README.QNX
changeset 3092 cad1aefa2ed9
parent 3083 0bc41e0361d3
child 3099 82e60908fab1
     1.1 --- a/README.QNX	Sun Mar 15 15:50:18 2009 +0000
     1.2 +++ b/README.QNX	Tue Mar 17 03:24:22 2009 +0000
     1.3 @@ -1,4 +1,57 @@
     1.4  README.QNX by Mike Gorchak <mike@malva.ua>, <lestat@i.com.ua>
     1.5 -Last changed at 02 Mar 2009.
     1.6 +Last changed at 10 Mar 2009.
     1.7  
     1.8  QNX Photon and GF drivers are under construction. Please be patient.
     1.9 +
    1.10 +---------------------
    1.11 + -- SDL GF driver --
    1.12 +---------------------
    1.13 +
    1.14 +Here is an additional information about SDL GF driver:
    1.15 + * 0. Introduction.
    1.16 + * 1. Environment variables which SDL GF driver supports.
    1.17 + * 2. Custom video modes.
    1.18 + * 3. Limitations.
    1.19 +
    1.20 +0. Introduction.
    1.21 +
    1.22 +   SDL GF driver is a layer between SDL and QNX Graphics Framework (GF). Hardware
    1.23 +accelerated features which SDL could support depends on real hardware capabilities.
    1.24 +
    1.25 +1. Environment variables which GF driver supports.
    1.26 +
    1.27 +   GF driver supports the following environment variables for QNX GF specific
    1.28 +customization options:
    1.29 +   a) SDL_VIDEO_GF_REFRESH_RATE - refresh rate of video output in Hz. Without
    1.30 +      this environment variable declaration SDL controls refresh rate of your
    1.31 +      display. If this enironment variable is set to 0, SDL will control refresh
    1.32 +      rate of display, otherwise value of SDL_VIDEO_GF_REFRESH_RATE is used for
    1.33 +      all screen resolutions as refresh rate. This example will set 60Hz refresh
    1.34 +      rate as refresh rate for all graphics modes:
    1.35 +
    1.36 +      export SDL_VIDEO_GF_REFRESH_RATE=60
    1.37 +
    1.38 +2. Custom video modes.
    1.39 +
    1.40 +   Since most QNX graphics drivers supports GENERIC video modes, i.e. you could
    1.41 +specify any horizontal and vertical resolution and any refresh rate, SDL GF
    1.42 +driver uses its own fullscreen modes list, which could be incomplete. You could
    1.43 +add any custom video mode, which your QNX graphics driver supports by editing
    1.44 +file ./src/video/qnxgf/SDL_qnxgf.c. Custom graphics mode definition looks like
    1.45 +
    1.46 +   {0, 1024, 640, 60, NULL},   /* 1024x640 mode is 60Hz only               */
    1.47 +
    1.48 +You must specify horizontal resolution as second parameter, vertical resolution
    1.49 +as third parameter and refresh rate as fourth parameter. Please leave first and
    1.50 +last parameters as 0 and NULL. Then please send me your changes to e-mail address
    1.51 +which is specified in the header of this document.
    1.52 +
    1.53 +3. Limitations.
    1.54 +
    1.55 +   There are few limitations while using SDL GF driver:
    1.56 +
    1.57 +   a) Since GF driver supports fullscreen modes only, when you are not specifing
    1.58 +SDL_WINDOW_FULLSCREEN flag, an SDL GF driver will try to find the fullscreen
    1.59 +graphics mode which corresponds to SDL window size. Refresh rate will be the
    1.60 +lowest available, if SDL_VIDEO_GF_REFRESH_RATE environment variable is not set.
    1.61 +