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gfx_opengl_legacy.c
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gfx_opengl_legacy.c
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#ifdef RAPI_GL_LEGACY
#include <stdint.h>
#include <stdbool.h>
#include <assert.h>
#ifndef _LANGUAGE_C
# define _LANGUAGE_C
#endif
#include <PR/gbi.h>
#ifdef __MINGW32__
# define FOR_WINDOWS 1
#else
# define FOR_WINDOWS 0
#endif
#include <SDL2/SDL.h>
#if FOR_WINDOWS || defined(OSX_BUILD)
# define GLEW_STATIC
# include <GL/glew.h>
#endif
#if !defined(__MORPHOS__)
#define GL_GLEXT_PROTOTYPES 1
#else
#include <proto/tinygl.h> // workaround for new/testing tinygl sdk's
#endif
#include <SDL2/SDL_opengl.h>
// redefine this if using a different GL loader
#define mglGetProcAddress(name) SDL_GL_GetProcAddress(name)
// we'll define and load it manually in init, just in case
typedef void (*PFNMGLFOGCOORDPOINTERPROC)(GLenum type, GLsizei stride, const void *pointer);
static PFNMGLFOGCOORDPOINTERPROC mglFogCoordPointer = NULL;
// since these can have different names, might as well redefine them to a single one
#undef GL_FOG_COORD_SRC
#undef GL_FOG_COORD
#undef GL_FOG_COORD_ARRAY
#define GL_FOG_COORD_SRC 0x8450
#define GL_FOG_COORD 0x8451
#define GL_FOG_COORD_ARRAY 0x8457
#include "../platform.h"
#include "gfx_cc.h"
#include "gfx_rendering_api.h"
#include "macros.h"
enum MixFlags {
SH_MF_OVERRIDE_ALPHA = 1,
SH_MF_MULTIPLY = 2,
SH_MF_MIX = 4,
SH_MF_SINGLE = 8,
SH_MF_MULTIPLY_ALPHA = 16,
SH_MF_MIX_ALPHA = 32,
SH_MF_SINGLE_ALPHA = 64,
SH_MF_INPUT_ALPHA = 128,
};
enum MixType {
SH_MT_NONE,
SH_MT_TEXTURE,
SH_MT_COLOR,
SH_MT_TEXTURE_TEXTURE,
SH_MT_TEXTURE_COLOR,
SH_MT_COLOR_COLOR,
};
struct ShaderProgram {
uint32_t shader_id;
enum MixType mix;
uint32_t mix_flags;
bool texture_used[2];
int num_inputs;
};
static struct ShaderProgram shader_program_pool[64];
static uint8_t shader_program_pool_size;
static struct ShaderProgram *cur_shader = NULL;
static const float *cur_buf = NULL;
static const float *cur_fog_ofs = NULL;
static size_t cur_buf_size = 0;
static size_t cur_buf_num_tris = 0;
static size_t cur_buf_stride = 0;
static bool gl_blend = false;
static bool gl_adv_fog = false;
static const float c_white[] = { 1.f, 1.f, 1.f, 1.f };
static bool gfx_opengl_z_is_from_0_to_1(void) {
return false;
}
#define TEXENV_COMBINE_ON() glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE)
#define TEXENV_COMBINE_OFF() glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE)
#define TEXENV_COMBINE_OP(num, cval, aval) \
do { \
glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND ## num ## _RGB, cval); \
glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND ## num ## _ALPHA, aval); \
} while (0)
#define TEXENV_COMBINE_SET1(what, mode, val) \
do { \
glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_ ## what, mode); \
glTexEnvi(GL_TEXTURE_ENV, GL_SRC0_ ## what, val); \
} while (0)
#define TEXENV_COMBINE_SET2(what, mode, val1, val2) \
do { \
glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_ ## what, mode); \
glTexEnvi(GL_TEXTURE_ENV, GL_SRC0_ ## what, val1); \
glTexEnvi(GL_TEXTURE_ENV, GL_SRC1_ ## what, val2); \
} while (0)
#define TEXENV_COMBINE_SET3(what, mode, val1, val2, val3) \
do { \
glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_ ## what, mode); \
glTexEnvi(GL_TEXTURE_ENV, GL_SRC0_ ## what, val1); \
glTexEnvi(GL_TEXTURE_ENV, GL_SRC1_ ## what, val2); \
glTexEnvi(GL_TEXTURE_ENV, GL_SRC2_ ## what, val3); \
} while (0)
static inline void texenv_set_texture_color(struct ShaderProgram *prg) {
glActiveTexture(GL_TEXTURE0);
if (prg->mix_flags & SH_MF_OVERRIDE_ALPHA) {
TEXENV_COMBINE_ON();
if (prg->mix_flags & SH_MF_SINGLE_ALPHA) {
if (prg->mix_flags & SH_MF_MULTIPLY) {
// keep the alpha but modulate the color
const GLenum alphasrc = (prg->mix_flags & SH_MF_INPUT_ALPHA) ? GL_PRIMARY_COLOR : GL_TEXTURE;
TEXENV_COMBINE_SET2(RGB, GL_MODULATE, GL_TEXTURE, GL_PRIMARY_COLOR);
TEXENV_COMBINE_SET1(ALPHA, GL_REPLACE, alphasrc);
} else {
// somehow makes it keep the color while taking the alpha from primary color
TEXENV_COMBINE_SET1(RGB, GL_REPLACE, GL_TEXTURE);
}
} else { // if (prg->mix_flags & SH_MF_SINGLE) {
if (prg->mix_flags & SH_MF_MULTIPLY_ALPHA) {
// modulate the alpha but keep the color
TEXENV_COMBINE_SET2(ALPHA, GL_MODULATE, GL_TEXTURE, GL_PRIMARY_COLOR);
TEXENV_COMBINE_SET1(RGB, GL_REPLACE, GL_TEXTURE);
} else {
// somehow makes it keep the alpha
TEXENV_COMBINE_SET1(ALPHA, GL_REPLACE, GL_TEXTURE);
}
}
// TODO: MIX and the other one
} else if (prg->mix_flags & SH_MF_MULTIPLY) {
// TODO: is this right?
TEXENV_COMBINE_OFF();
} else if (prg->mix_flags & SH_MF_MIX) {
TEXENV_COMBINE_ON();
// HACK: determine this using flags and not this crap
if (prg->num_inputs > 1) {
// out.rgb = mix(color0.rgb, color1.rgb, texel0.rgb);
// no color1 tho, so mix with white (texenv color is set in init())
TEXENV_COMBINE_OP(2, GL_SRC_COLOR, GL_SRC_ALPHA);
TEXENV_COMBINE_SET3(RGB, GL_INTERPOLATE, GL_CONSTANT, GL_PRIMARY_COLOR, GL_TEXTURE);
TEXENV_COMBINE_SET1(ALPHA, GL_REPLACE, GL_CONSTANT);
} else {
// out.rgb = mix(color0.rgb, texel0.rgb, texel0.a);
TEXENV_COMBINE_OP(2, GL_SRC_ALPHA, GL_SRC_ALPHA);
TEXENV_COMBINE_SET3(RGB, GL_INTERPOLATE, GL_TEXTURE, GL_PRIMARY_COLOR, GL_TEXTURE);
}
} else {
TEXENV_COMBINE_OFF();
}
}
static inline void texenv_set_texture_texture(UNUSED struct ShaderProgram *prg) {
glActiveTexture(GL_TEXTURE0);
TEXENV_COMBINE_OFF();
glActiveTexture(GL_TEXTURE1);
TEXENV_COMBINE_ON();
// out.rgb = mix(texel0.rgb, texel1.rgb, color0.rgb);
TEXENV_COMBINE_OP(2, GL_SRC_COLOR, GL_SRC_ALPHA);
TEXENV_COMBINE_SET3(RGB, GL_INTERPOLATE, GL_PREVIOUS, GL_TEXTURE, GL_PRIMARY_COLOR);
// out.a = texel0.a;
TEXENV_COMBINE_SET1(ALPHA, GL_REPLACE, GL_PREVIOUS);
}
static void gfx_opengl_apply_shader(struct ShaderProgram *prg) {
const float *ofs = cur_buf;
// vertices are always there
glVertexPointer(4, GL_FLOAT, cur_buf_stride, ofs);
ofs += 4;
// have texture(s), specify same texcoords for every active texture
