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Fixed bug #859 CREATE_SUBDIRS helps a lot if browsing HTML documentation in a file browser. ALWAYS_DETAILED_SEC makes sure everything has at least the automatic documentation like function prototype and source references. STRIP_FROM_PATH allows you to include only the relevant portions of the files' paths, cleaning up both the file list and directory tree, though you need to change the path listed here to match wherever you put SDL. ALIASES avoids some warnings generated by C:\source\svn.libsdl.org\trunk\SDL\src\joystick\darwin\10.3.9-FIX\IOHIDLib.h. It seems Apple uses a few commands which are not normally supported by Doxygen. BUILTIN_STL_SUPPORT adds support for parsing code which makes use of the standard template library. There isn't a lot of C++ in SDL (some in bwindow at least), but this still seems like a good idea. TYPEDEF_HIDES_STRUCT means that for code like this: typedef struct A {int B;} C; C is documented as a structure containing B instead of a typedef mapped to A. EXTRACT_ALL, EXTRACT_PRIVATE, EXTRACT_STATIC, EXTRACT_LOCAL_METHODS, EXTRACT_ANON_NSPACES and INTERNAL_DOCS make sure that _everything_ is documented. CASE_SENSE_NAMES = NO avoids potential conflicts when building documentation on case insensitive file systems like NTFS and FAT32. WARN_NO_PARAMDOC lets you know when you have documented some, but not all, of the parameters of a function. This is useful when you're working on adding such documentation since it makes partially documented functions easier to spot. WARN_LOGFILE writes warnings to a seperate file instead of mixing them in with stdout. When not running in quiet mode, these warnings can be hard to spot without this flag. I added *.h.in and *.h.default to FILE_PATTERNS to generate documentation for config.h.in and config.h.default. RECURSIVE tells doxygen to look not only in the input directory, but also in subfolders. EXCLUDE avoids documenting things like test programs, examples and templates which need to be documented separately. I've used EXCLUDE_PATTERNS to exclude non-source subdirectories that often find their way into source folders (such as obj or .svn). EXAMPLE_PATH lists directories doxygen will search to find included example code. So far, SDL doesn't really use this feature, but I've listed some likely locations. SOURCE_BROWSER adds syntax highlighted source code to the HTML output. USE_HTAGS is nice, but not available on Windows. INLINE_SOURCES adds the body of a function to it's documentation so you can quickly see exactly what it does. ALPHABETICAL_INDEX generates an alphabetical list of all structures, functions, etc., which makes it much easier to find what you're looking for. IGNORE_PREFIX skips the SDL_ prefix when deciding which index page to place an item on so you don't have everything show up under "S". HTML_DYNAMIC_SECTIONS hides the includes/included by diagrams by default and adds JavaScript to allow the user to show and hide them by clicking a link. ENUM_VALUES_PER_LINE = 1 makes enums easier to read by placing each value on it's own line. GENERATE_TREEVIEW produces a two frame index page with a navigation tree on the left. I have LaTeX and man pages turned off to speed up doxygen, you may want to turn them back on yourself. I added _WIN32=1 to PREDEFINED to cause SDL to output documentation related to Win32 builds of SDL. Normally, doxygen gets confused since there are multiple definitions for various structures and formats that vary by platform. Without this doxygen can produce broken documentation or, if you're lucky, output documentation only for the dummy drivers, which isn't very useful. You need to pick a platform. GENERATE_TAGFILE produces a file which can be used to link other doxygen documentation to the SDL documentation. CLASS_DIAGRAMS turns on class diagrams even when dot is not available. HAVE_DOT tells doxygen to try to use dot to generate diagrams. TEMPLATE_RELATIONS and INCLUDE_GRAPH add additional diagrams to the documentation. DOT_MULTI_TARGETS speeds up dot. OUTPUT_DIRECTORY, INPUT and other paths reflect the fact that this Doxyfile is intended to process src as well as include and is being run from a separate subdirectory. Doxygen produces several temporary files while it's running and if interrupted, can leave those files behind. It's easier to clean up if there aren't a hundred or so files in the same folder. I typically run doxygen in SDL/doxy and set the output directory to '.'. Since doxygen puts it's output in subfolders by type, this keeps things pretty well organised. You could use '../doc' instead and get the same results.
author Sam Lantinga <slouken@libsdl.org>
date Fri, 21 Jan 2011 12:57:01 -0800
parents 2ede56a19f2f
children
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===========================================================================
System Specific Notes
===========================================================================
Linux:
The linux touch system is currently based off event streams, and proc/bus/devices. The active user must be given permissions to read /dev/input/TOUCHDEVICE, where TOUCHDEVICE is the event stream for your device. Currently only Wacom tablets are supported. If you have an unsupported tablet contact me at jim.tla+sdl_touch@gmail.com and I will help you get support for it.

