src/gallium/frontends/wgl/stw_ext_swapinterval.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2009 VMware, Inc.
   4  * Copyright 2008 VMware, Inc.
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  16  * next paragraph) shall be included in all copies or substantial portions
  17  * of the Software.
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  28
  29 #include <windows.h>
  30
  31 #define WGL_WGLEXT_PROTOTYPES
  32
  33 #include <GL/gl.h>
  34 #include <GL/wglext.h>
  35 #include "util/u_debug.h"
  36 #include "stw_device.h"
  37
  38
  39 /**
  40  * Note that our implementation of swap intervals is a bit of a hack.
  41  * We implement it based on querying the time and Sleep()'ing.  We don't
  42  * sync to the vblank.
  43  */
  44 WINGDIAPI BOOL APIENTRY
  45 wglSwapIntervalEXT(int interval)
  46 {
  47    if (interval < 0) {
  48       SetLastError(ERROR_INVALID_DATA);
  49       return FALSE;
  50    }
  51    if (stw_dev && !os_get_option("WGL_SWAP_INTERVAL")) {
  52       stw_dev->swap_interval = interval;
  53    }
  54    return TRUE;
  55 }
  56
  57
  58 WINGDIAPI int APIENTRY
  59 wglGetSwapIntervalEXT(void)
  60 {
  61    return stw_dev ? stw_dev->swap_interval : 0;
  62 }