view README.NanoX @ 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 26dafefeebb2
children
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  =================================================================
  Patch version 0.9 of SDL(Simple DirectMedia Layer) for Nano-X API
  =================================================================
  
  Authors: Hsieh-Fu Tsai, clare@setabox.com
           Greg Haerr, greg@censoft.com

  This patch is against SDL version 1.2.4.
  It enhances previous patch 0.8 by providing direct framebuffer
  access as well as dynamic hardware pixel type support, not
  requiring a compile-time option setting for different framebuffer
  modes.
  Tested against Microwindows version 0.89pre9.

  Older Microwindows versions
  ===========================
  If running on a version older than Microwindows 0.89pre9,
  the following items might need to be patched in Microwindows.

  1. Patch src/nanox/client.c::GrClose()
  It fixes the client side GrClose(). In the original version, 
  GrOpen() can only be called once. When the GrOpen() is called at 
  the second time, the program will terminate. In order to prevent
  this situation, we need to insert "nxSocket = -1" after 
  "close(nxSocket)" in GrClose(). If you do not have this problem,
  you may skip this step. 

  2. Patch src/nanox/clientfb.c to return absolute x,y coordinates
  when using GrGetWindowFBInfo().  Copy the version 0.89pre9
  of src/nanox/clientfb.c to your system, or configure
  using --disable-nanox-direct-fb.

  =============
  Quick Install 
  =============

  1. ./configure --disable-video-x11 --disable-video-fbcon \ 
       --enable-video-nanox \ 
       --with-nanox-pixel-type=[rgb/0888/888/565/555/332/pal] 
  2. make clean 
  3. make 
  4. make install (as root) 

  ============
  Nitty-gritty 
  ============

  --enable-nanox-direct-fb       Use direct framebuffer access
  --enable-nanox-debug           Show debug messages 
  --enable-nanox-share-memory    Use shared-memory to speed up 

  When running multi-threaded applications using SDL, such
  as SMPEG, set THREADSAFE=Y in Microwindows' config file,
  to enable GrXXX() system call critical section support.

  =============================================
  Some programs can be used to test this patch. 
  =============================================

  1. http://www.cs.berkeley.edu/~weimer/atris (a tetris-like game) 
  2. http://www.libsdl.org/projects/newvox/
  3. http://www.libsdl.org/projects/xflame/
  4. http://www.libsdl.org/projects/optimum/ 
  5. http://www.gnugeneration.com/software/loop/ 
  6: http://www.lokigames.com/development/smpeg.php3 (SMPEG version 0.4.4)

  =========
  Todo List 
  =========

  1. Create hardware surface
  2. Create YUVOverlay on hardware
  3. Use OpenGL
  4. Gamma correction
  5. Hide/Change mouse pointer
  6. Better window movement control with direct fb access
  7. Palette handling in 8bpp could be improved

  =====================
  Supporting Institutes
  =====================
  
  Many thanks to go to Setabox Co., Ltd. and CML (Communication and
  Multimedia Laboratory, http://www.cmlab.csie.ntu.edu.tw/) in the 
  Department of Computer Science and Information Engineering of 
  National Taiwan University for supporting this porting project.
  
  Century Embedded Technologies (http://embedded.censoft.com)
  for this patch.

  ===================
  Contact Information
  ===================

  Welcome to give me any suggestion and to report bugs.
  My e-mail address : clare@setabox.com or niky@cmlab.csie.ntu.edu.tw
                      or greg@censoft.com