Mac: 
The Mac and Iphone API's are pretty. If your touch device supports them then you'll be fine. If it doesn't, then there isn't much we can do.

iPhone: 
Works out of box.

Windows:
Unfortunately there is no windows support as of yet. Support for Windows 7 is planned, but we currently have no way to test. If you have a Windows 7 WM_TOUCH supported device, and are willing to help test please contact me at jim.tla+sdl_touch@gmail.com

===========================================================================
Events
===========================================================================
SDL_FINGERDOWN:
Sent when a finger (or stylus) is placed on a touch device.
Fields:
event.tfinger.touchId  - the Id of the touch device.
event.tfinger.fingerId - the Id of the finger which just went down.
event.tfinger.x        - the x coordinate of the touch (0..touch.xres)
event.tfinger.y        - the y coordinate of the touch (0..touch.yres)
event.tfinger.pressure - the pressure of the touch (0..touch.pressureres)

SDL_FINGERMOTION:
Sent when a finger (or stylus) is moved on the touch device.
Fields:
Same as FINGERDOWN but with additional:
event.tfginer.dx       - change in x coordinate during this motion event.
event.tfginer.dy       - change in y coordinate during this motion event.

SDL_FINGERMOTION:
Sent when a finger (or stylus) is lifted from the touch device.
Fields:
Same as FINGERDOWN.


===========================================================================
Functions
===========================================================================
SDL provides the ability to access the underlying Touch and Finger structures.
These structures should _never_ be modified.

The following functions are included from SDL_Touch.h

To get a SDL_Touch device call SDL_GetTouch(touchId). 
This returns an SDL_Touch*. 
IMPORTANT: If the touch has been removed, or there is no touch with the given ID, SDL_GetTouch will return null. Be sure to check for this!

An SDL_Touch has the following fields:
>xres,yres,pressures:
	The resolution at which x,y, and pressure values are reported. Currently these will always be equal to 2^15, but this may not always be the case. 

>pressure_max, pressure_min, x_max, x_min, y_max, y_min
	Which give, respectively, the maximum and minumum values that the touch digitizer can return for pressure, x coordiniate, and y coordinate AS REPORTED BY THE OPERATING SYSTEM.
On Mac/iPhone systems _max will always be 0, and _min will always be 1. 

>native_xres,native_yres,native_pressureres:
	The native resolution of the touch device AS REPORTED BY THE OPERATING SYSTEM.
On Mac/iPhone systems these will always be 1.

>num_fingers:
	The number of fingers currently down on the device.

>fingers:
	An array of pointers to the fingers which are on the device.


The most common reason to access a touch device is to normalize inputs. This would be accomplished by code like the following:

      SDL_Touch* inTouch = SDL_GetTouch(event.tfinger.touchId);
      if(inTouch == NULL) continue; //The touch has been removed

      float x = ((float)event.tfinger.x)/inTouch->xres;
      float y = ((float)event.tfinger.y)/inTouch->yres;



To get an SDL_Finger, call SDL_GetFinger(touch,fingerId), where touch is a pointer to an SDL_Touch device, and fingerId is the id of the requested finger.
This returns an SDL_Finger*, or null if the finger does not exist, or has been removed.
An SDL_Finger is guaranteed to be persistent for the duration of a touch, but it will be de-allocated as soon as the finger is removed. This occurs when the SDL_FINGERUP event is _added_ to the event queue, and thus _before_ the FINGERUP event is polled. 
As a result, be very careful to check for null return values.

An SDL_Finger has the following fields:
>x,y,pressure:
	The current coordinates of the touch.
>xdelta,ydelta: 
	The change in position resulting from the last finger motion.
>last_x, last_y, last_pressure:
	 The previous coordinates of the touch.

===========================================================================
Notes
===========================================================================
For a complete example see test/testgesture.c

Please direct questions/comments to:
   jim.tla+sdl_touch@gmail.com