glut_overlay.c

mesa-6.5-minigui源码

{
  if (overlay->visAlloced)
    XFree(overlay->vis);
  XDestroyWindow(__glutDisplay, overlay->win);
  glXDestroyContext(__glutDisplay, overlay->ctx);
  if (overlay->colormap) {
    /* Only color index overlays have colormap data structure. */
    __glutFreeColormap(overlay->colormap);
  }
  free(overlay);
}

static XVisualInfo *
determineOverlayVisual(int *treatAsSingle, Bool * visAlloced, void **fbc)
{
  if (__glutDisplayString) {
    XVisualInfo *vi;
    int i;

    /* __glutDisplayString should be NULL except if
       glutInitDisplayString has been called to register a
       different display string.  Calling glutInitDisplayString
       means using a string instead of an integer mask determine 

       the visual to use. Using the function pointer variable
       __glutDetermineVisualFromString below avoids linking in
       the code for implementing glutInitDisplayString (ie,
       glut_dstr.o) unless glutInitDisplayString gets called by
       the application. */

    assert(__glutDetermineVisualFromString);

    /* Try three overlay layers. */
    *visAlloced = False;
    *fbc = NULL;
    for (i = 1; i <= 3; i++) {
      requiredOverlayCriteria[0].value = i;
      vi = __glutDetermineVisualFromString(__glutDisplayString, treatAsSingle,
        requiredOverlayCriteria, numRequiredOverlayCriteria,
        requiredOverlayCriteriaMask, fbc);
      if (vi) {
        return vi;
      }
    }
    return NULL;
  } else {
    *visAlloced = True;
    *fbc = NULL;
    return __glutDetermineVisual(__glutDisplayMode,
      treatAsSingle, getOverlayVisualInfo);
  }
}

/* CENTRY */
void GLUTAPIENTRY
glutEstablishOverlay(void)
{
  GLUToverlay *overlay;
  GLUTwindow *window;
  XSetWindowAttributes wa;
  void *fbc;

  /* Register a routine to free an overlay with glut_win.c;
     this keeps glut_win.c from pulling in all of
     glut_overlay.c when no overlay functionality is used by
     the application. */
  __glutFreeOverlayFunc = __glutFreeOverlay;

  window = __glutCurrentWindow;

  /* Allow for an existant overlay to be re-established perhaps
     if you wanted a different display mode. */
  if (window->overlay) {
#if !defined(_WIN32)
    addStaleWindow(window, window->overlay->win);
#endif
    __glutFreeOverlay(window->overlay);
  }
  overlay = (GLUToverlay *) malloc(sizeof(GLUToverlay));
  if (!overlay)
    __glutFatalError("out of memory.");

  overlay->vis = determineOverlayVisual(&overlay->treatAsSingle,
    &overlay->visAlloced, &fbc);
  if (!overlay->vis) {
    __glutFatalError("lacks overlay support.");
  }
#if defined(GLX_VERSION_1_1) && defined(GLX_SGIX_fbconfig)
  if (fbc) {
    window->ctx = __glut_glXCreateContextWithConfigSGIX(__glutDisplay, fbc,
      GLX_RGBA_TYPE_SGIX, None, __glutTryDirect);
  } else
#endif
  {
    overlay->ctx = glXCreateContext(__glutDisplay, overlay->vis,
      None, __glutTryDirect);
  }
  if (!overlay->ctx) {
    __glutFatalError(
      "failed to create overlay OpenGL rendering context.");
  }
#if !defined(_WIN32)
  overlay->isDirect = glXIsDirect(__glutDisplay, overlay->ctx);
  if (__glutForceDirect) {
    if (!overlay->isDirect) {
      __glutFatalError("direct rendering not possible.");
    }
  }
#endif
  __glutSetupColormap(overlay->vis, &overlay->colormap, &overlay->cmap);
  overlay->transparentPixel = __glutGetTransparentPixel(__glutDisplay,
    overlay->vis);
  wa.colormap = overlay->cmap;
  wa.background_pixel = overlay->transparentPixel;
  wa.event_mask = window->eventMask & GLUT_OVERLAY_EVENT_FILTER_MASK;
  wa.border_pixel = 0;
#if defined(_WIN32)
  /* XXX Overlays not supported in Win32 yet. */
#else
  overlay->win = XCreateWindow(__glutDisplay,
    window->win,
    0, 0, window->width, window->height, 0,
    overlay->vis->depth, InputOutput, overlay->vis->visual,
    CWBackPixel | CWBorderPixel | CWEventMask | CWColormap,
    &wa);
#endif
  if (window->children) {
    /* Overlay window must be lowered below any GLUT
       subwindows. */
    XLowerWindow(__glutDisplay, overlay->win);
  }
  XMapWindow(__glutDisplay, overlay->win);
  overlay->shownState = 1;

  overlay->display = NULL;

  /* Make sure a reshape gets delivered. */
  window->forceReshape = True;

