mirror of https://github.com/sm64pc/sm64pc.git
607 lines
20 KiB
C
607 lines
20 KiB
C
#ifdef RAPI_GL_LEGACY
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#include <stdint.h>
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#include <stdbool.h>
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#include <assert.h>
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#ifndef _LANGUAGE_C
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# define _LANGUAGE_C
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#endif
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#include <PR/gbi.h>
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#ifdef __MINGW32__
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# define FOR_WINDOWS 1
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#else
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# define FOR_WINDOWS 0
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#endif
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#include <SDL2/SDL.h>
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#if FOR_WINDOWS || defined(OSX_BUILD)
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# define GLEW_STATIC
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# include <GL/glew.h>
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#endif
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#define GL_GLEXT_PROTOTYPES 1
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#include <SDL2/SDL_opengl.h>
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// redefine this if using a different GL loader
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#define mglGetProcAddress(name) SDL_GL_GetProcAddress(name)
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// we'll define and load it manually in init, just in case
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typedef void (*PFNMGLFOGCOORDPOINTERPROC)(GLenum type, GLsizei stride, const void *pointer);
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static PFNMGLFOGCOORDPOINTERPROC mglFogCoordPointer = NULL;
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// since these can have different names, might as well redefine them to a single one
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#undef GL_FOG_COORD_SRC
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#undef GL_FOG_COORD
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#undef GL_FOG_COORD_ARRAY
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#define GL_FOG_COORD_SRC 0x8450
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#define GL_FOG_COORD 0x8451
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#define GL_FOG_COORD_ARRAY 0x8457
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#include "../platform.h"
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#include "gfx_cc.h"
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#include "gfx_rendering_api.h"
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#include "macros.h"
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enum MixFlags {
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SH_MF_OVERRIDE_ALPHA = 1,
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SH_MF_MULTIPLY = 2,
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SH_MF_MIX = 4,
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SH_MF_SINGLE = 8,
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SH_MF_MULTIPLY_ALPHA = 16,
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SH_MF_MIX_ALPHA = 32,
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SH_MF_SINGLE_ALPHA = 64,
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SH_MF_INPUT_ALPHA = 128,
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};
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enum MixType {
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SH_MT_NONE,
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SH_MT_TEXTURE,
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SH_MT_COLOR,
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SH_MT_TEXTURE_TEXTURE,
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SH_MT_TEXTURE_COLOR,
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SH_MT_COLOR_COLOR,
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};
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struct ShaderProgram {
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uint32_t shader_id;
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enum MixType mix;
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uint32_t mix_flags;
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bool texture_used[2];
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int num_inputs;
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};
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static struct ShaderProgram shader_program_pool[64];
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static uint8_t shader_program_pool_size;
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static struct ShaderProgram *cur_shader = NULL;
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static const float *cur_buf = NULL;
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static const float *cur_fog_ofs = NULL;
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static size_t cur_buf_size = 0;
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static size_t cur_buf_num_tris = 0;
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static size_t cur_buf_stride = 0;
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static bool gl_blend = false;
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static bool gl_adv_fog = false;
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static const float c_white[] = { 1.f, 1.f, 1.f, 1.f };
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static bool gfx_opengl_z_is_from_0_to_1(void) {
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return false;
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}
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#define TEXENV_COMBINE_ON() glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE)
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#define TEXENV_COMBINE_OFF() glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE)
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#define TEXENV_COMBINE_OP(num, cval, aval) \
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do { \
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glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND ## num ## _RGB, cval); \
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glTexEnvi(GL_TEXTURE_ENV, GL_OPERAND ## num ## _ALPHA, aval); \
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} while (0)
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#define TEXENV_COMBINE_SET1(what, mode, val) \
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do { \
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glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_ ## what, mode); \
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glTexEnvi(GL_TEXTURE_ENV, GL_SRC0_ ## what, val); \
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} while (0)
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#define TEXENV_COMBINE_SET2(what, mode, val1, val2) \
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do { \
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glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_ ## what, mode); \
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glTexEnvi(GL_TEXTURE_ENV, GL_SRC0_ ## what, val1); \
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glTexEnvi(GL_TEXTURE_ENV, GL_SRC1_ ## what, val2); \
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} while (0)
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#define TEXENV_COMBINE_SET3(what, mode, val1, val2, val3) \
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do { \
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glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_ ## what, mode); \
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glTexEnvi(GL_TEXTURE_ENV, GL_SRC0_ ## what, val1); \
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glTexEnvi(GL_TEXTURE_ENV, GL_SRC1_ ## what, val2); \
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glTexEnvi(GL_TEXTURE_ENV, GL_SRC2_ ## what, val3); \
