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/*
(c) Copyright 2001-2009 The world wide DirectFB Open Source Community (directfb.org)
(c) Copyright 2000-2004 Convergence (integrated media) GmbH
All rights reserved.
Written by Denis Oliver Kropp <dok@directfb.org>,
Andreas Hundt <andi@fischlustig.de>,
Sven Neumann <neo@directfb.org>,
Ville Syrjälä <syrjala@sci.fi> and
Claudio Ciccani <klan@users.sf.net>.
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the
Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.
*/
#ifndef __GFX__CLIP_H__
#define __GFX__CLIP_H__
#include <directfb.h>
typedef enum {
DFEF_NONE = 0x00000000,
DFEF_LEFT = 0x00000001,
DFEF_RIGHT = 0x00000002,
DFEF_TOP = 0x00000004,
DFEF_BOTTOM = 0x00000008,
DFEF_ALL = 0x0000000F
} DFBEdgeFlags;
/*
* Clips the line to the clipping region.
* Returns DFB_TRUE if at least one pixel of the line resides in the region.
*/
DFBBoolean dfb_clip_line( const DFBRegion *clip, DFBRegion *line );
/*
* Clips the rectangle to the clipping region.
* Returns true if there was an intersection with the clipping region.
*/
DFBBoolean dfb_clip_rectangle( const DFBRegion *clip, DFBRectangle *rect );
/*
* Clips the rectangle to the clipping region.
* Returns a flag for each edge that wasn't cut off.
*/
DFBEdgeFlags dfb_clip_edges( const DFBRegion *clip, DFBRectangle *rect );
static inline DFBBoolean
dfb_clip_needed( const DFBRegion *clip, DFBRectangle *rect )
{
return ((clip->x1 > rect->x) ||
(clip->y1 > rect->y) ||
(clip->x2 < rect->x + rect->w - 1) ||
(clip->y2 < rect->y + rect->h - 1));
}
/*
* Simple check if triangle lies outside the clipping region.
* Returns true if the triangle may be visible within the region.
*/
DFBBoolean dfb_clip_triangle_precheck( const DFBRegion *clip,
const DFBTriangle *tri );
/*
* Clips the triangle to the clipping region.
* Returns true if the triangle if visible within the region.
* The vertices of the polygon resulting from intersection are returned in buf.
* The number of vertices is at least 3.
*/
DFBBoolean dfb_clip_triangle( const DFBRegion *clip,
const DFBTriangle *tri,
DFBPoint buf[6],
int *num );
/*
* Simple check if requested blitting lies outside of the clipping region.
* Returns true if blitting may need to be performed.
*/
static inline DFBBoolean
dfb_clip_blit_precheck( const DFBRegion *clip,
int w, int h, int dx, int dy )
{
if (w < 1 || h < 1 ||
(clip->x1 >= dx + w) ||
(clip->x2 < dx) ||
(clip->y1 >= dy + h) ||
(clip->y2 < dy))
return DFB_FALSE;
return DFB_TRUE;
}
/*
* Clips the blitting request to the clipping region.
* This includes adjustment of source AND destination coordinates.
*/
void dfb_clip_blit( const DFBRegion *clip,
DFBRectangle *srect, int *dx, int *dy );
/*
* Clips the stretch blit request to the clipping region.
* This includes adjustment of source AND destination coordinates
* based on the scaling factor.
*/
void dfb_clip_stretchblit( const DFBRegion *clip,
DFBRectangle *srect,
DFBRectangle *drect );
#endif
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