/* Copyright (C) 2000 artofcode LLC.  All rights reserved.
  
  This program is free software; you can redistribute it and/or modify it
  under the terms of the GNU General Public License as published by the
  Free Software Foundation; either version 2 of the License, or (at your
  option) any later version.

  This program is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  General Public License for more details.

  You should have received a copy of the GNU General Public License along
  with this program; if not, write to the Free Software Foundation, Inc.,
  59 Temple Place, Suite 330, Boston, MA, 02111-1307.

*/

/*$Id: gstrans.h,v 1.6.6.1.2.1 2003/01/17 00:49:03 giles Exp $ */
/* Transparency definitions and interface */

#ifndef gstrans_INCLUDED
#  define gstrans_INCLUDED

#include "gstparam.h"

/* Access transparency-related graphics state elements. */
int gs_setblendmode(P2(gs_state *, gs_blend_mode_t));
gs_blend_mode_t gs_currentblendmode(P1(const gs_state *));
int gs_setopacityalpha(P2(gs_state *, floatp));
float gs_currentopacityalpha(P1(const gs_state *));
int gs_setshapealpha(P2(gs_state *, floatp));
float gs_currentshapealpha(P1(const gs_state *));
int gs_settextknockout(P2(gs_state *, bool));
bool gs_currenttextknockout(P1(const gs_state *));

/*
 * Manage transparency group and mask rendering.  Eventually these will be
 * driver procedures, taking dev + pis instead of pgs.
 */

gs_transparency_state_type_t
    gs_current_transparency_type(P1(const gs_state *pgs));

/*
 * We have to abbreviate the procedure name because procedure names are
 * only unique to 23 characters on VMS.
 */
void gs_trans_group_params_init(P1(gs_transparency_group_params_t *ptgp));

int gs_begin_transparency_group(P3(gs_state *pgs,
				   const gs_transparency_group_params_t *ptgp,
				   const gs_rect *pbbox));

int gs_end_transparency_group(P1(gs_state *pgs));

void gs_trans_mask_params_init(P2(gs_transparency_mask_params_t *ptmp,
				  gs_transparency_mask_subtype_t subtype));

int gs_begin_transparency_mask(P3(gs_state *pgs,
				  const gs_transparency_mask_params_t *ptmp,
				  const gs_rect *pbbox));

int gs_end_transparency_mask(P2(gs_state *pgs,
				gs_transparency_channel_selector_t csel));

int gs_init_transparency_mask(P2(gs_state *pgs,
				 gs_transparency_channel_selector_t csel));

int gs_discard_transparency_layer(P1(gs_state *pgs));

#endif /* gstrans_INCLUDED */