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} while (0)
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static inline void texenv_set_texture_color(struct ShaderProgram *prg) {
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glActiveTexture(GL_TEXTURE0);
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if (prg->mix_flags & SH_MF_OVERRIDE_ALPHA) {
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TEXENV_COMBINE_ON();
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if (prg->mix_flags & SH_MF_SINGLE_ALPHA) {
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if (prg->mix_flags & SH_MF_MULTIPLY) {
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// keep the alpha but modulate the color
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const GLenum alphasrc = (prg->mix_flags & SH_MF_INPUT_ALPHA) ? GL_PRIMARY_COLOR : GL_TEXTURE;
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TEXENV_COMBINE_SET2(RGB, GL_MODULATE, GL_TEXTURE, GL_PRIMARY_COLOR);
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TEXENV_COMBINE_SET1(ALPHA, GL_REPLACE, alphasrc);
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} else {
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// somehow makes it keep the color while taking the alpha from primary color
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TEXENV_COMBINE_SET1(RGB, GL_REPLACE, GL_TEXTURE);
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}
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} else { // if (prg->mix_flags & SH_MF_SINGLE) {
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if (prg->mix_flags & SH_MF_MULTIPLY_ALPHA) {
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// modulate the alpha but keep the color
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TEXENV_COMBINE_SET2(ALPHA, GL_MODULATE, GL_TEXTURE, GL_PRIMARY_COLOR);
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TEXENV_COMBINE_SET1(RGB, GL_REPLACE, GL_TEXTURE);
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} else {
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// somehow makes it keep the alpha
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TEXENV_COMBINE_SET1(ALPHA, GL_REPLACE, GL_TEXTURE);
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}
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}
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// TODO: MIX and the other one
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} else if (prg->mix_flags & SH_MF_MULTIPLY) {
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// TODO: is this right?
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TEXENV_COMBINE_OFF();
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} else if (prg->mix_flags & SH_MF_MIX) {
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TEXENV_COMBINE_ON();
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// HACK: determine this using flags and not this crap
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if (prg->num_inputs > 1) {
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// out.rgb = mix(color0.rgb, color1.rgb, texel0.rgb);
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// no color1 tho, so mix with white (texenv color is set in init())
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TEXENV_COMBINE_OP(2, GL_SRC_COLOR, GL_SRC_ALPHA);
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TEXENV_COMBINE_SET3(RGB, GL_INTERPOLATE, GL_CONSTANT, GL_PRIMARY_COLOR, GL_TEXTURE);
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TEXENV_COMBINE_SET1(ALPHA, GL_REPLACE, GL_CONSTANT);
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} else {
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// out.rgb = mix(color0.rgb, texel0.rgb, texel0.a);
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TEXENV_COMBINE_OP(2, GL_SRC_ALPHA, GL_SRC_ALPHA);
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TEXENV_COMBINE_SET3(RGB, GL_INTERPOLATE, GL_TEXTURE, GL_PRIMARY_COLOR, GL_TEXTURE);
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}
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} else {
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TEXENV_COMBINE_OFF();
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}
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}
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static inline void texenv_set_texture_texture(UNUSED struct ShaderProgram *prg) {
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glActiveTexture(GL_TEXTURE0);
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TEXENV_COMBINE_OFF();
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glActiveTexture(GL_TEXTURE1);
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TEXENV_COMBINE_ON();
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// out.rgb = mix(texel0.rgb, texel1.rgb, color0.rgb);
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TEXENV_COMBINE_OP(2, GL_SRC_COLOR, GL_SRC_ALPHA);
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TEXENV_COMBINE_SET3(RGB, GL_INTERPOLATE, GL_PREVIOUS, GL_TEXTURE, GL_PRIMARY_COLOR);
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// out.a = texel0.a;
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TEXENV_COMBINE_SET1(ALPHA, GL_REPLACE, GL_PREVIOUS);
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}
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static void gfx_opengl_apply_shader(struct ShaderProgram *prg) {
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const float *ofs = cur_buf;
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// vertices are always there
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glVertexPointer(4, GL_FLOAT, cur_buf_stride, ofs);
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ofs += 4;
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// have texture(s), specify same texcoords for every active texture
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for (int i = 0; i < 2; ++i) {
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if (prg->texture_used[i]) {
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glEnable(GL_TEXTURE0 + i);
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glClientActiveTexture(GL_TEXTURE0 + i);
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glActiveTexture(GL_TEXTURE0 + i);
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glEnableClientState(GL_TEXTURE_COORD_ARRAY);
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glTexCoordPointer(2, GL_FLOAT, cur_buf_stride, ofs);
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glEnable(GL_TEXTURE_2D);
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ofs += 2;
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}
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}
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if (prg->shader_id & SHADER_OPT_FOG) {
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// fog requested, we can deal with it in one of two ways
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if (gl_adv_fog) {
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// if GL_EXT_fog_coord is available, use the provided fog factor as scaled depth for GL fog
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const float fogrgb[] = { ofs[0], ofs[1], ofs[2] };
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glEnable(GL_FOG);
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glFogfv(GL_FOG_COLOR, fogrgb); // color is the same for all verts, only intensity is different
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glEnableClientState(GL_FOG_COORD_ARRAY);
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mglFogCoordPointer(GL_FLOAT, cur_buf_stride, ofs + 3); // point it to alpha, which is fog factor
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} else {
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// if there's no fog coords available, blend it on top of normal tris later
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cur_fog_ofs = ofs;
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}
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ofs += 4;
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}
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if (prg->num_inputs) {
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// have colors
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// TODO: more than one color (maybe glSecondaryColorPointer?)
