[Marble-devel] New scanline access method

[Carlos Licea]

List,
	Reading through the planet I found this post:
	http://zecke.blogspot.com/2009/11/collecting-hints-to-increase.html
	When I checked the repository I found:
	http://gitorious.org/qt-performance/qt-performance/blobs/master/performance-
guide/qimage.xml
	I immediately remembered that we use QImage::scanLine method in the ScanLine 
approach and sat down to try the new approach.
	Here you have the patch.

	Short story: doesn't seem to work.
	Long story: I didn't do any very deep analysis just ran marble with the 
option --timedemo and here are the results (they are not averages of multiple 
runs, I just ran them a couple of times and wrote the value once when I saw 
that I didn't have any gains):

				Old approach			New approach
Spherical			45414ms"=4.40383 fps"	58491ms"=3.41933 fps"
Equirectangular	58673ms"=3.40872 fps"	61583ms"=3.24765 fps"
Mercator			66459ms"=3.00937 fps" 	71495ms"=2.7974 fps"

	It's really thrilling that we not only we are not improving, but that we are 
having even worse performance.

Carlos
PS: I couldn't CC the author of the post. I wasn't able to find his email 
address (not that I really, really tried).
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