for (int i = 0; i < 2; ++i) {
if (prg->texture_used[i]) {
glEnable(GL_TEXTURE0 + i);
glClientActiveTexture(GL_TEXTURE0 + i);
glActiveTexture(GL_TEXTURE0 + i);
glEnableClientState(GL_TEXTURE_COORD_ARRAY);
glTexCoordPointer(2, GL_FLOAT, cur_buf_stride, ofs);
glEnable(GL_TEXTURE_2D);
ofs += 2;
}
}
if (prg->shader_id & SHADER_OPT_FOG) {
// fog requested, we can deal with it in one of two ways
if (gl_adv_fog) {
// if GL_EXT_fog_coord is available, use the provided fog factor as scaled depth for GL fog
const float fogrgb[] = { ofs[0], ofs[1], ofs[2] };
glEnable(GL_FOG);
glFogfv(GL_FOG_COLOR, fogrgb); // color is the same for all verts, only intensity is different
glEnableClientState(GL_FOG_COORD_ARRAY);
mglFogCoordPointer(GL_FLOAT, cur_buf_stride, ofs + 3); // point it to alpha, which is fog factor
} else {
// if there's no fog coords available, blend it on top of normal tris later
cur_fog_ofs = ofs;
}
ofs += 4;
}
if (prg->num_inputs) {
// have colors
// TODO: more than one color (maybe glSecondaryColorPointer?)
// HACK: if there's a texture and two colors, one of them is likely for speculars or some shit (see mario head)
// if there's two colors but no texture, the real color is likely the second one
const int hack = (prg->num_inputs > 1) * (4 - (int)prg->texture_used[0]);
glEnableClientState(GL_COLOR_ARRAY);
glColorPointer(4, GL_FLOAT, cur_buf_stride, ofs + hack);
ofs += 4 * prg->num_inputs;
}
if (prg->shader_id & SHADER_OPT_TEXTURE_EDGE) {
// (horrible) alpha discard
glEnable(GL_ALPHA_TEST);
glAlphaFunc(GL_GREATER, 0.3f);
}
// configure formulae
switch (prg->mix) {
case SH_MT_TEXTURE:
glActiveTexture(GL_TEXTURE0);
TEXENV_COMBINE_OFF();
break;
case SH_MT_TEXTURE_COLOR:
texenv_set_texture_color(prg);
break;
case SH_MT_TEXTURE_TEXTURE:
texenv_set_texture_texture(prg);
break;
default:
break;
}
}
static void gfx_opengl_unload_shader(struct ShaderProgram *old_prg) {
if (cur_shader == old_prg || old_prg == NULL)
cur_shader = NULL;
glClientActiveTexture(GL_TEXTURE0);
glActiveTexture(GL_TEXTURE0);
glDisable(GL_TEXTURE_2D);
glDisableClientState(GL_TEXTURE_COORD_ARRAY);
glClientActiveTexture(GL_TEXTURE1);
glActiveTexture(GL_TEXTURE1);
glDisable(GL_TEXTURE_2D);
glDisableClientState(GL_TEXTURE_COORD_ARRAY);
glDisable(GL_TEXTURE1);
glDisable(GL_TEXTURE0);
glDisable(GL_TEXTURE_2D);
glDisable(GL_ALPHA_TEST);
glDisable(GL_FOG);
cur_fog_ofs = NULL; // clear fog colors
glDisableClientState(GL_COLOR_ARRAY);
if (gl_adv_fog) glDisableClientState(GL_FOG_COORD_ARRAY);
}
static void gfx_opengl_load_shader(struct ShaderProgram *new_prg) {
cur_shader = new_prg;
// gfx_opengl_apply_shader(cur_shader);
}
static struct ShaderProgram *gfx_opengl_create_and_load_new_shader(uint32_t shader_id) {
uint8_t c[2][4];
for (int i = 0; i < 4; i++) {
c[0][i] = (shader_id >> (i * 3)) & 7;
c[1][i] = (shader_id >> (12 + i * 3)) & 7;
}
bool used_textures[2] = {0, 0};
int num_inputs = 0;
for (int i = 0; i < 2; i++) {
for (int j = 0; j < 4; j++) {
if (c[i][j] >= SHADER_INPUT_1 && c[i][j] <= SHADER_INPUT_4) {
