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

   1 #include <GL/glew.h>
   2 #include <GLFW/glfw3.h>
   3 #include <stdio.h>
   4
   5 #include "gfxapi.h"
   6 #include "opengl/opengl.h"
   7
   8 extern GLFWwindow *win;
   9 extern int win_h;
  10 extern int win_w;
  11
  12 static void clear(float r, float g, float b);
  13 static void viewport(int x, int y, int width, int height);
  14 static void zbuffer(bool enable);
  15 static void cull_face(Gfx_cull_face cf);
  16 static void reshape(int width, int height) {};
  17
  18 bool init_opengl()
  19 {
  20         if(!glfwInit()) {
  21                 fprintf(stderr, "Failed to initialize GLFW.\n");
  22                 return false;
  23         }
  24
  25         glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 4);
  26         glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 5);
  27         glfwWindowHint(GLFW_SRGB_CAPABLE, GLFW_TRUE);
  28
  29         if(!(win = glfwCreateWindow(win_w, win_h, "glcow", 0, 0))) {
  30                 fprintf(stderr, "Failed to create window.\n");
  31                 return false;
  32         }
  33         glfwMakeContextCurrent(win);
  34
  35         glewInit();
  36
  37         glEnable(GL_DEPTH_TEST);
  38         glEnable(GL_CULL_FACE);
  39         glEnable(GL_FRAMEBUFFER_SRGB); // linear colorspace
  40
  41         gfx_clear = clear;
  42         gfx_viewport = viewport;
  43         gfx_zbuffer = zbuffer;
  44         gfx_cull_face = cull_face;
  45         gfx_reshape = reshape;
  46
  47         // glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
  48         return true;
  49 }
  50
  51 void cleanup_opengl()
  52 {
  53         if(win) {
  54                 glfwDestroyWindow(win);
  55         }
  56         glfwTerminate();
  57 }
  58
  59 static void clear(float r, float g, float b)
  60 {
  61         glClearColor(r, g, b, 1.0);
  62         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  63 }
  64
  65 static void viewport(int x, int y, int width, int height)
  66 {
  67         glViewport(x, y, width, height);
  68 }
  69
  70 static void zbuffer(bool enable)
  71 {
  72         if(enable)
  73                 glEnable(GL_DEPTH_TEST);
  74         else
  75                 glDisable(GL_DEPTH_TEST);
  76 }
  77
  78 static void cull_face(Gfx_cull_face cf)
  79 {
  80         switch(cf) {
  81         case GFX_CULL_NONE:
  82                 glDisable(GL_CULL_FACE);
  83                 break;
  84         case GFX_CULL_FRONT:
  85                 glEnable(GL_CULL_FACE);
  86                 glCullFace(GL_FRONT);
  87                 break;
  88         case GFX_CULL_BACK:
  89                 glEnable(GL_CULL_FACE);
  90                 glCullFace(GL_BACK);
  91                 break;
  92         }
  93 }