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view README.Porting @ 5053:b5b42be9333c
Fixed bug #1026
Vittorio Giovara 2010-07-16 19:09:28 PDT
i was reading SDL_renderer_gles and i noticed that every time we there
is some gl call the gl state is modified with a couple of
glEnableClientState()/glDisableClientState.
While this is completely fine for desktops systems, this is a major
performace kill on mobile devices, right where opengles is
implemented.
Normal practice in this case is to update the glstate once, keep it
always the same and disable/enable other states only in very special
occasions.
On the web there's plenty of documentation (on the top of my head
http://developer.apple.com/iphone/library/documentation/3DDrawing/Conceptual/OpenGLES_ProgrammingGuide/Performance/Performance.html#//apple_ref/doc/uid/TP40008793-CH105-SW5
) and i personally tried this.
I modified my code and got a 10 fps boost, then modified SDL_render_gles and
shifted from 40 fps to 50 fps alone -- considering that i started from ~30fps i
got an 80% performance increase with this technique.
I have attached a dif of my changes, hope that it will be included in
mainstream.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Wed, 19 Jan 2011 23:56:16 -0800 |
parents | 103760c3a5dc |
children |
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* Porting To A New Platform The first thing you have to do when porting to a new platform, is look at include/SDL_platform.h and create an entry there for your operating system. The standard format is __PLATFORM__, where PLATFORM is the name of the OS. Ideally SDL_platform.h will be able to auto-detect the system it's building on based on C preprocessor symbols. There are two basic ways of building SDL at the moment: 1. The "UNIX" way: ./configure; make; make install If you have a GNUish system, then you might try this. Edit configure.in, take a look at the large section labelled: "Set up the configuration based on the target platform!" Add a section for your platform, and then re-run autogen.sh and build! 2. Using an IDE: If you're using an IDE or other non-configure build system, you'll probably want to create a custom SDL_config.h for your platform. Edit SDL_config.h, add a section for your platform, and create a custom SDL_config_{platform}.h, based on SDL_config.h.minimal and SDL_config.h.in Add the top level include directory to the header search path, and then add the following sources to the project: src/*.c src/audio/*.c src/cdrom/*.c src/cpuinfo/*.c src/events/*.c src/file/*.c src/joystick/*.c src/stdlib/*.c src/thread/*.c src/timer/*.c src/video/*.c src/audio/disk/*.c src/audio/dummy/*.c src/video/dummy/*.c src/joystick/dummy/*.c src/cdrom/dummy/*.c src/thread/generic/*.c src/timer/dummy/*.c src/loadso/dummy/*.c Once you have a working library without any drivers, you can go back to each of the major subsystems and start implementing drivers for your platform. If you have any questions, don't hesitate to ask on the SDL mailing list: http://www.libsdl.org/mailing-list.php Enjoy! Sam Lantinga (slouken@libsdl.org)