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 static void wireframe(bool enable);
  18
  19 bool init_opengl()
  20 {
  21         if(!glfwInit()) {
  22                 fprintf(stderr, "Failed to initialize GLFW.\n");
  23                 return false;
  24         }
  25
  26         glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 4);
  27         glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 5);
  28         glfwWindowHint(GLFW_SRGB_CAPABLE, GLFW_TRUE);
  29
  30         if(!(win = glfwCreateWindow(win_w, win_h, "glcow", 0, 0))) {
  31                 fprintf(stderr, "Failed to create window.\n");
  32                 return false;
  33         }
  34         glfwMakeContextCurrent(win);
  35
  36         glewInit();
  37
  38         glEnable(GL_DEPTH_TEST);
  39         glEnable(GL_CULL_FACE);
  40         glEnable(GL_FRAMEBUFFER_SRGB); // linear colorspace
  41
  42         gfx_clear = clear;
  43         gfx_viewport = viewport;
  44         gfx_zbuffer = zbuffer;
  45         gfx_cull_face = cull_face;
  46         gfx_reshape = reshape;
  47         gfx_wireframe = wireframe;
  48
  49         // glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
  50         return true;
  51 }
  52
  53 void cleanup_opengl()
  54 {
  55         if(win) {
  56                 glfwDestroyWindow(win);
  57         }
  58         glfwTerminate();
  59 }
  60
  61 static void clear(float r, float g, float b)
  62 {
  63         glClearColor(r, g, b, 1.0);
  64         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  65 }
  66
  67 static void viewport(int x, int y, int width, int height)
  68 {
  69         glViewport(x, y, width, height);
  70 }
  71
  72 static void zbuffer(bool enable)
  73 {
  74         if(enable)
  75                 glEnable(GL_DEPTH_TEST);
  76         else
  77                 glDisable(GL_DEPTH_TEST);
  78 }
  79
  80 static void cull_face(Gfx_cull_face cf)
  81 {
  82         switch(cf) {
  83         case GFX_CULL_NONE:
  84                 glDisable(GL_CULL_FACE);
  85                 break;
  86         case GFX_CULL_FRONT:
  87                 glEnable(GL_CULL_FACE);
  88                 glCullFace(GL_FRONT);
  89                 break;
  90         case GFX_CULL_BACK:
  91                 glEnable(GL_CULL_FACE);
  92                 glCullFace(GL_BACK);
  93                 break;
  94         }
  95 }
  96
  97 static void wireframe(bool enabled)
  98 {
  99         if(enabled)
 100                 glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
 101         else
 102                 glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
 103 }