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/*
* Copyright © 2007 Chris Wilson
*
* Permission to use, copy, modify, distribute, and sell this software
* and its documentation for any purpose is hereby granted without
* fee, provided that the above copyright notice appear in all copies
* and that both that copyright notice and this permission notice
* appear in supporting documentation, and that the name of
* Chris Wilson not be used in advertising or publicity pertaining to
* distribution of the software without specific, written prior
* permission. Chris Wilson makes no representations about the
* suitability of this software for any purpose. It is provided "as
* is" without express or implied warranty.
*
* CHRIS WILSON DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
* SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS, IN NO EVENT SHALL CHRIS WILSON BE LIABLE FOR ANY SPECIAL,
* INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
* RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR
* IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* Author: Chris Wilson <chris@chris-wilson.co.uk>
*
* Inspiration (and path!) taken from
* http://labs.trolltech.com/blogs/2007/08/31/rasterizing-dragons/
*/
#include "cairo-perf.h"
#ifndef MIN
#define MIN(a,b) (((a) < (b)) ? (a) : (b))
#endif
#ifndef MAX
#define MAX(a,b) (((a) > (b)) ? (a) : (b))
#endif
static inline int
next_pot (int v)
{
v--;
v |= v >> 1;
v |= v >> 2;
v |= v >> 4;
v |= v >> 8;
v |= v >> 16;
v++;
return v;
}
static cairo_bool_t
direction (int i)
{
int pivot, np2;
if (i < 2)
return TRUE;
np2 = next_pot (i + 1);
if (np2 == i + 1)
return TRUE;
pivot = np2 / 2 - 1;
return ! direction (2 * pivot - i);
}
static void
path (cairo_t *cr, int step, int dir, int iterations)
{
double dx, dy;
int i;
switch (dir) {
case 0: dx = step; dy = 0; break;
case 1: dx = -step; dy = 0; break;
case 2: dx = 0; dy = step; break;
case 3: dx = 0; dy = -step; break;
}
for (i = 0; i < iterations; i++) {
cairo_rel_line_to (cr, dx, dy);
if (direction (i)) {
double t = dx;
dx = dy;
dy = -t;
} else {
double t = dx;
dx = -dy;
dy = t;
}
}
}
static cairo_perf_ticks_t
do_dragon (cairo_t *cr, int width, int height)
{
cairo_pattern_t *pattern;
double cx, cy, r;
cx = cy = .5 * MAX (width, height);
r = .5 * MIN (width, height);
cairo_perf_timer_start ();
pattern = cairo_pattern_create_radial (cx, cy, 0., cx, cy, r);
cairo_pattern_add_color_stop_rgb (pattern, 0., .0, .0, .0);
cairo_pattern_add_color_stop_rgb (pattern, 0.25, .5, .4, .4);
cairo_pattern_add_color_stop_rgb (pattern, .5, .8, .8, .9);
cairo_pattern_add_color_stop_rgb (pattern, 1., .9, .9, 1.);
cairo_set_source (cr, pattern);
cairo_pattern_destroy (pattern);
cairo_paint (cr);
cairo_set_line_cap (cr, CAIRO_LINE_CAP_ROUND);
cairo_set_line_join (cr, CAIRO_LINE_JOIN_ROUND);
cairo_set_line_width (cr, 4.);
cairo_move_to (cr, cx, cy);
path (cr, 12, 0, 2048);
pattern = cairo_pattern_create_radial (cx, cy, 0., cx, cy, r);
cairo_pattern_add_color_stop_rgb (pattern, 0., 1., 1., 1.);
cairo_pattern_add_color_stop_rgb (pattern, 1., 0., 0., 0.);
cairo_set_source (cr, pattern);
cairo_pattern_destroy (pattern);
cairo_stroke(cr);
cairo_move_to (cr, cx, cy);
path (cr, 12, 1, 2048);
pattern = cairo_pattern_create_radial (cx, cy, 0., cx, cy, r);
cairo_pattern_add_color_stop_rgb (pattern, 1., 1., 1., 0.);
cairo_pattern_add_color_stop_rgb (pattern, 0., 1., 0., 0.);
cairo_set_source (cr, pattern);
cairo_pattern_destroy (pattern);
cairo_stroke(cr);
cairo_move_to (cr, cx, cy);
path (cr, 12, 2, 2048);
pattern = cairo_pattern_create_radial (cx, cy, 0., cx, cy, r);
cairo_pattern_add_color_stop_rgb (pattern, 1., 0., 1., 1.);
cairo_pattern_add_color_stop_rgb (pattern, 0., 0., 1., 0.);
cairo_set_source (cr, pattern);
cairo_pattern_destroy (pattern);
cairo_stroke(cr);
cairo_move_to (cr, cx, cy);
path (cr, 12, 3, 2048);
pattern = cairo_pattern_create_radial (cx, cy, 0., cx, cy, r);
cairo_pattern_add_color_stop_rgb (pattern, 1., 1., 0., 1.);
cairo_pattern_add_color_stop_rgb (pattern, 0., 0., 0., 1.);
cairo_set_source (cr, pattern);
cairo_pattern_destroy (pattern);
cairo_stroke(cr);
cairo_perf_timer_stop ();
return cairo_perf_timer_elapsed ();
}
static cairo_perf_ticks_t
do_dragon_solid (cairo_t *cr, int width, int height)
{
double cx, cy, r;
cx = cy = .5 * MAX (width, height);
r = .5 * MIN (width, height);
cairo_perf_timer_start ();
cairo_set_source_rgb (cr, 0, 0, 0);
cairo_paint (cr);
cairo_set_line_width (cr, 4.);
cairo_move_to (cr, cx, cy);
path (cr, 12, 0, 2048);
cairo_set_source_rgb (cr, 1, 0, 0);
cairo_stroke(cr);
cairo_move_to (cr, cx, cy);
path (cr, 12, 1, 2048);
cairo_set_source_rgb (cr, 0, 1, 0);
cairo_stroke(cr);
cairo_move_to (cr, cx, cy);
path (cr, 12, 2, 2048);
cairo_set_source_rgb (cr, 0, 0, 1);
cairo_stroke(cr);
cairo_move_to (cr, cx, cy);
path (cr, 12, 3, 2048);
cairo_set_source_rgb (cr, 1, 1, 1);
cairo_stroke(cr);
cairo_perf_timer_stop ();
return cairo_perf_timer_elapsed ();
}
void
dragon (cairo_perf_t *perf, cairo_t *cr, int width, int height)
{
if (! cairo_perf_can_run (perf, "dragon"))
return;
cairo_perf_run (perf, "dragon-solid", do_dragon_solid);
cairo_perf_run (perf, "dragon", do_dragon);
}
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