netsurf/riscos/thumbnail.c
James Bursa cff65dfddf [project @ 2004-02-26 17:23:02 by bursa]
Use save area when redirecting to sprite.

svn path=/import/netsurf/; revision=570
2004-02-26 17:23:02 +00:00

92 lines
2.4 KiB
C

/*
* This file is part of NetSurf, http://netsurf.sourceforge.net/
* Licensed under the GNU General Public License,
* http://www.opensource.org/licenses/gpl-license
* Copyright 2004 James Bursa <bursa@users.sourceforge.net>
*/
/** \file
* Page thumbnail creation (implementation).
*
* Thumbnails are created by redirecting output to a sprite and rendering the
* page at a small scale.
*/
#include "oslib/colourtrans.h"
#include "oslib/osspriteop.h"
#include "netsurf/content/content.h"
#include "netsurf/riscos/thumbnail.h"
#include "netsurf/utils/log.h"
/**
* Create a thumbnail of a page.
*
* \param content content structure to thumbnail
* \param area sprite area containing thumbnail sprite
* \param sprite pointer to sprite
* \param width sprite width / pixels
* \param height sprite height / pixels
*
* The thumbnail is rendered in the given sprite.
*/
void thumbnail_create(struct content *content, osspriteop_area *area,
osspriteop_header *sprite, int width, int height)
{
int size;
int context1, context2, context3;
float scale;
osspriteop_save_area *save_area;
os_error *error;
scale = (float) width / (float) content->width;
/* allocate save area */
error = xosspriteop_read_save_area_size(osspriteop_PTR, area,
(osspriteop_id) sprite, &size);
if (error) {
LOG(("xosspriteop_read_save_area_size failed: 0x%x: %s",
error->errnum, error->errmess));
return;
}
save_area = malloc((unsigned) size);
if (!save_area) {
LOG(("malloc failed"));
return;
}
save_area->a[0] = 0;
/* switch output to sprite */
error = xosspriteop_switch_output_to_sprite(osspriteop_PTR, area,
(osspriteop_id) sprite, save_area,
0, &context1, &context2, &context3);
if (error) {
LOG(("xosspriteop_switch_output_to_sprite failed: 0x%x: %s",
error->errnum, error->errmess));
return;
}
/* clear background to white */
colourtrans_set_gcol(os_COLOUR_WHITE, colourtrans_SET_BG,
os_ACTION_OVERWRITE, 0);
os_clg();
/* render content */
content_redraw(content, 0, height * 2, width * 2, height * 2,
0, 0, width * 2, height * 2, scale);
/* switch output back to screen */
error = xosspriteop_switch_output_to_sprite(osspriteop_PTR,
(osspriteop_area *) context1,
(osspriteop_id) context2,
(osspriteop_save_area *) context3,
0, 0, 0, 0);
if (error) {
LOG(("xosspriteop_switch_output_to_sprite failed: %s",
error->errmess));
}
free(save_area);
}