nuclear@14: #include "imago2.h"
nuclear@14: 
nuclear@14: /* to avoid dependency to OpenGL, I'll define all the relevant GL macros manually */
nuclear@14: #define GL_UNSIGNED_BYTE		0x1401
nuclear@14: #define GL_FLOAT				0x1406
nuclear@14: 
nuclear@14: #define GL_LUMINANCE			0x1909
nuclear@14: #define GL_RGB					0x1907
nuclear@14: #define GL_RGBA					0x1908
nuclear@14: 
nuclear@14: #define GL_RGBA32F				0x8814
nuclear@14: #define GL_RGB32F				0x8815
nuclear@14: #define GL_LUMINANCE32F			0x8818
nuclear@14: 
nuclear@14: #define GL_TEXTURE_2D			0x0de1
nuclear@14: #define GL_TEXTURE_WRAP_S		0x2802
nuclear@14: #define GL_TEXTURE_WRAP_T		0x2803
nuclear@14: #define GL_TEXTURE_MAG_FILTER	0x2800
nuclear@14: #define GL_TEXTURE_MIN_FILTER	0x2801
nuclear@14: #define GL_LINEAR				0x2601
nuclear@14: #define GL_REPEAT				0x2901
nuclear@14: 
nuclear@14: 
nuclear@14: typedef unsigned int GLenum;
nuclear@14: typedef unsigned int GLuint;
nuclear@14: typedef int GLint;
nuclear@14: typedef int GLsizei;
nuclear@14: typedef void GLvoid;
nuclear@14: 
nuclear@14: /* for the same reason I'll load GL functions dynamically */
nuclear@14: #ifndef WIN32
nuclear@14: typedef void (*gl_gen_textures_func)(GLsizei, GLuint*);
nuclear@14: typedef void (*gl_bind_texture_func)(GLenum, GLuint);
nuclear@14: typedef void (*gl_tex_parameteri_func)(GLenum, GLenum, GLint);
nuclear@14: typedef void (*gl_tex_image2d_func)(GLenum, GLint, GLint, GLsizei, GLsizei, GLint, GLenum, GLenum, const GLvoid*);
nuclear@14: #else
nuclear@14: typedef void (__stdcall *gl_gen_textures_func)(GLsizei, GLuint*);
nuclear@14: typedef void (__stdcall *gl_bind_texture_func)(GLenum, GLuint);
nuclear@14: typedef void (__stdcall *gl_tex_parameteri_func)(GLenum, GLenum, GLint);
nuclear@14: typedef void (__stdcall *gl_tex_image2d_func)(GLenum, GLint, GLint, GLsizei, GLsizei, GLint, GLenum, GLenum, const GLvoid*);
nuclear@14: #endif
nuclear@14: 
nuclear@14: static gl_gen_textures_func gl_gen_textures;
nuclear@14: static gl_bind_texture_func gl_bind_texture;
nuclear@14: static gl_tex_parameteri_func gl_tex_parameteri;
nuclear@14: static gl_tex_image2d_func gl_tex_image2d;
nuclear@14: 
nuclear@14: static int load_glfunc(void);
nuclear@14: 
nuclear@14: unsigned int img_fmt_glfmt(enum img_fmt fmt)
nuclear@14: {
nuclear@14: 	switch(fmt) {
nuclear@14: 	case IMG_FMT_GREY8:
nuclear@14: 	case IMG_FMT_GREYF:
nuclear@14: 		return GL_LUMINANCE;
nuclear@14: 
nuclear@14: 	case IMG_FMT_RGB24:
nuclear@14: 	case IMG_FMT_RGBF:
nuclear@14: 		return GL_RGB;
nuclear@14: 
nuclear@14: 	case IMG_FMT_RGBA32:
nuclear@14: 	case IMG_FMT_RGBAF:
nuclear@14: 		return GL_RGBA;
nuclear@14: 
nuclear@14: 	default:
nuclear@14: 		break;
nuclear@14: 	}
nuclear@14: 	return 0;
