Description:
[This is mentioned in the dev blog, but I wasn't able to find a bug report for it. Apologies if it is a duplicate.]
The redraw strategy used by the software renderer is so slow and distracting as to make the program practically unusable. The program spends almost all its time erasing and redrawing the modeling canvas.
Some of the redraws I noticed include:
- pull down menus - it should use saveunders when available or a clip region to redraw when not
- scrolling canvas - it should only draw the newly exposed piece of canvas
- mouse over edge - it should only redraw the highlighted edge
- mouse over node - it's currently doing two complete window redraws (one going in, one coming out), when the rendering of the node doesn't change at all. No redraws should be done
How to repeat:
Perform any of the operations listed above on a system where the tool has decided to use the software rendering pipe.
Suggested fix:
Use save unders for menus. Use clip regions to redraw only the necessary pieces of the canvas.
Additionally, for something which has such a serious impact, you should provide a way for the user to override your automatic guess as to whether harware or software rendering is better. A three choice option of : 1) best available, 2) hardware, 3) software, would be appropriate here.
