bulia byak wrote:
On 1/5/07, Jasper van de Gronde <th.v.d.gronde@...528...> wrote:
BTW, enlarging the stripe size has a very nice effect on rendering time, when I first tried rendering redblur.svg (attached to the initial post) with the IIR patch it took slightly less than two minutes, with the entire image as one stripe it takes about ten seconds! (at 1600x1200)
If by "stripe size" you mean the size of pixblock, then I already increased it some time ago from 64K to 256K for normal mode and to 1M for outline mode:
No, I mean the size of the stripes used by sp_png_write_rgba_striped (in helper/png-write.cpp). Currently hard-coded to a maximum of 64 pixel rows, regardless of their width btw (even though sp_export_png_file can specify a larger stripe height). What I would like to propose is: - Remove the hard-coded limit from sp_png_write_rgba_striped (the h = min(height-r,64) line). - Using the size of the pixblock allocated instead of a maximum row count. - Making the maximum stripe size larger and/or configurable, as it is incredibly small at the moment and it can apparently make quite a difference in performance (although I expect, or at least hope, it will usually not be as dramatic as in the example above).
The only downside to this that I can see at the moment is that it might make exporting less responsive, but that would just be one reason to make it configurable. (Of course it would be great if it would be possible to get the same performance without increasing the stripe size.)