objzero.h

/*
https://github.com/jpcy/objzero

MIT License

Copyright (c) 2018-2019 Jonathan Young

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/
#ifndef OBJZERO_H
#define OBJZERO_H

#include <inttypes.h>

#ifdef __cplusplus
extern "C" {
#endif

typedef void *(*objzReallocFunc)(void *_ptr, size_t _size);
void objz_setRealloc(objzReallocFunc _realloc);

typedef void (*objzProgressFunc)(const char *_filename, int _percent);
void objz_setProgress(objzProgressFunc _progress);

#define OBJZ_INDEX_FORMAT_AUTO 0
#define OBJZ_INDEX_FORMAT_U32  1

// OBJZ_INDEX_FORMAT_AUTO: objzModel indices are uint32_t if any index > UINT16_MAX, otherwise they are uint16_t.
// OBJZ_INDEX_FORMAT_U32: objzModel indices are always uint32_t.
// Default is OBJZ_INDEX_FORMAT_AUTO.
void objz_setIndexFormat(uint32_t _format);

/*
Default vertex data structure looks like this:

typedef struct {
float pos[3];
float texcoord[2];
float normal[3];
} Vertex;

Which is equivalent to:

objz_setVertexFormat(sizeof(Vertex), offsetof(Vertex, pos), offsetof(Vertex, texcoord), offsetof(Vertex, normal));

texcoordOffset - optional: set to SIZE_MAX to ignore
normalOffset - optional: set to SIZE_MAX to ignore
*/
void objz_setVertexFormat(size_t _stride, size_t _positionOffset, size_t _texcoordOffset, size_t _normalOffset);

#define OBJZ_NAME_MAX 64

typedef struct {
	char name[OBJZ_NAME_MAX];
	float ambient[3]; // Ka
	float diffuse[3]; // Kd
	float emission[3]; // Ke
	float specular[3]; // Ks
	float specularExponent; // Ns
	float opacity; // d
	char ambientTexture[OBJZ_NAME_MAX]; // map_Ka
	char bumpTexture[OBJZ_NAME_MAX]; // map_Bump
	char diffuseTexture[OBJZ_NAME_MAX]; // map_Kd
	char emissionTexture[OBJZ_NAME_MAX]; // map_Ke
	char specularTexture[OBJZ_NAME_MAX]; // map_Ks
	char specularExponentTexture[OBJZ_NAME_MAX]; // map_Ns
	char opacityTexture[OBJZ_NAME_MAX];  // map_d
} objzMaterial;

typedef struct
{
	int32_t materialIndex; // -1 if no material
	uint32_t firstIndex;
	uint32_t numIndices;
} objzMesh;

typedef struct {
	char name[OBJZ_NAME_MAX];
	uint32_t firstMesh;
	uint32_t numMeshes;

	// If you want per-object vertices and indices, use these and subtract firstVertex from all the objzModel indices in firstIndex to firstIndex + numIndices - 1 range.
	uint32_t firstIndex;
	uint32_t numIndices;
	uint32_t firstVertex;
	uint32_t numVertices;
} objzObject;

#define OBJZ_FLAG_TEXCOORDS (1<<0)
#define OBJZ_FLAG_NORMALS   (1<<1)
#define OBJZ_FLAG_INDEX32   (1<<2)

typedef struct {
	uint32_t flags;
	
	// uint32_t if OBJZ_FLAG_INDEX32 flag is set, otherwise uint16_t.
	// See: objz_setIndexFormat
	void *indices;

	uint32_t numIndices;
	objzMaterial *materials;
	uint32_t numMaterials;
	objzMesh *meshes;
	uint32_t numMeshes;
	objzObject *objects;
	uint32_t numObjects;
	void *vertices; // See: objz_setVertexFormat
	uint32_t numVertices;
} objzModel;

objzModel *objz_load(const char *_filename);
void objz_destroy(objzModel *_model);
const char *objz_getError(); // Includes warnings.

#ifdef __cplusplus
} // extern "C"
#endif

#endif // OBJZERO_H