How can I use QGLFramebufferObject for render-to-texture without using QPainter
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Hi all,
I'm new to QT. I want to combine my game engine with QT for multi-platform use.
The other part of my graphic was done by OpenGL only, I don't want to let QPainter to render on screen or on render targets. I also want to include "qgl.h" only without depending on another gl lib. I found glGenFramebuffers is not defined although my target machines should have this feature.
So how can I render to the FBO created by *QGLFramebufferObject * without using QPainter? The only example that I found relatively was http://qt-project.org/doc/qt-4.8/opengl-framebufferobject-glwidget-cpp.html which used QPainter.
Another problem that I met was I detected memory leaks in using QImage to load pngs and turning it to GL format. My code is like
@
QImage qimg;
qimg.loadFromData((BYTE*)data, _size);
QImage qimg_gl = QGLWidget::convertToGLFormat(qimg);
if (qimg_gl.isNull())
{
return NULL;
}
glGenTextures(1, &pTex);
if (pTex) {
glBindTexture(GL_TEXTURE_2D, pTex);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, qimg_gl.width(), qimg_gl.height(), 0, GL_RGBA, GL_UNSIGNED_BYTE, qimg_gl.bits());
}
@
Later I called glDeleteTextures for releasing. However, I tracked something created by QT caused memory leak. Do I need to call somthing like qimg_gl.Free to avoid leaking? My BYTE*data was deleted correctedly.
