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/*
* Copyright 2009 Vincent Sanders <vince@simtec.co.uk>
*
* This file is part of libnsfb, http://www.netsurf-browser.org/
* Licenced under the MIT License,
* http://www.opensource.org/licenses/mit-license.php
*
* This is the exported interface for the libnsfb graphics library.
*/
#ifndef _LIBNSFB_PLOT_UTIL_H
#define _LIBNSFB_PLOT_UTIL_H 1
/* alpha blend two pixels together */
static inline nsfb_colour_t
nsfb_plot_ablend(nsfb_colour_t pixel, nsfb_colour_t scrpixel)
{
int opacity = pixel >> 24;
int transp = 0x100 - opacity;
uint32_t rb, g;
rb = ((pixel & 0xFF00FF) * opacity +
(scrpixel & 0xFF00FF) * transp) >> 8;
g = ((pixel & 0x00FF00) * opacity +
(scrpixel & 0x00FF00) * transp) >> 8;
return (rb & 0xFF00FF) | (g & 0xFF00);
}
bool nsfb_plot_clip(const nsfb_bbox_t * restrict clip, nsfb_bbox_t * restrict rect);
bool nsfb_plot_clip_ctx(nsfb_t *nsfb, nsfb_bbox_t * restrict rect);
bool nsfb_plot_clip_line(const nsfb_bbox_t * restrict clip, nsfb_bbox_t * restrict line);
bool nsfb_plot_clip_line_ctx(nsfb_t *nsfb, nsfb_bbox_t * restrict line);
/** Obtain a bounding box which is the superset of two source boxes.
*
*/
bool nsfb_plot_add_rect(const nsfb_bbox_t *box1, const nsfb_bbox_t *box2, nsfb_bbox_t *result);
/** Find if two boxes intersect. */
bool nsfb_plot_bbox_intersect(const nsfb_bbox_t *box1, const nsfb_bbox_t *box2);
#endif /* _LIBNSFB_PLOT_UTIL_H */
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