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copied!<p>Extending leemes' answer, here is a solution which can also handle multisample framebuffer objects.</p> <p>First, if you want to draw on a QGLWidget, you can simply use the OpenGL commands leemes suggested in his answer. Note that there is a ready-to-use <code>drawTexture()</code> command available, which simplifies this code to the following:</p> <pre><code>void Widget::drawFBO(QPainter &painter, QGLFramebufferObject &fbo, QRect target) { painter.beginNativePainting(); drawTexture(target, fbo.texture()); painter.endNativePainting(); } </code></pre> <p>To draw multisample FBOs, you can convert them into non-multisample ones using <a href="http://qt-project.org/doc/qt-5.0/qglframebufferobject.html#blitFramebuffer"><code>QGLFramebufferObject::blitFramebuffer</code></a> (Note that not every hardware / driver combination supports this feature!):</p> <pre><code>if(fbo.format().samples() > 1) { QGLFramebufferObject texture(fbo.size()); // the non-multisampled fbo QGLFramebufferObject::blitFramebuffer( &texture, QRect(0, 0, fbo.width(), fbo.height()), &fbo, QRect(0, 0, fbo.width(), fbo.height())); drawTexture(targetRect, texture.texture()); } else drawTexture(targetRect, fbo.texture()); </code></pre> <p>However, as far as I know, you can't draw using OpenGL commands on a non-OpenGL context. For this, you first need to convert the framebuffer to a (software) image, like a QImage using <code>fbo.toImage()</code> and draw this using your QPainter instead of the fbo directly.</p>

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