shader.h

#ifndef _SHADER_H
#define _SHADER_H

#include <GLFW/glfw3.h>

#include "math4.h"
#include "log.h"

#define shader_debug(...) debugf("Shader", __VA_ARGS__)
#define shader_error(...) errorf("Shader", __VA_ARGS__)

#define SHADER_OK					 0
#define SHADER_COMPILE_ERROR		-1
#define SHADER_LINK_ERROR			-2
#define SHADER_OOM_ERROR			-3
#define SHADER_UNIFORMS_MAX_ERROR	-4

#define UNIFORM_NAME_TRANSFORM		"transform"
#define UNIFORM_NAME_PROJECTION		"projection"
#define UNIFORM_NAME_COLOR			"color"
#define UNIFORM_NAME_SPRITE_TYPE	"sprite_type"
#define UNIFORM_NAME_TEX			"tex"

#define ATTRIB_NAME_POSITION		"vp"
#define ATTRIB_NAME_TEXCOORD		"texcoord_in"

#define TYPE_VEC_1F	                0
#define TYPE_VEC_2F	                1
#define TYPE_VEC_3F	                2
#define TYPE_VEC_4F	                3
//#define TYPE_MAT_2F	            4
//#define TYPE_MAT_3F               5
#define TYPE_MAT_4F	                6

#define UNIFORMS_MAX                64

struct uniform {
    const char  *name;
    GLint       id;
    int         datatype;
    void        *data;
};

struct shader {
	const char	    *vert_src;
	int			    vert_src_len;
	const char	    *frag_src;
	int			    frag_src_len;
	GLuint		    program;
	GLint		    uniform_transform;
	GLint		    uniform_projection;
	GLint		    uniform_color;
	GLint		    uniform_sprite_type;
	GLint		    uniform_tex;
	struct uniform	*uniforms[UNIFORMS_MAX];
};

int     shader_init(struct shader *s,
				char *vert_src, int vert_src_len,
                char *frag_src, int frag_src_len);
void    shader_delete(struct shader *s);
void    shader_free(struct shader *s);

int		shader_uniform(struct shader *s, const char *name, void *data, int type);
int		shader_uniform1f(struct shader *s, const char *name, float *data);
int		shader_uniform2f(struct shader *s, const char *name, vec2 *data);
int		shader_uniform3f(struct shader *s, const char *name, vec3 *data);
int		shader_uniform4f(struct shader *s, const char *name, vec4 *data);
int		shader_uniform_matrix4f(struct shader *s, const char *name, mat4 *data);

void	shader_uniforms_relocate(struct shader *s);
void	shader_uniforms_free(struct shader *s);
void    shader_uniforms_think(struct shader *s, float delta_time);

#endif