src/wgl/rtotex/pbuffer.cpp

   1 //////////////////////////////////////////////////////////////////////////////////////////
   2 //      PBUFFER.cpp
   3 //      functions to set up a pbuffer
   4 //      Downloaded from: www.paulsprojects.net
   5 //      Created:        9th September 2002
   6 //
   7 //      Copyright (c) 2006, Paul Baker
   8 //      Distributed under the New BSD Licence. (See accompanying file License.txt or copy at
   9 //      http://www.paulsprojects.net/NewBSDLicense.txt)
  10 //////////////////////////////////////////////////////////////////////////////////////////
  11
  12 #include <windows.h>
  13 #include <GL/glew.h>
  14 #include <GL/wglew.h>
  15 #include <GL/glu.h>
  16 #include "log.h"
  17 #include "pbuffer.h"
  18
  19 extern LOG errorLog;
  20
  21 bool PBUFFER::Init(     int newWidth, int newHeight,
  22                                         int newColorBits, int newDepthBits, int newStencilBits,
  23                                         int numExtraIAttribs, int * extraIAttribList, int * flags)
  24 {
  25         //Check for pbuffer support
  26         if(     !WGLEW_ARB_extensions_string ||
  27                 !WGLEW_ARB_pixel_format ||
  28                 !WGLEW_ARB_pbuffer)
  29         {
  30                 errorLog.OutputError("Extension required for pbuffer unsupported");
  31                 return false;
  32         }
  33
  34         //set class's member variables
  35         width=newWidth;
  36         height=newHeight;
  37         colorBits=newColorBits;
  38         depthBits=newDepthBits;
  39         stencilBits=newStencilBits;
  40
  41         //Get the current device context
  42         HDC hCurrentDC=wglGetCurrentDC();
  43         if(!hCurrentDC)
  44         {
  45                 errorLog.OutputError("Unable to get current Device Context");
  46                 return false;
  47         }
  48
  49
  50         //choose pixel format
  51         GLint pixelFormat;
  52
  53         const int standardIAttribList[]={       WGL_DRAW_TO_PBUFFER_ARB, 1,
  54                                                                                 WGL_COLOR_BITS_ARB, colorBits,
  55                                                                                 WGL_ALPHA_BITS_ARB, colorBits==32 ? 8 : 0,
  56                                                                                 WGL_DEPTH_BITS_ARB, depthBits,
  57                                                                                 WGL_STENCIL_BITS_ARB, stencilBits};
  58         const float fAttribList[]={
  59                                                                                 0};
  60
  61         //add the extraIAttribList to the standardIAttribList
  62         int * iAttribList=new int[sizeof(standardIAttribList)/sizeof(int)+numExtraIAttribs*2+1];
  63         if(!iAttribList)
  64         {
  65                 errorLog.OutputError("Unable to allocate space for iAttribList");
  66                 return false;
  67         }
  68
  69         memcpy( iAttribList, standardIAttribList, sizeof(standardIAttribList));
  70         memcpy( iAttribList+sizeof(standardIAttribList)/sizeof(int),
  71                         extraIAttribList, numExtraIAttribs*2*sizeof(int)+sizeof(int));
  72
  73         //Choose pixel format
  74         unsigned int numFormats;
  75         if(!wglChoosePixelFormatARB(hCurrentDC, iAttribList, fAttribList, 1,
  76                                                                 &pixelFormat, &numFormats))
  77         {
  78                 errorLog.OutputError("Unable to find a pixel format for the pbuffer");
  79                 return false;
  80         }
  81
  82         //Create the pbuffer
  83         hBuffer=wglCreatePbufferARB(hCurrentDC, pixelFormat, width, height, flags);
  84         if(!hBuffer)
  85         {
  86                 errorLog.OutputError("Unable to create pbuffer");
  87                 return false;
  88         }
  89
  90         //Get the pbuffer's device context
  91         hDC=wglGetPbufferDCARB(hBuffer);
  92         if(!hDC)
  93         {
  94                 errorLog.OutputError("Unable to get pbuffer's device context");
  95                 return false;
  96         }
  97
  98         //Create a rendering context for the pbuffer
  99         hRC=wglCreateContext(hDC);
 100         if(!hRC)
 101         {
 102                 errorLog.OutputError("Unable to create pbuffer's rendering context");
 103                 return false;
 104         }
 105
 106         //Set and output the actual pBuffer dimensions
 107         wglQueryPbufferARB(hBuffer, WGL_PBUFFER_WIDTH_ARB, &width);
 108         wglQueryPbufferARB(hBuffer, WGL_PBUFFER_HEIGHT_ARB, &height);
 109         errorLog.OutputSuccess("Pbuffer Created: (%d x %d)", width, height);
 110
 111         return TRUE;                                                                            //success!
 112 }
 113
 114 void PBUFFER::Shutdown(void)
 115 {
 116         if(hRC)                                                                                                 //have a rendering context?
 117         {
 118                 if(!wglDeleteContext(hRC))                                                      //try to delete RC
 119                 {
 120                         errorLog.OutputError("Release of Pbuffer Rendering Context Failed.");
 121                 }
 122
 123                 hRC=NULL;                                                                                       //set RC to NULL
 124         }
 125
 126         if(hDC && !wglReleasePbufferDCARB(hBuffer, hDC))                //Are we able to release DC?
 127         {
 128                 errorLog.OutputError("Release of Pbuffer Device Context Failed.");
 129                 hDC=NULL;
 130         }
 131
 132         if(!wglDestroyPbufferARB(hBuffer))
 133         {
 134                 errorLog.OutputError("Unable to destroy pbuffer");
 135         }
 136 }
 137
 138
 139 bool PBUFFER::MakeCurrent()
 140 {
 141         if(!wglMakeCurrent(hDC, hRC))
 142         {
 143                 errorLog.OutputError("Unable to change current context");
 144                 return false;
 145         }
 146
 147         return true;
 148 }
 149