if (c[i][j] > num_inputs) {
num_inputs = c[i][j];
}
}
if (c[i][j] == SHADER_TEXEL0 || c[i][j] == SHADER_TEXEL0A) {
used_textures[0] = true;
}
if (c[i][j] == SHADER_TEXEL1) {
used_textures[1] = true;
}
}
}
const bool color_alpha_same = (shader_id & 0xfff) == ((shader_id >> 12) & 0xfff);
const bool do_multiply[2] = {c[0][1] == 0 && c[0][3] == 0, c[1][1] == 0 && c[1][3] == 0};
const bool do_mix[2] = {c[0][1] == c[0][3], c[1][1] == c[1][3]};
const bool do_single[2] = {c[0][2] == 0, c[1][2] == 0};
struct ShaderProgram *prg = &shader_program_pool[shader_program_pool_size++];
prg->shader_id = shader_id;
prg->num_inputs = num_inputs;
prg->texture_used[0] = used_textures[0];
prg->texture_used[1] = used_textures[1];
if (used_textures[0] && used_textures[1])
prg->mix = SH_MT_TEXTURE_TEXTURE;
else if (used_textures[0] && num_inputs)
prg->mix = SH_MT_TEXTURE_COLOR;
else if (used_textures[0])
prg->mix = SH_MT_TEXTURE;
else if (num_inputs > 1)
prg->mix = SH_MT_COLOR_COLOR;
else if (num_inputs)
prg->mix = SH_MT_COLOR;
if (do_single[0]) prg->mix_flags |= SH_MF_SINGLE;
if (do_multiply[0]) prg->mix_flags |= SH_MF_MULTIPLY;
if (do_mix[0]) prg->mix_flags |= SH_MF_MIX;
if (!color_alpha_same && (shader_id & SHADER_OPT_ALPHA)) {
prg->mix_flags |= SH_MF_OVERRIDE_ALPHA;
if (do_single[1]) prg->mix_flags |= SH_MF_SINGLE_ALPHA;
if (do_multiply[1]) prg->mix_flags |= SH_MF_MULTIPLY_ALPHA;
if (do_mix[1]) prg->mix_flags |= SH_MF_MIX_ALPHA;
if (c[1][3] < SHADER_TEXEL0) prg->mix_flags |= SH_MF_INPUT_ALPHA;
}
gfx_opengl_load_shader(prg);
return prg;
}
static struct ShaderProgram *gfx_opengl_lookup_shader(uint32_t shader_id) {
for (size_t i = 0; i < shader_program_pool_size; i++) {
if (shader_program_pool[i].shader_id == shader_id) {
return &shader_program_pool[i];
}
}
return NULL;
}
static void gfx_opengl_shader_get_info(struct ShaderProgram *prg, uint8_t *num_inputs, bool used_textures[2]) {
*num_inputs = prg->num_inputs;
used_textures[0] = prg->texture_used[0];
used_textures[1] = prg->texture_used[1];
}
static GLuint gfx_opengl_new_texture(void) {
GLuint ret;
glGenTextures(1, &ret);
return ret;
}
static void gfx_opengl_select_texture(int tile, GLuint texture_id) {
glActiveTexture(GL_TEXTURE0 + tile);
glBindTexture(GL_TEXTURE_2D, texture_id);
}
static void gfx_opengl_upload_texture(uint8_t *rgba32_buf, int width, int height) {
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, rgba32_buf);
}
static uint32_t gfx_cm_to_opengl(uint32_t val) {
if (val & G_TX_CLAMP)
return GL_CLAMP_TO_EDGE;
return (val & G_TX_MIRROR) ? GL_MIRRORED_REPEAT : GL_REPEAT;
}
static void gfx_opengl_set_sampler_parameters(int tile, bool linear_filter, uint32_t cms, uint32_t cmt) {
const GLenum filter = linear_filter ? GL_LINEAR : GL_NEAREST;
glActiveTexture(GL_TEXTURE0 + tile);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, filter);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, filter);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, gfx_cm_to_opengl(cms));