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// HACK: if there's a texture and two colors, one of them is likely for speculars or some shit (see mario head)
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// if there's two colors but no texture, the real color is likely the second one
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const int hack = (prg->num_inputs > 1) * (4 - (int)prg->texture_used[0]);
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glEnableClientState(GL_COLOR_ARRAY);
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glColorPointer(4, GL_FLOAT, cur_buf_stride, ofs + hack);
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ofs += 4 * prg->num_inputs;
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}
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if (prg->shader_id & SHADER_OPT_TEXTURE_EDGE) {
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// (horrible) alpha discard
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glEnable(GL_ALPHA_TEST);
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glAlphaFunc(GL_GREATER, 0.3f);
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}
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// configure formulae
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switch (prg->mix) {
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case SH_MT_TEXTURE:
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glActiveTexture(GL_TEXTURE0);
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TEXENV_COMBINE_OFF();
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break;
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case SH_MT_TEXTURE_COLOR:
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texenv_set_texture_color(prg);
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break;
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case SH_MT_TEXTURE_TEXTURE:
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texenv_set_texture_texture(prg);
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break;
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default:
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break;
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}
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}
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static void gfx_opengl_unload_shader(struct ShaderProgram *old_prg) {
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if (cur_shader == old_prg || old_prg == NULL)
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cur_shader = NULL;
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glClientActiveTexture(GL_TEXTURE0);
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glActiveTexture(GL_TEXTURE0);
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glDisable(GL_TEXTURE_2D);
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glDisableClientState(GL_TEXTURE_COORD_ARRAY);
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glClientActiveTexture(GL_TEXTURE1);
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glActiveTexture(GL_TEXTURE1);
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glDisable(GL_TEXTURE_2D);
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glDisableClientState(GL_TEXTURE_COORD_ARRAY);
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glDisable(GL_TEXTURE1);
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glDisable(GL_TEXTURE0);
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glDisable(GL_TEXTURE_2D);
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glDisable(GL_ALPHA_TEST);
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glDisable(GL_FOG);
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cur_fog_ofs = NULL; // clear fog colors
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glDisableClientState(GL_COLOR_ARRAY);
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if (gl_adv_fog) glDisableClientState(GL_FOG_COORD_ARRAY);
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}
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static void gfx_opengl_load_shader(struct ShaderProgram *new_prg) {
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cur_shader = new_prg;
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// gfx_opengl_apply_shader(cur_shader);
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}
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static struct ShaderProgram *gfx_opengl_create_and_load_new_shader(uint32_t shader_id) {
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uint8_t c[2][4];
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for (int i = 0; i < 4; i++) {
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c[0][i] = (shader_id >> (i * 3)) & 7;
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c[1][i] = (shader_id >> (12 + i * 3)) & 7;
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}
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bool used_textures[2] = {0, 0};
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int num_inputs = 0;
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for (int i = 0; i < 2; i++) {
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for (int j = 0; j < 4; j++) {
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if (c[i][j] >= SHADER_INPUT_1 && c[i][j] <= SHADER_INPUT_4) {
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if (c[i][j] > num_inputs) {
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num_inputs = c[i][j];
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}
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}
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if (c[i][j] == SHADER_TEXEL0 || c[i][j] == SHADER_TEXEL0A) {
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used_textures[0] = true;
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}
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if (c[i][j] == SHADER_TEXEL1) {
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used_textures[1] = true;
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}
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}
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}
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const bool color_alpha_same = (shader_id & 0xfff) == ((shader_id >> 12) & 0xfff);
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const bool do_multiply[2] = {c[0][1] == 0 && c[0][3] == 0, c[1][1] == 0 && c[1][3] == 0};
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const bool do_mix[2] = {c[0][1] == c[0][3], c[1][1] == c[1][3]};
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const bool do_single[2] = {c[0][2] == 0, c[1][2] == 0};
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struct ShaderProgram *prg = &shader_program_pool[shader_program_pool_size++];
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prg->shader_id = shader_id;
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prg->num_inputs = num_inputs;
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prg->texture_used[0] = used_textures[0];
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prg->texture_used[1] = used_textures[1];
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if (used_textures[0] && used_textures[1])
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prg->mix = SH_MT_TEXTURE_TEXTURE;
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else if (used_textures[0] && num_inputs)
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prg->mix = SH_MT_TEXTURE_COLOR;
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else if (used_textures[0])
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prg->mix = SH_MT_TEXTURE;