#if !defined(_WIN32)
  __glutPutOnWorkList(__glutToplevelOf(window), GLUT_COLORMAP_WORK);
#endif

  window->overlay = overlay;
  glutUseLayer(GLUT_OVERLAY);

  if (overlay->treatAsSingle) {
    glDrawBuffer(GL_FRONT);
    glReadBuffer(GL_FRONT);
  }
}

void GLUTAPIENTRY
glutRemoveOverlay(void)
{
  GLUTwindow *window = __glutCurrentWindow;
  GLUToverlay *overlay = __glutCurrentWindow->overlay;

  if (!window->overlay)
    return;

  /* If using overlay, switch to the normal layer. */
  if (window->renderWin == overlay->win) {
    glutUseLayer(GLUT_NORMAL);
  }
#if !defined(_WIN32)
  addStaleWindow(window, overlay->win);
#endif
  __glutFreeOverlay(overlay);
  window->overlay = NULL;
#if !defined(_WIN32)
  __glutPutOnWorkList(__glutToplevelOf(window), GLUT_COLORMAP_WORK);
#endif
}

void GLUTAPIENTRY
glutUseLayer(GLenum layer)
{
  GLUTwindow *window = __glutCurrentWindow;

  switch (layer) {
  case GLUT_NORMAL:
#ifdef _WIN32
    window->renderDc = window->hdc;
#endif
    window->renderWin = window->win;
    window->renderCtx = window->ctx;
    break;
  case GLUT_OVERLAY:
    /* Did you crash here?  Calling glutUseLayer(GLUT_OVERLAY)
       without an overlay established is erroneous.  Fix your
       code. */
#ifdef _WIN32
    window->renderDc = window->overlay->hdc;
#endif
    window->renderWin = window->overlay->win;
    window->renderCtx = window->overlay->ctx;
    break;
  default:
    __glutWarning("glutUseLayer: unknown layer, %d.", layer);
    break;
  }
  __glutSetWindow(window);
}

void GLUTAPIENTRY
glutPostOverlayRedisplay(void)
{
  __glutPostRedisplay(__glutCurrentWindow, GLUT_OVERLAY_REDISPLAY_WORK);
}

/* The advantage of this routine is that it saves the cost of a
   glutSetWindow call (entailing an expensive OpenGL context
   switch), particularly useful when multiple windows need
   redisplays posted at the same times. */
void GLUTAPIENTRY
glutPostWindowOverlayRedisplay(int win)
{
  __glutPostRedisplay(__glutWindowList[win - 1], GLUT_OVERLAY_REDISPLAY_WORK);
}

void GLUTAPIENTRY
glutOverlayDisplayFunc(GLUTdisplayCB displayFunc)
{
  if (!__glutCurrentWindow->overlay) {
    __glutWarning("glutOverlayDisplayFunc: window has no overlay established");
    return;
  }
  __glutCurrentWindow->overlay->display = displayFunc;
}

void GLUTAPIENTRY
glutHideOverlay(void)
{
  if (!__glutCurrentWindow->overlay) {
    __glutWarning("glutHideOverlay: window has no overlay established");
    return;
  }
  XUnmapWindow(__glutDisplay, __glutCurrentWindow->overlay->win);
  __glutCurrentWindow->overlay->shownState = 0;
}

void GLUTAPIENTRY
glutShowOverlay(void)
{
  if (!__glutCurrentWindow->overlay) {
    __glutWarning("glutShowOverlay: window has no overlay established");
    return;
  }
  XMapWindow(__glutDisplay, __glutCurrentWindow->overlay->win);
  __glutCurrentWindow->overlay->shownState = 1;
}

int GLUTAPIENTRY
glutLayerGet(GLenum param)
{
  switch (param) {
  case GLUT_OVERLAY_POSSIBLE:
    {
      XVisualInfo *vi;
      Bool dummy, visAlloced;
      void *fbc;

      vi = determineOverlayVisual(&dummy, &visAlloced, &fbc);
      if (vi) {
        if (visAlloced)
          XFree(vi);
        return 1;
      }
      return 0;
    }
  case GLUT_LAYER_IN_USE:
    return __glutCurrentWindow->renderWin != __glutCurrentWindow->win;
  case GLUT_HAS_OVERLAY:
    return __glutCurrentWindow->overlay != NULL;
  case GLUT_TRANSPARENT_INDEX:
    if (__glutCurrentWindow->overlay) {
      return __glutCurrentWindow->overlay->transparentPixel;
    } else {
      return -1;
    }
  case GLUT_NORMAL_DAMAGED:
    /* __glutWindowDamaged is used so the damage state within
       the window (or overlay belwo) can be cleared before
       calling a display callback so on return, the state does
       not have to be cleared (since upon return from the
       callback the window could be destroyed (or layer
       removed). */
    return (__glutCurrentWindow->workMask & GLUT_REPAIR_WORK)
      || __glutWindowDamaged;
  case GLUT_OVERLAY_DAMAGED:
    if (__glutCurrentWindow->overlay) {
      return (__glutCurrentWindow->workMask & GLUT_OVERLAY_REPAIR_WORK)
        || __glutWindowDamaged;
    } else {
      return -1;
    }
  default:
    __glutWarning("invalid glutLayerGet param: %d", param);
    return -1;
  }
}
/* ENDCENTRY */