The effect works only correctly with the OpenGL backend (Graphic and FPS text label). When using XRender, no text label is drawn. Reproducible: Always
Yes that's to be expected as the text is only drawn in OpenGL. I think I added the number in the QPainter compositor (for next version) and that should make it possible to add the number also for XRender.
Git commit 61c5a801ba75d51ee17e53e13250d9151c7923e3 by Thomas Lübking. Committed on 04/08/2013 at 12:50. Pushed by luebking into branch 'KDE/4.11'. support fps counter text on xrender FIXED-IN: 4.11 REVIEW: 111878 M +25 -15 kwin/effects/showfps/showfps.cpp M +1 -1 kwin/effects/showfps/showfps.h http://commits.kde.org/kde-workspace/61c5a801ba75d51ee17e53e13250d9151c7923e3