[sdl_omap.git] / README.OMAP

(some) OMAP hardware support for SDL
by notaz (notasas@gmail.com)


About
-----

This is a quick SDL driver to make use of some OMAP features, namely double
buffering and hardware scaler.

The backstory of this is that SDL on Pandora console was suffering from tearing
and stuttering problems because SDL default x11 driver doesn't work that well
there. Almost 6 months have passed after pandora's release, no improved
SDL versions appeared (not blaming anyone here, pandora's availability was low
and there where were several SDL improvement in the works though). This
encouraged me to create this quick version until something better appears
(if ever).

Although this was created for pandora, there is nothing preventing this to work
on other OMAP platforms as well (well, nothing intentional at least).


Usage / environment
-------------------

To enable this driver, SDL_VIDEODRIVER environment variable must be set to
"omapdss". It can be set by calling setenv() in the code, but it's better to
just set it in launcher script so that it can be changed easily without
recompiling as needed:
---
#!/bin/sh
export SDL_VIDEODRIVER=omapdss
./your_program_here
---

Other environment variables:

SDL_OMAP_LAYER_SIZE:
  Output layer size. Regardless what you set with SDL_SetVideoMode(), output
  will be scaled to this size using hardware. Valid values:
    "WxH", for example "640x480"
    "fullscreen" for to cover whole screen.

SDL_OMAP_VSYNC:
  Enables waiting for vertical sync on SDL_Flip() calls.
  Set to "1" to enable, "0" to disable.

SDL_OMAP_DEFAULT_MODE:
  If the app doesn't specify resolution in SDL_SetVideoMode(), then use this.
  Should be specified in "WxH" format, for example "640x480".


Config file
-----------

Optionally a file named "omapsdl.cfg" can be created in the game's working
directory. It has lower priority than environment variables, and has these
options (only when omapdss driver is active):

# same as SDL_OMAP_VSYNC
force_vsync = 1/0

# can be used to bind a key to SDL keysym, good for quick ports.
# Example:
# bind ev_home = sdlk_space
bind ev_<evdev_key> = <sdl_key>


Source
------

Available at git://notaz.gp2x.de/~notaz/sdl_omap.git
Commit	Line	Data
50339c93	1	(some) OMAP hardware support for SDL
	2	by notaz (notasas@gmail.com)
	3
	4
	5	About
	6	-----
	7
	8	This is a quick SDL driver to make use of some OMAP features, namely double
	9	buffering and hardware scaler.
	10
	11	The backstory of this is that SDL on Pandora console was suffering from tearing
	12	and stuttering problems because SDL default x11 driver doesn't work that well
	13	there. Almost 6 months have passed after pandora's release, no improved
	14	SDL versions appeared (not blaming anyone here, pandora's availability was low
	15	and there where were several SDL improvement in the works though). This
	16	encouraged me to create this quick version until something better appears
	17	(if ever).
	18
	19	Although this was created for pandora, there is nothing preventing this to work
	20	on other OMAP platforms as well (well, nothing intentional at least).
	21
	22
	23	Usage / environment
	24	-------------------
	25
	26	To enable this driver, SDL_VIDEODRIVER environment variable must be set to
	27	"omapdss". It can be set by calling setenv() in the code, but it's better to
	28	just set it in launcher script so that it can be changed easily without
	29	recompiling as needed:
	30	---
	31	#!/bin/sh
	32	export SDL_VIDEODRIVER=omapdss
	33	./your_program_here
	34	---
	35
	36	Other environment variables:
5d957fa5	37
50339c93	38	SDL_OMAP_LAYER_SIZE:
	39	Output layer size. Regardless what you set with SDL_SetVideoMode(), output
	40	will be scaled to this size using hardware. Valid values:
	41	"WxH", for example "640x480"
	42	"fullscreen" for to cover whole screen.
5d957fa5	43
50339c93	44	SDL_OMAP_VSYNC:
5d957fa5	45	Enables waiting for vertical sync on SDL_Flip() calls.
50339c93	46	Set to "1" to enable, "0" to disable.
50339c93	47
5d957fa5	48	SDL_OMAP_DEFAULT_MODE:
	49	If the app doesn't specify resolution in SDL_SetVideoMode(), then use this.
	50	Should be specified in "WxH" format, for example "640x480".
	51
50339c93	52
	53	Config file
	54	-----------
	55
	56	Optionally a file named "omapsdl.cfg" can be created in the game's working
	57	directory. It has lower priority than environment variables, and has these
	58	options (only when omapdss driver is active):
	59
	60	# same as SDL_OMAP_VSYNC
	61	force_vsync = 1/0
	62
	63	# can be used to bind a key to SDL keysym, good for quick ports.
	64	# Example:
	65	# bind ev_home = sdlk_space
	66	bind ev_<evdev_key> = <sdl_key>
	67
7b66578c	68
	69	Source
	70	------
	71
	72	Available at git://notaz.gp2x.de/~notaz/sdl_omap.git
	73