<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=Content-Type content="text/html; charset=us-ascii"> <META content="MSHTML 6.00.6000.16640" name=GENERATOR></HEAD> <BODY> <DIV><SPAN class=741044422-23042008><FONT face=Arial size=2>While profiling a test app I did with Cairo (mostly scaled up/down and rotated blitting), I noticed a LOT of time is spent fetching and storing pixels in Pixman. I had a look and implemented a small optimization that substantially reduces the number of fetching calls needed. This optimization works well especially in the cases of scaled up blitting and bilinear filtering, as we'll be often requesting the same pixels many times in a row. There's no point in fetching them again.</FONT></SPAN></DIV> <DIV><SPAN class=741044422-23042008><FONT face=Arial size=2>In my test app, blitting an image 11 times ranging linearly between scales of 1.0 to 3.0 (while rotating 10 degrees each time), this patch goes from 18.6 million calls of fbfetch down to 10 million.</FONT></SPAN></DIV> <DIV><SPAN class=741044422-23042008><FONT face=Arial size=2></FONT></SPAN> </DIV> <DIV><SPAN class=741044422-23042008><FONT face=Arial size=2>I'm attaching here my patch, along with some benchmark results. <SPAN class=741044422-23042008><FONT face=Arial size=2>The performance gains go up to about 3X.</FONT></SPAN></FONT></SPAN></DIV> <DIV><SPAN class=741044422-23042008><FONT face=Arial size=2><SPAN class=741044422-23042008></SPAN></FONT></SPAN> </DIV> <DIV><SPAN class=741044422-23042008><FONT face=Arial size=2><SPAN class=741044422-23042008>I'm still looking into further optimizing fetching/storing calls.</SPAN></FONT></SPAN></DIV> <DIV><SPAN class=741044422-23042008><FONT face=Arial size=2></FONT></SPAN> </DIV> <DIV><SPAN class=741044422-23042008><FONT face=Arial size=2>Best,</FONT></SPAN></DIV> <DIV><SPAN class=741044422-23042008><FONT face=Arial size=2>Antoine</FONT></SPAN></DIV></BODY></HTML>