我正在尝试使用Cocoa API创建一个OpenGL应用程序,到目前为止一切正常,除了一件事。调整主窗口大小时,GL上下文似乎无法正确更新。
这是用于设置窗口和渲染上下文的代码。
主窗口:
m_window = [[NSWindow alloc] initWithContentRect:window_rect
styleMask:( NSClosableWindowMask |
NSMiniaturizableWindowMask |
NSTitledWindowMask | NSResizableWindowMask )
backing:NSBackingStoreBuffered defer:YES];
window_title = [NSString stringWithCString:m_window_title->c_str()
encoding:NSUTF8StringEncoding];
window_color = [NSColor colorWithCalibratedRed:m_window_color->getRed()
green:m_window_color->getGreen()
blue:m_window_color->getBlue()
alpha:m_window_color->getAlpha()];
if ( m_centered )
{
[m_window center];
}
[m_window setTitle:window_title];
[m_window setBackgroundColor:window_color];
[m_window setOneShot:YES];
[m_window setOpaque:YES];
[m_window setDelegate:window_delegate];
[m_window setAcceptsMouseMovedEvents:YES];
window_title = [NSString stringWithCString:m_window_title->c_str()
encoding:NSUTF8StringEncoding];
window_color = [NSColor colorWithCalibratedRed:m_window_color->getRed()
green:m_window_color->getGreen()
blue:m_window_color->getBlue()
alpha:m_window_color->getAlpha()];
if ( m_centered )
{
[m_window center];
}
[m_window setTitle:window_title];
[m_window setBackgroundColor:window_color];
[m_window setOneShot:YES];
[m_window setOpaque:YES];
[m_window setDelegate:window_delegate];
[m_window setAcceptsMouseMovedEvents:YES];
OpenGL视图:
NSOpenGLPixelFormatAttribute attrs[] = {NSOpenGLPFADoubleBuffer, NSOpenGLPFAWindow, NULL};
pixel_format = [[NSOpenGLPixelFormat alloc] initWithAttributes:attrs];
m_view = [[NSOpenGLView alloc] initWithFrame:[m_window contentRectForFrameRect:[m_window frame]]
pixelFormat:pixel_format];
[pixel_format release];
GLint dim[2] = {GB_DEF_WINDOW_WIDTH, GB_DEF_WINDOW_HEIGHT};
CGLContextObj ctx = (CGLContextObj) [[m_view openGLContext] CGLContextObj];
CGLSetParameter(ctx, kCGLCPSurfaceBackingSize, dim);
CGLEnable (ctx, kCGLCESurfaceBackingSize);
[[m_view openGLContext] makeCurrentContext];
[m_window setContentView:m_view];
这应该可行,但是当调整窗口大小并更新OpenGL视图和视口后,后台缓冲区内容似乎无法正确重新调整。这有什么问题?
感谢您的回复。
答案 0 :(得分:0)
以下控制后台缓冲区的大小:
GLint dim[2] = {GB_DEF_WINDOW_WIDTH, GB_DEF_WINDOW_HEIGHT};
如何更改这些将影响后台缓冲区的大小。检查代码以设置这些值。当您调整大小时,假设您使窗口更薄,那么您将不得不更改宽度值,使其具有与窗口相同的宽高比。
请记住,后台缓冲区的内容不需要与显示它们的最终视图大小相同。如果存在差异,则缓冲区的内容将缩放以适合。如果纵横比不同,最终可能会出现奇怪的拉伸。