Mercurial > sdl-ios-xcode
view README.Watcom @ 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 | 8c72321542f6 |
children |
line wrap: on
line source
Using SDL 1.3 under Windows with the OpenWatcom compiler ==================================================== Prerequisites ------------- I have done the port under Windows XP Professional with SP2 installed. Windows 2000 should also be working. I'm not so sure about ancient Windows NT, since only DirectX 3 is available there. Building should be possible, but running the compiled applications will probalbly fail with SDL_VIDEODRIVER=directx. The windib driver should work, though. To compile and use the SDL with Open Watcom you will need the following: - Open Watcom compiler. I used version 1.8. The environment variables PATH, WATCOM and INCLUDE need to be set appropriately - please consult the OpenWatcom documentation and instructions given during the installation of the compiler. My setup looks like this in owvars.bat: set WATCOM=C:\dev\ow18 set INCLUDE=%WATCOM%\h;%WATCOM%\h\nt set PATH=%PATH%;%WATCOM%\binnt;%WATCOM%\binw - A recent DirectX SDK. The library needs D3d9.h so at leat the directx 9 sdk is to be used. I used DirectX 10 SDK from August 2009 taken directly from the microsoft site. - The SDL 1.3 sources from Subversion - The file Watcom-Win32.zip (now available in Subversion) Building the Library -------------------- 1) In the SDL base directory extract the archive Watcom-Win32.zip. This creates a subdirectory named 'watcom'. 2) The makefile expects the environment variable DXDIR to be set to the base directory of a DirectX SDK. I have tried the August 2009 DirectX SDK from Microsoft You can also edit the makefile directly and hard code your path to the SDK on your system. I have this in my setup: set DXDIR=..\dx10 3) Enter the watcom directory and run wmake sdl 4) All tests from the test directory are working and can be built by running wmake tests Notes: The makefile offers some options to tweak the way the library is built. You have at your disposal the option to build a static (default) library, or a DLL (with tgt=dll). You can also choose whether to build a Release (default) or a Debug version (with build=debug) of the tests and library. Please consult the usage comment at the top of the makefile for usage instructions. If you specify a test target (i.e. 'wmake tests' for all tests, or selected targets like 'wmake testgl testvidinfo testoverlay2'), the tests are always freshly compiled and linked. This is done to minimise hassle when switching between library versions (static vs. DLL), because they require subtly different options. Also, the test executables are put directly into the test directory, so they can find their data files. The clean target of the makefile removes the test executables and the SDL.dll file from the test directory. To use the library in your own projects with Open Watcom, you can use the way the tests are built as base of your own build environment. The library can also be built with the stack calling convention of the compiler (-6s instead of -6r). Test applications ----------------- $FixME: which test works ? which one compiles ? I've tried to make all tests work. The following table gives an overview of the current status. Testname Status ~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ checkkeys + graywin + loopwave + testalpha + testbitmap + testdyngl + testerror + testfile + testgamma + testgl + testhread + testiconv - (all failed) testkeys + testlock + testoverlay + (needs 'set SDL_VIDEODRIVER=directx') testoverlay2 + (needs 'set SDL_VIDEODRIVER=directx') testpalette + testplatform + testsem + testsprite + testtimer + testver + testvidinfo + testwin ? (fading doesn't seem right) testwm + torturethread + testcdrom + testjoystick not tested threadwin + testcursor + TODO ---- There is room for further improvement: - Test joystick functionality. - Investigate fading issue in 'testwin' test. - Fix the UTF-8 support. - Adapt the makefile/object file list to support more target systems - Use "#pragma aux" syntax for the CPU info functions. Questions and Comments ---------------------- Please direct any questions or comments to me: ow_sdl [at] digitalfantasy [dot] it The original porting to the open watcom compiler was made by Marc Peter <mailto:macpete@gmx.de> Happy Coding! Daniele Forghieri