Zoom Performance

Holding down the Ctrl key at the same time as rolling the mouse wheel will speed up the operation by only drawing a subset of the line primitives. The quality level can be controlled in Tools > Preferences > Miscellaneous form; a greater value will draw fewer lines and thereby increase performance. The Delay is the amount of time after the user stopped rolling the mouse until a normal repaint with full quality is made. This also applies to Middle Button Drag (panning).