Mercurial > sdl-ios-xcode
view README.Epoc @ 1259:36f24cdfcda7
te: Thu, 17 Apr 2003 11:25:26 -0700
From: "Jim"
Subject: [SDL] Frame buffer patches...
Would seem that GCC 3.2.2 promotes all signed values to unsigned if any single vlaue is unsigned in an expression...
for instance when calculating an elo touch position....evertyhign is an (int) except for cach_vinfo.xres which is unsigned. THerefore if y
ou reverse the SDL_ELO_MIN_X and SDL_ELO_MAX_X values the resulging negative value pegs the expression to it's max. Attached it the accumu
lated patch to typecast the unsigned values to (int)
- *dx = (cache_vinfo.xres - (cache_vinfo.xres * (input_x - ELO_MIN_X)) / width);
+ *dx = ((int)cache_vinfo.xres - ((int)cache_vinfo.xres * (input_x - ELO_MIN_X)) / width);
and also to provide quite failure to operations which have the screen currently locked...
The touch screen I'm using the original values were exactly opposite of any position I touched on the screen - evaluating the math the expr
ession SHOULD have handled reversing the min and max values - and after casting the unsigned .xres and .yres to a signed int - worked well.
..
Jim
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Tue, 24 Jan 2006 06:36:43 +0000 |
| parents | 74a8f672f2f8 |
| children |
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============================================================================== Using the Simple DirectMedia Layer with EPOC/SymbianOS 6.0 ============================================================================== ============================================================================== I. Building the Simple DirectMedia Layer libraries: You can get Symbian SDK from: http://www.symbian.com. First create "Epoc" directory under SDL main directory and unpack EpocBuildFiles.zip in it. To build the librarys goto "epoc" directory and type: bldmake bldfiles abld makefile vc6 (for creating Microsoft Visual C++ makefiles) abld build wins udeb (building for wins emulator) abld build armi urel (building for real device) ============================================================================== II. Building the Simple DirectMedia Layer programs: Building SDL test programs is easy once you have built the libraries: abld test build wins udeb abld test build armi urel Supported real screen resolutions 320 x 200 x 8 bit 320 x 200 x 12 bit 640 x 200 x 8 bit 640 x 200 x 12 bit Supported "emulated" screen resolutions 640 x 400 x 8 bit 640 x 400 x 12 bit 640 x 480 x 8 bit 640 x 480 x 12 bit "Emulated" resolutions are implemented by by shrinking the screen vertically i.e. only every second scanline is drawn. This is mainly ment to be used for testing quick ports of programs. Using faked resolutions is a waste of memory and cpu power! ============================================================================== III. Running test programs Copy executable to the device and run it from the File manager. The Esc key quits demo programs. In Crystal, Exe programs do not appear in task list nor in Extras :-(. Test programs are tested in Nokia 9210 Communicator. Special keys used in SDL: The Caps lock key enables or disables the virtual cursor. Function keys are mapped as follows: F1=chr+q, F2=chr+w,..., F8=chr+i, F9=chr+a,..., F12=chr+d. ============================================================================== IV. Enjoy! :) If you have a project you'd like me to know about, or want to ask questions, go ahead and join the SDL developer's mailing list by sending e-mail to: sdl-request@libsdl.org and put "subscribe" into the subject of the message. Or alternatively you can use the web interface: http://www.libsdl.org/mailman/listinfo/sdl You can find more info about Epoc version of SDL from Hannu Viitala's homepage http://www.mbnet.fi/~haviital ==============================================================================