source/gbase/glcontext.cpp

   1 /* $Id$
   2
   3 This file is part of libmspgbase
   4 Copyright © 2007-2008  Mikko Rasa, Mikkosoft Productions
   5 Distributed under the LGPL
   6 */
   7
   8 #include <vector>
   9 #ifdef WIN32
  10 #include <windows.h>
  11 #endif
  12 #ifdef WITH_OPENGL
  13 #include <GL/gl.h>
  14 #ifndef WIN32
  15 #include <GL/glx.h>
  16 #endif
  17 #endif
  18 #include <msp/core/application.h>
  19 #include <msp/core/except.h>
  20 #include "display.h"
  21 #include "glcontext.h"
  22 #include "types.h"
  23 #include "window.h"
  24
  25 namespace Msp {
  26 namespace Graphics {
  27
  28 GLOptions::GLOptions():
  29         alpha(false),
  30         stencil(false),
  31         doublebuffer(true),
  32         multisample(0)
  33 { }
  34
  35
  36 #ifdef WITH_OPENGL
  37 #ifdef WIN32
  38 typedef HGLRC Context;
  39 #else
  40 typedef GLXContext Context;
  41 #endif
  42
  43 struct GLContext::Private
  44 {
  45         Context context;
  46 #ifndef WIN32
  47         // In X11, we need to create a window with the chosen visual
  48         WindowHandle subwnd;
  49 #endif
  50 };
  51 #endif
  52
  53
  54 GLContext::GLContext(Window &wnd, const GLOptions &opts):
  55         display(wnd.get_display()),
  56         window(wnd)
  57 {
  58 #ifdef WITH_OPENGL
  59         priv=new Private;
  60
  61 #ifdef WIN32
  62         HDC dc=GetDC(window.get_handle());
  63
  64         PIXELFORMATDESCRIPTOR pfd;
  65         memset(&pfd, 0, sizeof(pfd));
  66
  67         pfd.nSize=sizeof(pfd);
  68         pfd.nVersion=1;
  69         pfd.dwFlags=PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL;
  70         if(opts.doublebuffer)
  71                 pfd.dwFlags|=PFD_DOUBLEBUFFER;
  72         pfd.iPixelType=PFD_TYPE_RGBA;
  73         if(opts.alpha)
  74                 pfd.cAlphaBits=1;
  75         pfd.cDepthBits=1;
  76         if(opts.stencil)
  77                 pfd.cStencilBits=1;
  78
  79         int pf_index=ChoosePixelFormat(dc, &pfd);
  80         if(!pf_index)
  81                 throw Exception("Couldn't find a suitable pixel format");
  82         SetPixelFormat(dc, pf_index, &pfd);
  83
  84         priv->context=wglCreateContext(dc);
  85         wglMakeCurrent(dc, priv->context);
  86
  87         ReleaseDC(window.get_handle(), dc);
  88 #else
  89         std::vector<int> attribs;
  90
  91         attribs.push_back(GLX_RGBA);
  92         attribs.push_back(GLX_DEPTH_SIZE);
  93         attribs.push_back(1);
  94
  95         if(opts.alpha)
  96         {
  97                 attribs.push_back(GLX_ALPHA_SIZE);
  98                 attribs.push_back(1);
  99         }
 100
 101         if(opts.stencil)
 102         {
 103                 attribs.push_back(GLX_STENCIL_SIZE);
 104                 attribs.push_back(1);
 105         }
 106
 107         if(opts.doublebuffer)
 108                 attribs.push_back(GLX_DOUBLEBUFFER);
 109
 110         if(opts.multisample>0)
 111         {
 112                 attribs.push_back(GLX_SAMPLE_BUFFERS_ARB);
 113                 attribs.push_back(opts.multisample);
 114         }
 115
 116         attribs.push_back(0);
 117
 118         ::Display *dpy=display.get_display();
 119
 120         XVisualInfo *vi=glXChooseVisual(dpy, DefaultScreen(dpy), &attribs.front());
 121         if(!vi)
 122                 throw Exception("Couldn't find a suitable GLX visual");
 123         priv->context=glXCreateContext(dpy, vi, 0, true);
 124
 125         XSetWindowAttributes attr;
 126         attr.colormap=XCreateColormap(dpy, DefaultRootWindow(dpy), vi->visual, AllocNone);
 127
 128         priv->subwnd=XCreateWindow(dpy, window.get_handle(), 0, 0, window.get_width(), window.get_height(), 0, vi->depth, InputOutput, vi->visual, CWColormap, &attr);
 129         XMapWindow(display.get_display(), priv->subwnd);
 130
 131         XFree(vi);
 132
 133         glXMakeCurrent(dpy, priv->subwnd, priv->context);
 134 #endif
 135 #else
 136         (void)wnd;
 137         (void)opts;
 138         throw Exception("OpenGL support not compiled in");
 139 #endif
 140
 141         window.signal_resize.connect(sigc::mem_fun(this, &GLContext::window_resized));
 142 }
 143
 144 GLContext::~GLContext()
 145 {
 146 #ifdef WITH_OPENGL
 147 #ifdef WIN32
 148         wglMakeCurrent(0, 0);
 149         wglDeleteContext(priv->context);
 150 #else
 151         ::Display *dpy=display.get_display();
 152
 153         glXMakeCurrent(dpy, 0, 0);
 154         glXDestroyContext(dpy, priv->context);
 155         XDestroyWindow(dpy, priv->subwnd);
 156 #endif
 157         delete priv;
 158 #endif
 159 }
 160
 161 void GLContext::swap_buffers()
 162 {
 163 #ifdef WITH_OPENGL
 164 #ifdef WIN32
 165         HDC dc=GetDC(window.get_handle());
 166         SwapBuffers(dc);
 167         ReleaseDC(window.get_handle(), dc);
 168 #else
 169         glXSwapBuffers(display.get_display(), priv->subwnd);
 170 #endif
 171 #endif
 172 }
 173
 174 void GLContext::window_resized(unsigned w, unsigned h)
 175 {
 176 #ifdef WITH_OPENGL
 177 #ifndef WIN32
 178         XMoveResizeWindow(display.get_display(), priv->subwnd, 0, 0, w, h);
 179 #endif
 180         glViewport(0, 0, w, h);
 181 #else
 182         (void)w;
 183         (void)h;
 184 #endif
 185 }
 186
 187 } // namespace Graphics
 188 } // namespace Msp