Fixed information in touch README and changed identifiers so doxygen links them.

This commit is contained in:
Philipp Wiesemann 2016-07-27 20:47:31 +02:00
parent 3853f7cd3a
commit 456901150c

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@ -42,14 +42,14 @@ Same as SDL_FINGERDOWN.
===========================================================================
Functions
===========================================================================
SDL provides the ability to access the underlying Finger structures.
SDL provides the ability to access the underlying SDL_Finger structures.
These structures should _never_ be modified.
The following functions are included from SDL_touch.h
To get a SDL_TouchID call SDL_GetTouchDevice(index).
To get a SDL_TouchID call SDL_GetTouchDevice(int index).
This returns a SDL_TouchID.
IMPORTANT: If the touch has been removed, or there is no touch with the given ID, SDL_GetTouchID will return 0. Be sure to check for this!
IMPORTANT: If the touch has been removed, or there is no touch with the given index, SDL_GetTouchDevice() will return 0. Be sure to check for this!
The number of touch devices can be queried with SDL_GetNumTouchDevices().
@ -64,13 +64,13 @@ The most common reason to access SDL_Finger is to query the fingers outside the
To get a SDL_Finger, call SDL_GetTouchFinger(touchID,index), where touchID is a SDL_TouchID, and index is the requested finger.
To get a SDL_Finger, call SDL_GetTouchFinger(SDL_TouchID touchID, int index), where touchID is a SDL_TouchID, and index is the requested finger.
This returns a SDL_Finger *, or NULL if the finger does not exist, or has been removed.
A 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 SDL_FINGERUP event is polled.
As a result, be very careful to check for NULL return values.
A SDL_Finger has the following fields:
* x,y,pressure:
* x, y:
The current coordinates of the touch.
* pressure:
The pressure of the touch.