When I enable a programmable renderer, the ofRect function works differently

When I change to a programmable renderer using

ofSetCurrentRenderer(ofGLProgrammableRenderer::TYPE);

ofRect seems to behave differently with the same numbers. I previously painted a fragment shader on a rectangle that took these values: 0, 0, ofGetWindowWidth(), ofGetWindowHeight(). This would previously fill the entire window, but now it only fills the top right corner. Any idea what is happening here?

Edit: For some reason only ofRect(-1.0, -1.0, 2.0, 2.0) fills the screen…