2002-08-27  Michael Natterer  <mitch@gimp.org>

	* app/base/curves.h: removed #defines and added enum CurvesType
	instead.

	* app/core/gimpchannel.c: use TRANSPARENT_OPACITY and
	OPAQUE_OPACITY instead of 0 and 255.

	* app/core/gimplayer.c (gimp_layer_create_mask): fixed inverse
	layer mask creation by setting GIMP_CHANNEL(mask)->bounds_known to
	FALSE correctly (fixes #90982). Also optimized mask creation
	by calling gimp_channel_all() and gimp_channel_clear() for
	white and black masks.