nuclear@14: }
nuclear@14: 
nuclear@14: unsigned int img_fmt_gltype(enum img_fmt fmt)
nuclear@14: {
nuclear@14: 	switch(fmt) {
nuclear@14: 	case IMG_FMT_GREY8:
nuclear@14: 	case IMG_FMT_RGB24:
nuclear@14: 	case IMG_FMT_RGBA32:
nuclear@14: 		return GL_UNSIGNED_BYTE;
nuclear@14: 
nuclear@14: 	case IMG_FMT_GREYF:
nuclear@14: 	case IMG_FMT_RGBF:
nuclear@14: 	case IMG_FMT_RGBAF:
nuclear@14: 		return GL_FLOAT;
nuclear@14: 
nuclear@14: 	default:
nuclear@14: 		break;
nuclear@14: 	}
nuclear@14: 	return 0;
nuclear@14: }
nuclear@14: 
nuclear@14: unsigned int img_fmt_glintfmt(enum img_fmt fmt)
nuclear@14: {
nuclear@14: 	switch(fmt) {
nuclear@14: 	case IMG_FMT_GREY8:
nuclear@14: 		return GL_LUMINANCE;
nuclear@14: 	case IMG_FMT_RGB24:
nuclear@14: 		return GL_RGB;
nuclear@14: 	case IMG_FMT_RGBA32:
nuclear@14: 		return GL_RGBA;
nuclear@14: 	case IMG_FMT_GREYF:
nuclear@14: 		return GL_LUMINANCE32F;
nuclear@14: 	case IMG_FMT_RGBF:
nuclear@14: 		return GL_RGB32F;
nuclear@14: 	case IMG_FMT_RGBAF:
nuclear@14: 		return GL_RGBA32F;
nuclear@14: 	default:
nuclear@14: 		break;
nuclear@14: 	}
nuclear@14: 	return 0;
nuclear@14: }
nuclear@14: 
nuclear@14: unsigned int img_glfmt(struct img_pixmap *img)
nuclear@14: {
nuclear@14: 	return img_fmt_glfmt(img->fmt);
nuclear@14: }
nuclear@14: 
nuclear@14: unsigned int img_gltype(struct img_pixmap *img)
nuclear@14: {
nuclear@14: 	return img_fmt_gltype(img->fmt);
nuclear@14: }
nuclear@14: 
nuclear@14: unsigned int img_glintfmt(struct img_pixmap *img)
nuclear@14: {
nuclear@14: 	return img_fmt_glintfmt(img->fmt);
nuclear@14: }
nuclear@14: 
nuclear@14: unsigned int img_gltexture(struct img_pixmap *img)
nuclear@14: {
nuclear@14: 	unsigned int tex;
nuclear@14: 	unsigned int intfmt, fmt, type;
nuclear@14: 
nuclear@14: 	if(!gl_gen_textures) {
nuclear@14: 		if(load_glfunc() == -1) {
nuclear@14: 			fprintf(stderr, "imago: failed to initialize the OpenGL helpers\n");
nuclear@14: 			return 0;
nuclear@14: 		}
nuclear@14: 	}
nuclear@14: 
nuclear@14: 	intfmt = img_glintfmt(img);
nuclear@14: 	fmt = img_glfmt(img);
nuclear@14: 	type = img_gltype(img);
nuclear@14: 
nuclear@14: 	gl_gen_textures(1, &tex);
nuclear@14: 	gl_bind_texture(GL_TEXTURE_2D, tex);
nuclear@14: 	gl_tex_parameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
nuclear@14: 	gl_tex_parameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
nuclear@14: 	gl_tex_parameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
nuclear@14: 	gl_tex_parameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
nuclear@14: 	gl_tex_image2d(GL_TEXTURE_2D, 0, intfmt, img->width, img->height, 0, fmt, type, img->pixels);
nuclear@14: 	return tex;
nuclear@14: }
nuclear@14: 
nuclear@14: unsigned int img_gltexture_load(const char *fname)
