source/graphics/wgl/glcontext.cpp

   1 #include <vector>
   2 #include <windows.h>
   3 #include <GL/gl.h>
   4 #include <GL/wglext.h>
   5 #include "glcontext.h"
   6 #include "window_private.h"
   7
   8 using namespace std;
   9
  10 namespace Msp {
  11 namespace Graphics {
  12
  13 typedef HGLRC ContextHandle;
  14
  15 struct GLContext::Private
  16 {
  17         ContextHandle context;
  18 };
  19
  20
  21 void GLContext::platform_init(const GLOptions &opts)
  22 {
  23         HDC dc = GetDC(window.get_private().window);
  24
  25         PIXELFORMATDESCRIPTOR pfd;
  26         memset(&pfd, 0, sizeof(pfd));
  27
  28         pfd.nSize = sizeof(pfd);
  29         pfd.nVersion = 1;
  30         pfd.dwFlags = PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL;
  31         if(opts.doublebuffer)
  32                 pfd.dwFlags |= PFD_DOUBLEBUFFER;
  33         pfd.iPixelType = PFD_TYPE_RGBA;
  34         if(opts.alpha)
  35                 pfd.cAlphaBits = 1;
  36         pfd.cDepthBits = 1;
  37         if(opts.stencil)
  38                 pfd.cStencilBits = 1;
  39
  40         int pf_index = ChoosePixelFormat(dc, &pfd);
  41         if(!pf_index)
  42                 throw unsupported_gl_mode(opts);
  43         SetPixelFormat(dc, pf_index, &pfd);
  44
  45         priv = new Private;
  46         if(opts.forward_compatible || opts.gl_version_major)
  47         {
  48                 ContextHandle fake_context = wglCreateContext(dc);
  49                 wglMakeCurrent(dc, fake_context);
  50
  51                 PFNWGLCREATECONTEXTATTRIBSARBPROC wglCreateContextAttribs = reinterpret_cast<PFNWGLCREATECONTEXTATTRIBSARBPROC>(wglGetProcAddress("wglCreateContextAttribsARB"));
  52                 if(!wglCreateContextAttribs)
  53                         throw unsupported_gl_mode(opts);
  54
  55                 vector<int> ctx_attribs;
  56
  57                 if(opts.forward_compatible)
  58                 {
  59                         ctx_attribs.push_back(WGL_CONTEXT_FLAGS_ARB);
  60                         ctx_attribs.push_back(WGL_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB);
  61                 }
  62
  63                 if(opts.gl_version_major)
  64                 {
  65                         ctx_attribs.push_back(WGL_CONTEXT_MAJOR_VERSION_ARB);
  66                         ctx_attribs.push_back(opts.gl_version_major);
  67                         ctx_attribs.push_back(WGL_CONTEXT_MINOR_VERSION_ARB);
  68                         ctx_attribs.push_back(opts.gl_version_minor);
  69                 }
  70
  71                 ctx_attribs.push_back(0);
  72
  73                 priv->context = wglCreateContextAttribs(dc, 0, &ctx_attribs[0]);
  74                 if(!priv->context)
  75                         throw unsupported_gl_mode(opts);
  76
  77                 wglMakeCurrent(0, 0);
  78                 wglDeleteContext(fake_context);
  79         }
  80         else
  81                 priv->context = wglCreateContext(dc);
  82         wglMakeCurrent(dc, priv->context);
  83
  84         ReleaseDC(window.get_private().window, dc);
  85 }
  86
  87 GLContext::~GLContext()
  88 {
  89         wglMakeCurrent(0, 0);
  90         wglDeleteContext(priv->context);
  91
  92         delete priv;
  93 }
  94
  95 void GLContext::set_swap_interval(unsigned i)
  96 {
  97         PFNWGLSWAPINTERVALEXTPROC wglSwapInterval = reinterpret_cast<PFNWGLSWAPINTERVALEXTPROC>(wglGetProcAddress("wglSwapIntervalEXT"));
  98         if(!wglSwapInterval)
  99                 throw runtime_error("wglSwapIntervalEXT not found");
 100         wglSwapInterval(i);
 101 }
 102
 103 void GLContext::swap_buffers()
 104 {
 105         HDC dc = GetDC(window.get_private().window);
 106         SwapBuffers(dc);
 107         ReleaseDC(window.get_private().window, dc);
 108 }
 109
 110 void GLContext::window_resized(unsigned, unsigned)
 111 { }
 112
 113 } // namespace Graphics
 114 } // namespace Msp