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, gfx_cm_to_opengl(cmt));
}
static void gfx_opengl_set_depth_test(bool depth_test) {
if (depth_test) {
glEnable(GL_DEPTH_TEST);
} else {
glDisable(GL_DEPTH_TEST);
}
}
static void gfx_opengl_set_depth_mask(bool z_upd) {
glDepthMask(z_upd ? GL_TRUE : GL_FALSE);
}
static void gfx_opengl_set_zmode_decal(bool zmode_decal) {
if (zmode_decal) {
glPolygonOffset(-2, -2);
glEnable(GL_POLYGON_OFFSET_FILL);
} else {
glPolygonOffset(0, 0);
glDisable(GL_POLYGON_OFFSET_FILL);
}
}
static void gfx_opengl_set_viewport(int x, int y, int width, int height) {
glViewport(x, y, width, height);
}
static void gfx_opengl_set_scissor(int x, int y, int width, int height) {
glScissor(x, y, width, height);
}
static void gfx_opengl_set_use_alpha(bool use_alpha) {
gl_blend = use_alpha;
if (use_alpha) {
glEnable(GL_BLEND);
} else {
glDisable(GL_BLEND);
}
}
// draws the same triangles as plain fog color + fog intensity as alpha
// on top of the normal tris and blends them to achieve sort of the same effect
// as fog would
static inline void gfx_opengl_blend_fog_tris(void) {
// if a texture was used, replace it with fog color instead, but still keep the alpha
if (cur_shader->texture_used[0]) {
glActiveTexture(GL_TEXTURE0);
TEXENV_COMBINE_ON();
// out.rgb = input0.rgb
TEXENV_COMBINE_SET1(RGB, GL_REPLACE, GL_PRIMARY_COLOR);
// out.a = texel0.a * input0.a
TEXENV_COMBINE_SET2(ALPHA, GL_MODULATE, GL_TEXTURE, GL_PRIMARY_COLOR);
}
glEnableClientState(GL_COLOR_ARRAY); // enable color array temporarily
glColorPointer(4, GL_FLOAT, cur_buf_stride, cur_fog_ofs); // set fog colors as primary colors
if (!gl_blend) glEnable(GL_BLEND); // enable blending temporarily
glDepthFunc(GL_LEQUAL); // Z is the same as the base triangles
glDrawArrays(GL_TRIANGLES, 0, 3 * cur_buf_num_tris);
glDepthFunc(GL_LESS); // set back to default
if (!gl_blend) glDisable(GL_BLEND); // disable blending if it was disabled
glDisableClientState(GL_COLOR_ARRAY); // will get reenabled later anyway
}
static void gfx_opengl_draw_triangles(float buf_vbo[], size_t buf_vbo_len, size_t buf_vbo_num_tris) {
//printf("flushing %d tris\n", buf_vbo_num_tris);
cur_buf = buf_vbo;
cur_buf_size = buf_vbo_len * 4;
cur_buf_num_tris = buf_vbo_num_tris;
cur_buf_stride = cur_buf_size / (3 * cur_buf_num_tris);
gfx_opengl_apply_shader(cur_shader);
glDrawArrays(GL_TRIANGLES, 0, 3 * cur_buf_num_tris);
// cur_fog_ofs is only set if GL_EXT_fog_coord isn't used
if (cur_fog_ofs) gfx_opengl_blend_fog_tris();
}
static inline bool gl_check_ext(const char *name) {
static const char *extstr = NULL;
if (extstr == NULL)
extstr = (const char *)glGetString(GL_EXTENSIONS);
if (!strstr(extstr, name)) {
fprintf(stderr, "GL extension not supported: %s\n", name);
return false;
}
printf("GL extension detected: %s\n", name);
return true;
}
static inline bool gl_get_version(int *major, int *minor, bool *is_es) {
const char *vstr = (const char *)glGetString(GL_VERSION);
if (!vstr || !vstr[0]) return false;
