/*

 * Copyright © 2006 Red Hat, Inc.

 *

 * 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

 * Red Hat, Inc. not be used in advertising or publicity pertaining to

 * distribution of the software without specific, written prior

 * permission. Red Hat, Inc. makes no representations about the

 * suitability of this software for any purpose.  It is provided "as

 * is" without express or implied warranty.

 *

 * RED HAT, INC. DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS

 * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND

 * FITNESS, IN NO EVENT SHALL RED HAT, INC. 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: Carl D. Worth <cworth@cworth.org>

 */

#include "cairo-test.h"

/* This test exercises the various interactions between

 * cairo_set_line_width and cairo_scale. Specifically it shows how

 * separate transformations can affect the pen for stroking compared

 * to the path itself.

 *

 * This was inspired by an image by Maxim Shemanarev demonstrating the

 * flexible-pipeline nature of his Antigrain Geometry project:

 *

 *	http://antigrain.com/tips/line_alignment/conv_order.gif

 *

 * It also uncovered some behavior in cairo that I found surprising.

 * Namely, cairo_set_line_width was not transforming the width

 * according the the current CTM, but instead delaying that

 * transformation until the time of cairo_stroke.

 *

 * This delayed behavior was released in cairo 1.0 so we're going to

 * document this as the way cairo_set_line_width works rather than

 * considering this a bug.

 */

#define LINE_WIDTH 13

#define SPLINE 50.0

#define XSCALE  0.5

#define YSCALE  2.0

#define WIDTH (XSCALE * SPLINE * 6.0)

#define HEIGHT (YSCALE * SPLINE * 2.0)

static void

{

    {

		       - SPLINE, 0);

			- SPLINE / 4, - SPLINE,

			  SPLINE / 4,   SPLINE,

			  SPLINE, 0);

    }

/* If we scale before setting the line width or creating the path,

 * then obviously both will be scaled. */

static void

{

/* This is used to verify the results of

 * scale_then_set_line_width_and_stroke.

 *

 * It uses save/restore pairs to isolate the scaling of the path and

 * line_width and ensures that both are scaled.

 */

static void

{

    {

    }

    {

    }

/* This is the case that was surprising.

 *

 * Setting the line width before scaling doesn't change anything. The

 * line width will be interpreted under the CTM in effect at the time

 * of cairo_stroke, so the line width will be scaled as well as the

 * path here.

 */

static void

{

/* Here then is the way to achieve the alternate result.

 *

 * This uses save/restore pairs to isolate the scaling of the path and

 * line_width and ensures that the path is scaled while the line width

 * is not.

 */

static void

{

    {

    }

    {

    }

static cairo_test_status_t

{

    int i;

	scale_then_set_line_width_and_stroke,

	scale_path_and_line_width,

	set_line_width_then_scale_and_stroke,

	scale_path_not_line_width

    };

    }

}

	    "Tests interaction of cairo_set_line_width with cairo_scale",

	    "stroke", /* keywords */

	    NULL, /* requirements */

	    WIDTH, HEIGHT,

	    NULL, draw)