DWM

http://stackoverflow.com/questions/9786218/drawing-in-window-while-resizing-leaves-unpainted-border
http://stackoverflow.com/questions/10615272/opengl-flickering-damaged-with-window-resize-and-dwm-active
http://stackoverflow.com/questions/21154185/synchronization-between-dwm-and-direct3d-window

Desktop Compositionを有効にすると screen tearing が減るけれど、描画が遅延する。ウィンドウのリサイズ時に気になるなぁ。。