view README.PicoGUI @ 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 706de3956894
children
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 ========================
  Using SDL with PicoGUI
 ========================

- Originally contributed by Micah Dowty <micahjd@users.sourceforge.net>

PicoGUI is a scalable GUI system with a unique architecture, primarily focused
on scalability to various embedded systems. You can find more information
including a FAQ at http://picogui.org

To use the patch:

  1. When compiling, add the "--enable-video-picogui" switch to ./configure

  2. When running your program, ensure that the picogui driver for SDL
     is in use by setting the SDL_VIDEODRIVER environment variable 
     to "picogui".

  3. The program must also be linked to the C client library for PicoGUI
     (libpgui.so). If the program is being compiled with a patched SDL 
     installed this should be done automatically. If you want to use an
     existing binary with PicoGUI, you can set the LD_PRELOAD environment
     variable to the path of your libpgui.so file.

Capabilities:

  So far only basic functionality is provided on true color (linear16/24/32)
  devices. Accessing a memory mapped bitmap, updating the display, and handling
  mouse/keyboard input. This functionality has been tested with several
  applications, including mplayer, Xine, sldroids, and Abuse.

TODO list:

  - YUV overlays will be helpful for watching video on set top boxes or other
    embedded devices that have some graphics acceleration hardware

  - Account for rotated bitmap storage in pgserver

  - Support for hiding or changing the cursor

  - The display should be centered when the SDL application is smaller
    than the PicoGUI panel

  - Fullscreen or any other special modes

  - Support for indexed and grayscale modes

  - Probably much more...

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