LOADER_INCLUDED__
#include "IAnimatedMesh.h"
#include "IMeshLoader.h"
#include "IReadFile.h"
#include "irrTypes.h"
#include "path.h"
#include "S3DVertex.h"
#include "SMesh.h"
#include "vector2d.h"
#include "vector3d.h"
#include "tinygltf/tiny_gltf.h"
#include <cstddef>
#include <vector>
namespace irr
{
namespace scene
{
class CGLTFMeshFileLoader : public IMeshLoader
{
public:
CGLTFMeshFileLoader() noexcept;
bool isALoadableFileExtension(const io::path& filename) const override;
IAnimatedMesh* createMesh(io::IReadFile* file) override;
private:
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;
};
class MeshExtractor {
public:
using vertex_t = video::S3DVertex;
MeshExtractor(const tinygltf::Model& model) noexcept;
MeshExtractor(const tinygltf::Model&& model) noexcept;
/* Gets indices for the given mesh/primitive.
*
* Values are return in Irrlicht winding order.
*/
std::vector<u16> getIndices(const std::size_t meshIdx,
const std::size_t primitiveIdx) const;
std::vector<vertex_t> getVertices(std::size_t meshIdx,
const std::size_t primitiveIdx) const;
std::size_t getMeshCount() const;
std::size_t getPrimitiveCount(const std::size_t meshIdx) const;
private:
tinygltf::Model m_model;
template <typename T>
static T readPrimitive(const BufferOffset& readFrom);
static core::vector2df readVec2DF(
const BufferOffset& readFrom);
/* Read a vec3df from a buffer with transformations applied.
*
* Values are returned in Irrlicht coordinates.
*/
static core::vector3df readVec3DF(
const BufferOffset& readFrom,
const float scale = 1.0f);
void copyPositions(const std::size_t accessorIdx,
std::vector<vertex_t>& vertices) const;
void copyNormals(const std::size_t accessorIdx,
std::vector<vertex_t>& vertices) const;
void copyTCoords(const std::size_t accessorIdx,
std::vector<vertex_t>& vertices) const;
/* Get the scale factor from the glTF mesh information.
*
* Returns 1.0f if no scale factor is present.
*/
float getScale() const;
std::size_t getElemCount(const std::size_t accessorIdx) const;
BufferOffset getBuffer(const std::size_t accessorIdx) const;
std::size_t getIndicesAccessorIdx(const std::size_t meshIdx,
const std::size_t primitiveIdx) const;
std::size_t getPositionAccessorIdx(const std::size_t meshIdx,
const std::size_t primitiveIdx) const;
/* Get the accessor id of the normals of a primitive.
*
* -1 is returned if none are present.
*/
std::size_t getNormalAccessorIdx(const std::size_t meshIdx,
const std::size_t primitiveIdx) const;
/* Get the accessor id for the tcoords of a primitive.
*
* -1 is returned if none are present.
*/
std::size_t getTCoordAccessorIdx(const std::size_t meshIdx,
const std::size_t primitiveIdx) const;
};
void loadPrimitives(const MeshExtractor& parser, SMesh* mesh);
static bool tryParseGLTF(io::IReadFile* file,
tinygltf::Model& model);
};
} // namespace scene
} // namespace irr
#endif // __C_GLTF_MESH_FILE_LOADER_INCLUDED__