2008-05-10  Michael Natterer  <mitch@gimp.org>

	Applied modified patch from Alexia Death which adds velocity
	support to paint tools in the spirit of the pressure support we
	already have. Fixes bug #529431.

	* app/display/gimpdisplayshell-coords.c
	(gimp_display_shell_eval_event): tweak velocity calculation to
	work in screen coordinates.

	* app/paint/gimppaintoptions.[ch]: add velocity options in the
	same way as there are pressure options. Add utility functions
	which return dynamic opatity and dynamic rate according to the the
	option's settings and some GimpCoords' pressure and velocity.

	* app/tools/gimppaintoptions-gui.c: add GUI for the velocity
	options.

	* app/paint/gimpbrushcore.h: remove PRESSURE_SCALE define, it's
	now in gimppaintoptions.h.

	* app/paint/gimpbrushcore.c (gimp_brush_core_interpolate):
	inerpolate velocity too.

	(gimp_brush_core_calc_brush_scale): take velocity into account.

	(gimp_brush_core_get_brush_mask): always pressurize the mask in
	the GIMP_BRUSH_PRESSURE because there always is velocity (unlike
	pressure which is only there on tablets).

	* app/paint/gimpairbrush.c
	* app/paint/gimpclone.c
	* app/paint/gimpconvolve.c
	* app/paint/gimpdodgeburn.c
	* app/paint/gimperaser.c
	* app/paint/gimpheal.c
	* app/paint/gimppaintbrush.c
	* app/paint/gimpsmudge.c: get opacity and rate from the new paint
	options utility functions which take both pressure and velocity
	into account.

	* app/paint/gimppaintbrush.c: take velocity into account when
	calculating the gradient color offset.

	* app/paint/gimpairbrush.c: do some additional fiddling with
	velocity in the asynchronous airbrush timeout.

	* app/paint/gimpairbrushoptions.c: override the velocity-size
	property and have it default to FALSE.


svn path=/trunk/; revision=25604