On Tue, 11 Nov 2008 14:50:46 +0000 Matthew Allum <[EMAIL PROTECTED]> babbled:
> Hi; > > On Tue, 2008-11-11 at 06:25 -0800, Ian Lawrence wrote: > > > > Others are looking at performance issues too > > http://lists.o-hand.com/clutter/1209.html > > and it seems loading images into GL textures is an expensive process > > which can only realistically be achieved with extra hardware and/or > > some future caching system . This cost needs to be taken into > > consideration when other solutions like EFL already exist and have > > been proven to work well in this space. > > Uuhhh - if your saying you take a hit in moving image data from system > to texture memory then yes of course you will on certain hardware > setups. How much this hit is and how relevant that is to the real world > is debatable *but* this is a dumb argument anyway Clutter on GPU will > outperform many 100x in terms of rendering operations (and more) > compared to software only options. If it did not, GPU's would not exist. hmmm i would have to say "many 100x" is going to be a major leap. we actually have benchmarks. gl vs software. sure.some things are a lot faster in gl (5-10x). others.. software beats gl. in fact the averags fps i get on a normal desktop (2x core core2 3ghz) vs an nvidia 8600gt - evas. gl vs software_x11 - over all tests in expedite (which is a fair few) gl gets an average of about 1100fps (from memory) and software is pushing 800fps or so... got real numbers. that's from memory - but on my current laptop. nvidia 8600m (mobile) vs core2 due 2.3ghz mobile: 868fps vs 671fps (for all tests) let me quote some "interesting results". 1. alpha blending a whole bunch of non-scaled images (1:1) gl ONLY managed to be 4x faster than software... not 100's of times. 2. at BEST when doing "smooth scaling" (that means for GL GL_LINEAR vs full super/sub sampling in software (which is much higher quality especially on down-scale) gl manages at BEST to be 30x faster than software. different algorithms here so software is at a major disadvantage due to its higher quality. 3. apples vs apples... scaling an image with "GL_NEAREST" in software and gl... gl is 5.8times faster. 4. software is actually FASTER for alpha blending a whole bunch of rectangles - 25% faster. gl uses just a quad. software is at an advantage - it's smarter adn can calculate deltas better 5. gl shos overhead on having to upload ARGB pixels textures - software manages to do the argb data change test about 25% faster than gl (that includes also drawing the image to the screen after upload of new data). i'm just saying this above as i believe that there are bogus facts being floated about (efl starves your cpu - incorrect. it uses just as little/much as clutter would.. if you use the gl engine or any other accelerated back end - xrender (an the acceleration is working) etc.) and the numbers on "gl is 100x faster" i would say is entirely bogus. i am pitting a very very very fast gpu against a very fast laptop cpu. and the cpu is doing a stellar job of keeping up... considering. and both engines can be optimised - i know just what i could do to improve them, and i don't see that your numbers will change so drastically if i did it on both ends. :) -- ------------- Codito, ergo sum - "I code, therefore I am" -------------- The Rasterman (Carsten Haitzler) [EMAIL PROTECTED] _______________________________________________ Moblin dev Mailing List [email protected] To manage or unsubscribe from this mailing list visit: https://lists.moblin.org/mailman/listinfo/dev or your user account on http://moblin.org once logged in. For more information on the Moblin Developer Mailing lists visit: http://moblin.org/community/mailing-lists
