AWT.GetDrawingSurface做什么?

时间:2014-06-20 10:56:01

标签: java c++ java-native-interface vtk jawt

我正在进行一个需要在Java和JavaFX上使用vtk的项目。为了给VTK提供可以绘制的正确画布,我想知道GetDrawingSurface()函数在下面的代码中做了什么。 awt是jawt库中jawt.h中描述的JAWT对象。

这是为了重写Java类,为C ++提供正确的画布。

extern "C" JNIEXPORT jint  JNICALL
Java_vtk_vtkPanel_RenderCreate(JNIEnv *env, jobject canvas, jobject id0)
{
#if defined(WIN32_JAWT_LOCK_HACK)
  int hash;
  WJLH_HASH_FUNC(env, canvas, hash);
  WJLH_lock_map[hash] = 0;
#endif

  JAWT awt;
  JAWT_DrawingSurface* ds;
  JAWT_DrawingSurfaceInfo* dsi;
  jint lock;

  // get the render window pointer
  vtkRenderWindow *temp0;
  temp0 = (vtkRenderWindow *)(vtkJavaGetPointerFromObject(env,id0));

  /* Get the AWT */
  awt.version = JAWT_VERSION_1_3;
  if (JAWT_GetAWT(env, &awt) == JNI_FALSE)
    {
#ifndef VTK_JAVA_DEBUG
    printf("AWT Not found\n");
#endif
    return 1;
    }

  /* Get the drawing surface */
  ds = awt.GetDrawingSurface(env, canvas);
  if (ds == NULL)
    {
#ifndef VTK_JAVA_DEBUG
    printf("NULL drawing surface\n");
#endif
    return 1;
    }

  /* Lock the drawing surface */
  lock = ds->Lock(ds);
  if((lock & JAWT_LOCK_ERROR) != 0)
    {
#ifndef VTK_JAVA_DEBUG
    printf("Error locking surface\n");
#endif
    awt.FreeDrawingSurface(ds);
    return 1;
    }

  /* Get the drawing surface info */
  dsi = ds->GetDrawingSurfaceInfo(ds);
  if (dsi == NULL)
    {
    printf("Error getting surface info\n");
    ds->Unlock(ds);
    awt.FreeDrawingSurface(ds);
    return 1;
    }

// Here is the win32 drawing code
#if defined(_WIN32) || defined(WIN32)
  temp0->Finalize();
  JAWT_Win32DrawingSurfaceInfo* dsi_win;
  dsi_win = (JAWT_Win32DrawingSurfaceInfo*)dsi->platformInfo;
  temp0->SetWindowId((void *)dsi_win->hwnd);
  temp0->SetDisplayId((void *)dsi_win->hdc);
  // also set parent id to avoid border sizes being added
  temp0->SetParentId((void *)dsi_win->hdc);
// use mac code
#elif defined(__APPLE__)
  JAWT_MacOSXDrawingSurfaceInfo* dsi_mac;
  dsi_mac = (JAWT_MacOSXDrawingSurfaceInfo*)dsi->platformInfo;
  temp0->SetWindowId(dsi_mac->cocoaViewRef);
// otherwise use X11 code
#else
  JAWT_X11DrawingSurfaceInfo* dsi_x11;
  dsi_x11 = (JAWT_X11DrawingSurfaceInfo*)dsi->platformInfo;
  temp0->SetDisplayId((void *)dsi_x11->display);
  temp0->SetWindowId((void *)dsi_x11->drawable);
  temp0->SetParentId((void *)dsi_x11->display);
#endif

  /* Free the drawing surface info */
  ds->FreeDrawingSurfaceInfo(dsi);

  /* Unlock the drawing surface */
  ds->Unlock(ds);

  /* Free the drawing surface */
  awt.FreeDrawingSurface(ds);

#if defined(WIN32_JAWT_LOCK_HACK)
  if (WJLH_init_check == 0)
    {
    WJLH_init_check = 1;
    }
  WJLH_lock_map[hash] = 1;
#endif
  return 0;
}

1 个答案:

答案 0 :(得分:0)

好吧,我自己发现它正在返回关于系统上窗口管理器使用的信息。

它使用java的getPeer函数来获取正确的信息并将其提供给C代码。因此,不可能给出我想要绘制的位置,因为javadoc清楚地告诉它它是特定于计算机的并且无法重写。

希望最后一个VTK版本(6.1.0)使用vtkJoGLPanelComponent为JavaFX中的VTK提供了一个新选项。我认为它应该是轻量级的,因为另一个选项vtkJoGLCanvasComponent根本不起作用。