From 817c8a1afffa052284ec7e31fef75f37392c57c8 Mon Sep 17 00:00:00 2001
From: Agent X <44549182+Agent-11@users.noreply.github.com>
Date: Wed, 3 Apr 2024 20:10:10 -0400
Subject: [PATCH] Make OpenGL renderer able to vertex color lightmaps

---
 src/pc/gfx/gfx_opengl.c | 30 ++++++++++++++++++++++--------
 1 file changed, 22 insertions(+), 8 deletions(-)

diff --git a/src/pc/gfx/gfx_opengl.c b/src/pc/gfx/gfx_opengl.c
index 26734241..0daae5fa 100644
--- a/src/pc/gfx/gfx_opengl.c
+++ b/src/pc/gfx/gfx_opengl.c
@@ -39,6 +39,7 @@
 #include "../configfile.h"
 #include "gfx_cc.h"
 #include "gfx_rendering_api.h"
+#include "gfx_pc.h"
 
 #define TEX_CACHE_STEP 512
 
@@ -49,10 +50,11 @@ struct ShaderProgram {
     bool used_textures[2];
     uint8_t num_floats;
     GLint attrib_locations[7];
-    GLint uniform_locations[5];
+    GLint uniform_locations[6];
     uint8_t attrib_sizes[7];
     uint8_t num_attribs;
     bool used_noise;
+    bool used_lightmap;
 };
 
 struct GLTexture {
@@ -92,8 +94,8 @@ static void gfx_opengl_vertex_array_set_attribs(struct ShaderProgram *prg) {
 }
 
 static inline void gfx_opengl_set_shader_uniforms(struct ShaderProgram *prg) {
-    if (prg->used_noise)
-        glUniform1f(prg->uniform_locations[4], (float)frame_count);
+    if (prg->used_noise) { glUniform1f(prg->uniform_locations[4], (float)frame_count); }
+    if (prg->used_lightmap) { glUniform3f(prg->uniform_locations[5], gVertexColor[0] / 255.0f, gVertexColor[1] / 255.0f, gVertexColor[2] / 255.0f); }
 }
 
 static inline void gfx_opengl_set_texture_uniforms(struct ShaderProgram *prg, const int tile) {
@@ -366,7 +368,7 @@ static struct ShaderProgram *gfx_opengl_create_and_load_new_shader(struct ColorC
     }
 
     if ((opt_alpha && opt_dither) || ccf.do_noise) {
-        append_line(fs_buf, &fs_len, "uniform float frame_count;");
+        append_line(fs_buf, &fs_len, "uniform float uFrameCount;");
 
         append_line(fs_buf, &fs_len, "float random(in vec3 value) {");
         append_line(fs_buf, &fs_len, "    float random = dot(sin(value), vec3(12.9898, 78.233, 37.719));");
@@ -374,19 +376,24 @@ static struct ShaderProgram *gfx_opengl_create_and_load_new_shader(struct ColorC
         append_line(fs_buf, &fs_len, "}");
     }
 
+    if (opt_light_map) {
+        append_line(fs_buf, &fs_len, "uniform vec3 uLightmapColor;");
+    }
+
     append_line(fs_buf, &fs_len, "void main() {");
 
     if ((opt_alpha && opt_dither) || ccf.do_noise) {
-        append_line(fs_buf, &fs_len, "float noise = floor(random(floor(vec3(gl_FragCoord.xy, frame_count))) + 0.5);");
+        append_line(fs_buf, &fs_len, "float noise = floor(random(floor(vec3(gl_FragCoord.xy, uFrameCount))) + 0.5);");
     }
 
     if (ccf.used_textures[0]) {
         append_line(fs_buf, &fs_len, "vec4 texVal0 = sampleTex(uTex0, vTexCoord, uTex0Size, uTex0Filter);");
     }
     if (ccf.used_textures[1]) {
-        if (cc->cm.light_map) {
+        if (opt_light_map) {
             append_line(fs_buf, &fs_len, "vec4 texVal1 = sampleTex(uTex1, vLightMap, uTex1Size, uTex1Filter);");
-            append_line(fs_buf, &fs_len, "texVal1.rgb = texVal1.rgb * texVal1.rgb  + texVal1.rgb;");
+            append_line(fs_buf, &fs_len, "texVal0.rgb *= uLightmapColor.rgb;");
+            append_line(fs_buf, &fs_len, "texVal1.rgb = texVal1.rgb * texVal1.rgb + texVal1.rgb;");
         } else {
             append_line(fs_buf, &fs_len, "vec4 texVal1 = sampleTex(uTex1, vTexCoord, uTex1Size, uTex1Filter);");
         }
@@ -542,12 +549,19 @@ static struct ShaderProgram *gfx_opengl_create_and_load_new_shader(struct ColorC
     }
 
     if ((opt_alpha && opt_dither) || ccf.do_noise) {
-        prg->uniform_locations[4] = glGetUniformLocation(shader_program, "frame_count");
+        prg->uniform_locations[4] = glGetUniformLocation(shader_program, "uFrameCount");
         prg->used_noise = true;
     } else {
         prg->used_noise = false;
     }
 
+    if (opt_light_map) {
+        prg->uniform_locations[5] = glGetUniformLocation(shader_program, "uLightmapColor");
+        prg->used_lightmap = true;
+    } else {
+        prg->used_lightmap = false;
+    }
+
     return prg;
 }