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 {
  11
  12 template<typename T>
  13 T get_proc(const char *name)
  14 {
  15         return reinterpret_cast<T>(reinterpret_cast<void *>(wglGetProcAddress(name)));
  16 }
  17
  18 }
  19
  20 namespace Msp {
  21 namespace Graphics {
  22
  23 typedef HGLRC ContextHandle;
  24
  25 struct GLContext::Private
  26 {
  27         ContextHandle context;
  28 };
  29
  30
  31 void GLContext::platform_init(const GLOptions &opts)
  32 {
  33         HDC dc = GetDC(window.get_private().window);
  34
  35         PIXELFORMATDESCRIPTOR pfd;
  36         memset(&pfd, 0, sizeof(pfd));
  37
  38         pfd.nSize = sizeof(pfd);
  39         pfd.nVersion = 1;
  40         pfd.dwFlags = PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL;
  41         if(opts.doublebuffer)
  42                 pfd.dwFlags |= PFD_DOUBLEBUFFER;
  43         pfd.iPixelType = PFD_TYPE_RGBA;
  44         if(opts.alpha)
  45                 pfd.cAlphaBits = 1;
  46         pfd.cDepthBits = 1;
  47         if(opts.stencil)
  48                 pfd.cStencilBits = 1;
  49
  50         int pf_index = ChoosePixelFormat(dc, &pfd);
  51         if(!pf_index)
  52                 throw unsupported_gl_mode(opts);
  53         SetPixelFormat(dc, pf_index, &pfd);
  54
  55         priv = new Private;
  56         if(opts.forward_compatible || opts.gl_version_major)
  57         {
  58                 ContextHandle fake_context = wglCreateContext(dc);
  59                 wglMakeCurrent(dc, fake_context);
  60
  61                 PFNWGLCREATECONTEXTATTRIBSARBPROC wglCreateContextAttribs = get_proc<PFNWGLCREATECONTEXTATTRIBSARBPROC>("wglCreateContextAttribsARB");
  62                 if(!wglCreateContextAttribs)
  63                         throw unsupported_gl_mode(opts);
  64
  65                 vector<int> ctx_attribs;
  66
  67                 if(opts.forward_compatible)
  68                 {
  69                         ctx_attribs.push_back(WGL_CONTEXT_FLAGS_ARB);
  70                         ctx_attribs.push_back(WGL_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB);
  71                 }
  72
  73                 if(opts.core_profile)
  74                 {
  75                         ctx_attribs.push_back(WGL_CONTEXT_PROFILE_MASK_ARB);
  76                         ctx_attribs.push_back(WGL_CONTEXT_CORE_PROFILE_BIT_ARB);
  77                 }
  78
  79                 if(opts.gl_version_major)
  80                 {
  81                         ctx_attribs.push_back(WGL_CONTEXT_MAJOR_VERSION_ARB);
  82                         ctx_attribs.push_back(opts.gl_version_major);
  83                         ctx_attribs.push_back(WGL_CONTEXT_MINOR_VERSION_ARB);
  84                         ctx_attribs.push_back(opts.gl_version_minor);
  85                 }
  86
  87                 ctx_attribs.push_back(0);
  88
  89                 priv->context = wglCreateContextAttribs(dc, 0, &ctx_attribs[0]);
  90                 if(!priv->context)
  91                         throw unsupported_gl_mode(opts);
  92
  93                 wglMakeCurrent(0, 0);
  94                 wglDeleteContext(fake_context);
  95         }
  96         else
  97                 priv->context = wglCreateContext(dc);
  98         wglMakeCurrent(dc, priv->context);
  99
 100         ReleaseDC(window.get_private().window, dc);
 101 }
 102
 103 GLContext::~GLContext()
 104 {
 105         wglMakeCurrent(0, 0);
 106         wglDeleteContext(priv->context);
 107
 108         delete priv;
 109 }
 110
 111 void GLContext::set_swap_interval(unsigned i)
 112 {
 113         PFNWGLSWAPINTERVALEXTPROC wglSwapInterval = get_proc<PFNWGLSWAPINTERVALEXTPROC>("wglSwapIntervalEXT");
 114         if(!wglSwapInterval)
 115                 throw runtime_error("wglSwapIntervalEXT not found");
 116         wglSwapInterval(i);
 117 }
 118
 119 void GLContext::swap_buffers()
 120 {
 121         HDC dc = GetDC(window.get_private().window);
 122         SwapBuffers(dc);
 123         ReleaseDC(window.get_private().window, dc);
 124 }
 125
 126 void GLContext::window_resized(unsigned, unsigned)
 127 { }
 128
 129 } // namespace Graphics
 130 } // namespace Msp