git.mutantstargoat.com Git - demo/blob - src/opengl/opengl.cc

   1 #include <GL/glew.h>
   2 #include <stdio.h>
   3
   4 #include "gfxapi.h"
   5 #include "opengl/opengl.h"
   6
   7 extern GLFWwindow *win;
   8 extern int win_h;
   9 extern int win_w;
  10
  11 static void clear(float r, float g, float b);
  12 static void viewport(int x, int y, int width, int height);
  13 static void zbuffer(bool enable);
  14 static void cull_face(Gfx_cull_face cf);
  15
  16 bool init_opengl()
  17 {
  18         if(!glfwInit()) {
  19                 fprintf(stderr, "Failed to initialize GLFW.\n");
  20                 return false;
  21         }
  22
  23         glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 4);
  24         glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 5);
  25         glfwWindowHint(GLFW_SRGB_CAPABLE, GLFW_TRUE);
  26
  27         if(!(win = glfwCreateWindow(win_w, win_h, "glcow", 0, 0))) {
  28                 fprintf(stderr, "Failed to create window.\n");
  29                 return false;
  30         }
  31         glfwMakeContextCurrent(win);
  32
  33         glewInit();
  34
  35         glEnable(GL_DEPTH_TEST);
  36         glEnable(GL_CULL_FACE);
  37         glEnable(GL_FRAMEBUFFER_SRGB); // linear colorspace
  38
  39         gfx_clear = clear;
  40         gfx_viewport = viewport;
  41         gfx_zbuffer = zbuffer;
  42         gfx_cull_face = cull_face;
  43
  44         return true;
  45 }
  46
  47 void cleanup_opengl()
  48 {
  49         if(win) {
  50                 glfwDestroyWindow(win);
  51         }
  52         glfwTerminate();
  53 }
  54
  55 static void clear(float r, float g, float b)
  56 {
  57         glClearColor(r, g, b, 1.0);
  58         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  59 }
  60
  61 static void viewport(int x, int y, int width, int height)
  62 {
  63         glViewport(x, y, width, height);
  64 }
  65
  66 static void zbuffer(bool enable)
  67 {
  68         if(enable)
  69                 glEnable(GL_DEPTH_TEST);
  70         else
  71                 glDisable(GL_DEPTH_TEST);
  72 }
  73
  74 static void cull_face(Gfx_cull_face cf)
  75 {
  76         switch(cf) {
  77         case GFX_CULL_NONE:
  78                 glDisable(GL_CULL_FACE);
  79                 break;
  80         case GFX_CULL_FRONT:
  81                 glEnable(GL_CULL_FACE);
  82                 glCullFace(GL_FRONT);
  83                 break;
  84         case GFX_CULL_BACK:
  85                 glEnable(GL_CULL_FACE);
  86                 glCullFace(GL_BACK);
  87                 break;
  88         }
  89 }