cairo/test/a1-image-sample.c

/*
 * Copyright © 2008 Red Hat, Inc.
 *
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use, copy,
 * modify, merge, publish, distribute, sublicense, and/or sell copies
 * of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 * Author: Carl D. Worth <cworth@cworth.org>
 */

#include "cairo-test.h"

static cairo_test_draw_function_t draw;

#define POINTS	10
#define STEP	(1.0 / POINTS)
#define PAD	1
#define WIDTH	(PAD + POINTS * 2 + PAD)
#define HEIGHT	(WIDTH)

cairo_test_t test = {
    "a1-image-sample",
    "Test sample position when drawing images with FILTER_NEAREST",
    WIDTH, HEIGHT,
    draw
};

/* A single, black pixel */
static const uint32_t black_pixel = 0xff000000;

static cairo_test_status_t
draw (cairo_t *cr, int width, int height)
{
    int i, j;
    cairo_surface_t *surface;

    surface = cairo_image_surface_create_for_data ((unsigned char *) &black_pixel,
						   CAIRO_FORMAT_ARGB32,
						   1, 1, 4);

    /* Fill background white */
    cairo_set_source_rgb (cr, 1, 1, 1);
    cairo_paint (cr);

    /* Draw in black */
    cairo_set_source_rgb (cr, 0, 0, 0);

    cairo_translate (cr, PAD, PAD);
    cairo_set_antialias (cr, CAIRO_ANTIALIAS_NONE);

    for (i = 0; i < POINTS; i++)
	for (j = 0; j < POINTS; j++) {
	    cairo_set_source_surface (cr, surface,
				      2 * i + i * STEP, 2 * j + j * STEP);
	    cairo_pattern_set_filter (cairo_get_source (cr),
				      CAIRO_FILTER_NEAREST);
	    cairo_paint (cr);
	}

    return CAIRO_TEST_SUCCESS;
}

int
main (void)
{
    return cairo_test (&test);
}