nuclear@14: {
nuclear@14: 	struct img_pixmap img;
nuclear@14: 	unsigned int tex;
nuclear@14: 
nuclear@14: 	img_init(&img);
nuclear@14: 	if(img_load(&img, fname) == -1) {
nuclear@14: 		img_destroy(&img);
nuclear@14: 		return 0;
nuclear@14: 	}
nuclear@14: 
nuclear@14: 	tex = img_gltexture(&img);
nuclear@14: 	img_destroy(&img);
nuclear@14: 	return tex;
nuclear@14: }
nuclear@14: 
nuclear@14: unsigned int img_gltexture_read_file(FILE *fp)
nuclear@14: {
nuclear@14: 	struct img_pixmap img;
nuclear@14: 	unsigned int tex;
nuclear@14: 
nuclear@14: 	img_init(&img);
nuclear@14: 	if(img_read_file(&img, fp) == -1) {
nuclear@14: 		img_destroy(&img);
nuclear@14: 		return 0;
nuclear@14: 	}
nuclear@14: 
nuclear@14: 	tex = img_gltexture(&img);
nuclear@14: 	img_destroy(&img);
nuclear@14: 	return tex;
nuclear@14: }
nuclear@14: 
nuclear@14: unsigned int img_gltexture_read(struct img_io *io)
nuclear@14: {
nuclear@14: 	struct img_pixmap img;
nuclear@14: 	unsigned int tex;
nuclear@14: 
nuclear@14: 	img_init(&img);
nuclear@14: 	if(img_read(&img, io) == -1) {
nuclear@14: 		img_destroy(&img);
nuclear@14: 		return 0;
nuclear@14: 	}
nuclear@14: 
nuclear@14: 	tex = img_gltexture(&img);
nuclear@14: 	img_destroy(&img);
nuclear@14: 	return tex;
nuclear@14: }
nuclear@14: 
nuclear@14: #if defined(__unix__) || defined(__APPLE__)
nuclear@14: #ifndef __USE_GNU
nuclear@14: #define __USE_GNU
nuclear@14: #endif
nuclear@14: 
nuclear@14: #include <dlfcn.h>
nuclear@14: #endif
nuclear@14: #ifdef WIN32
nuclear@14: #include <windows.h>
nuclear@14: #endif
nuclear@14: 
nuclear@14: static int load_glfunc(void)
nuclear@14: {
nuclear@14: #if defined(__unix__) || defined(__APPLE__)
nuclear@14: 	gl_gen_textures = (gl_gen_textures_func)dlsym(RTLD_DEFAULT, "glGenTextures");
nuclear@14: 	gl_bind_texture = (gl_bind_texture_func)dlsym(RTLD_DEFAULT, "glBindTexture");
nuclear@14: 	gl_tex_parameteri = (gl_tex_parameteri_func)dlsym(RTLD_DEFAULT, "glTexParameteri");
nuclear@14: 	gl_tex_image2d = (gl_tex_image2d_func)dlsym(RTLD_DEFAULT, "glTexImage2D");
nuclear@14: #endif
nuclear@14: 
nuclear@14: #ifdef WIN32
nuclear@14: 	HANDLE dll = LoadLibrary("opengl32.dll");
nuclear@14: 	if(dll) {
nuclear@14: 		gl_gen_textures = (gl_gen_textures_func)GetProcAddress(dll, "glGenTextures");
nuclear@14: 		gl_bind_texture = (gl_bind_texture_func)GetProcAddress(dll, "glBindTexture");
nuclear@14: 		gl_tex_parameteri = (gl_tex_parameteri_func)GetProcAddress(dll, "glTexParameteri");
nuclear@14: 		gl_tex_image2d = (gl_tex_image2d_func)GetProcAddress(dll, "glTexImage2D");
nuclear@14: 	}
nuclear@14: #endif
nuclear@14: 
nuclear@14: 	return (gl_gen_textures && gl_bind_texture && gl_tex_parameteri && gl_tex_image2d) ? 0 : -1;
nuclear@14: }