if (!strncmp(vstr, "OpenGL ES ", 10)) {
vstr += 10;
*is_es = true;
} else if (!strncmp(vstr, "OpenGL ES-CM ", 13)) {
vstr += 13;
*is_es = true;
}
return (sscanf(vstr, "%d.%d", major, minor) == 2);
}
static void gfx_opengl_init(void) {
#if FOR_WINDOWS || defined(OSX_BUILD)
GLenum err;
if ((err = glewInit()) != GLEW_OK)
sys_fatal("could not init GLEW:\n%s", glewGetErrorString(err));
#endif
// check GL version
int vmajor, vminor;
bool is_es = false;
gl_get_version(&vmajor, &vminor, &is_es);
if (vmajor < 2 && vminor < 2 && !is_es)
sys_fatal("OpenGL 1.2+ is required.\nReported version: %s%d.%d", is_es ? "ES" : "", vmajor, vminor);
// check extensions that we need
const bool supported =
gl_check_ext("GL_ARB_multitexture") &&
gl_check_ext("GL_ARB_texture_env_combine");
if (!supported)
sys_fatal("required GL extensions are not supported");
gl_adv_fog = false;
// check whether we can use advanced fog shit
const bool fog_ext =
vmajor > 1 || vminor > 3 ||
gl_check_ext("GL_EXT_fog_coord") ||
gl_check_ext("GL_ARB_fog_coord");
if (fog_ext) {
// try to load manually, as this might be an extension, and even then the ext list may lie
mglFogCoordPointer = mglGetProcAddress("glFogCoordPointer");
if (!mglFogCoordPointer) mglFogCoordPointer = mglGetProcAddress("glFogCoordPointerEXT");
if (!mglFogCoordPointer) mglFogCoordPointer = mglGetProcAddress("glFogCoordPointerARB");
if (!mglFogCoordPointer)
printf("glFogCoordPointer is not actually available, it won't be used.\n");
else
gl_adv_fog = true; // appears to be all good
}
printf("GL_VERSION = %s\n", glGetString(GL_VERSION));
printf("GL_EXTENSIONS =\n%s\n", glGetString(GL_EXTENSIONS));
if (gl_adv_fog) {
// set fog params, they never change
printf("GL_EXT_fog_coord available, using that for fog\n");
glFogi(GL_FOG_COORD_SRC, GL_FOG_COORD);
glFogi(GL_FOG_MODE, GL_LINEAR);
glFogf(GL_FOG_START, 0.0f);
glFogf(GL_FOG_END, 1.0f);
}
// these also never change
glEnableClientState(GL_VERTEX_ARRAY);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glTexEnvfv(GL_TEXTURE_ENV, GL_TEXTURE_ENV_COLOR, c_white);
TEXENV_COMBINE_OP(0, GL_SRC_COLOR, GL_SRC_ALPHA);
TEXENV_COMBINE_OP(1, GL_SRC_COLOR, GL_SRC_ALPHA);
}
static void gfx_opengl_start_frame(void) {
glDisable(GL_SCISSOR_TEST);
glDepthMask(GL_TRUE); // Must be set to clear Z-buffer
glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glEnable(GL_SCISSOR_TEST);
}
static void gfx_opengl_shutdown(void) {
}
struct GfxRenderingAPI gfx_opengl_api = {
gfx_opengl_z_is_from_0_to_1,
gfx_opengl_unload_shader,
gfx_opengl_load_shader,
gfx_opengl_create_and_load_new_shader,
gfx_opengl_lookup_shader,
gfx_opengl_shader_get_info,
gfx_opengl_new_texture,
gfx_opengl_select_texture,
gfx_opengl_upload_texture,
gfx_opengl_set_sampler_parameters,
gfx_opengl_set_depth_test,
gfx_opengl_set_depth_mask,
gfx_opengl_set_zmode_decal,
gfx_opengl_set_viewport,
gfx_opengl_set_scissor,
gfx_opengl_set_use_alpha,
gfx_opengl_draw_triangles,
gfx_opengl_init,
gfx_opengl_start_frame,
gfx_opengl_shutdown
};
#endif // RAPI_GL_LEGACY