我需要在一个Qt5项目中执行多重采样,但我不确定如何使用QOpenGLFrameBufferObject来执行FSAA。据我所搜寻,没有关于如何做到这一点的示例,并且文档只提到:“如果您想使用启用了多重采样的帧缓冲对象作为纹理,则需要首先使用QOpenGLContext::blitFramebuffer()将其从帧缓冲对象复制到普通帧缓冲对象。”我的代码目前看起来像这样:
//Enable FSAA for better output
int vp[4];
glGetIntegerv(GL_VIEWPORT, vp);
if(m_lpFBO == NULL)
{
//MultiSampling set to 4 now
QOpenGLFramebufferObjectFormat format;
format.setAttachment(QOpenGLFramebufferObject::CombinedDepthStencil);
format.setMipmap(true);
format.setSamples(4);
format.setTextureTarget(GL_TEXTURE_2D);
format.setInternalTextureFormat(GL_RGBA32F_ARB);
//Create the FBO
m_lpFBO = new QOpenGLFramebufferObject(vp[2], vp[3], format);
m_lpFBOSurface = new QGLFramebufferObjectSurface(m_lpFBO);
}
QRect rc(0, 0, vp[2], vp[3]);
QGLSubsurface sub(lpPainter->currentSurface(), rc);
m_lpFBO->bind();
sub.setFramebufferObject(m_lpFBO);
lpPainter->pushSurface(&sub);
//Draw as usual
.
.
.
lpPainter->popSurface();
//Now Copy
QOpenGLFramebufferObject::blitFramebuffer(lpPainter->currentSurface()->framebufferObject(), rc, m_lpFBO, rc);