diff --git a/docs/README-touch.md b/docs/README-touch.md index e76e2d396..da781253d 100644 --- a/docs/README-touch.md +++ b/docs/README-touch.md @@ -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. -This returns a SDL_Finger*, or NULL if the finger does not exist, or has been removed. +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.