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else if (num_inputs > 1)
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prg->mix = SH_MT_COLOR_COLOR;
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else if (num_inputs)
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prg->mix = SH_MT_COLOR;
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if (do_single[0]) prg->mix_flags |= SH_MF_SINGLE;
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if (do_multiply[0]) prg->mix_flags |= SH_MF_MULTIPLY;
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if (do_mix[0]) prg->mix_flags |= SH_MF_MIX;
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if (!color_alpha_same && (shader_id & SHADER_OPT_ALPHA)) {
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prg->mix_flags |= SH_MF_OVERRIDE_ALPHA;
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if (do_single[1]) prg->mix_flags |= SH_MF_SINGLE_ALPHA;
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if (do_multiply[1]) prg->mix_flags |= SH_MF_MULTIPLY_ALPHA;
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if (do_mix[1]) prg->mix_flags |= SH_MF_MIX_ALPHA;
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if (c[1][3] < SHADER_TEXEL0) prg->mix_flags |= SH_MF_INPUT_ALPHA;
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}
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gfx_opengl_load_shader(prg);
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return prg;
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}
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static struct ShaderProgram *gfx_opengl_lookup_shader(uint32_t shader_id) {
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for (size_t i = 0; i < shader_program_pool_size; i++) {
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if (shader_program_pool[i].shader_id == shader_id) {
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return &shader_program_pool[i];
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}
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}
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return NULL;
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}
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static void gfx_opengl_shader_get_info(struct ShaderProgram *prg, uint8_t *num_inputs, bool used_textures[2]) {
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*num_inputs = prg->num_inputs;
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used_textures[0] = prg->texture_used[0];
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used_textures[1] = prg->texture_used[1];
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}
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static GLuint gfx_opengl_new_texture(void) {
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GLuint ret;
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glGenTextures(1, &ret);
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return ret;
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}
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static void gfx_opengl_select_texture(int tile, GLuint texture_id) {
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glActiveTexture(GL_TEXTURE0 + tile);
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glBindTexture(GL_TEXTURE_2D, texture_id);
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}
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static void gfx_opengl_upload_texture(uint8_t *rgba32_buf, int width, int height) {
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glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, rgba32_buf);
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}
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static uint32_t gfx_cm_to_opengl(uint32_t val) {
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if (val & G_TX_CLAMP)
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return GL_CLAMP_TO_EDGE;
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return (val & G_TX_MIRROR) ? GL_MIRRORED_REPEAT : GL_REPEAT;
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}
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static void gfx_opengl_set_sampler_parameters(int tile, bool linear_filter, uint32_t cms, uint32_t cmt) {
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const GLenum filter = linear_filter ? GL_LINEAR : GL_NEAREST;
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glActiveTexture(GL_TEXTURE0 + tile);
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glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, filter);
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glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, filter);
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glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, gfx_cm_to_opengl(cms));
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glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, gfx_cm_to_opengl(cmt));
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}
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static void gfx_opengl_set_depth_test(bool depth_test) {
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if (depth_test) {
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glEnable(GL_DEPTH_TEST);
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} else {
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glDisable(GL_DEPTH_TEST);
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}
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}
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static void gfx_opengl_set_depth_mask(bool z_upd) {
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glDepthMask(z_upd ? GL_TRUE : GL_FALSE);
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}
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static void gfx_opengl_set_zmode_decal(bool zmode_decal) {
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if (zmode_decal) {
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glPolygonOffset(-2, -2);
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glEnable(GL_POLYGON_OFFSET_FILL);
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} else {
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glPolygonOffset(0, 0);
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glDisable(GL_POLYGON_OFFSET_FILL);
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}
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}
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static void gfx_opengl_set_viewport(int x, int y, int width, int height) {
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glViewport(x, y, width, height);
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}
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static void gfx_opengl_set_scissor(int x, int y, int width, int height) {
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glScissor(x, y, width, height);
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}
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static void gfx_opengl_set_use_alpha(bool use_alpha) {
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gl_blend = use_alpha;
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if (use_alpha) {
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glEnable(GL_BLEND);
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|
} else {
|
|
glDisable(GL_BLEND);
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|
}
|
|
}
|
|
|
|
// draws the same triangles as plain fog color + fog intensity as alpha
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|
// 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
|