cairo/test/font-variations.c

/*
 * Copyright © 2017 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: MAtthias Clasen <mclasen@redhat.com>
 */

#include "cairo-test.h"

#include <assert.h>

#if CAIRO_HAS_FC_FONT
#include <ft2build.h>
#include FT_FREETYPE_H
#include FT_MULTIPLE_MASTERS_H
#include <fontconfig/fontconfig.h>
#include "cairo-ft.h"
#endif

#define FloatToFixed(f) ((FT_Fixed)((f)*65536))

static cairo_test_status_t
test_variation (cairo_test_context_t *ctx,
                const char           *input,
                const char           *tag,
                int                   def,
                float                 expected_value)
{
    cairo_font_face_t *font_face;
    cairo_scaled_font_t *scaled_font;
    cairo_matrix_t matrix;
    cairo_font_options_t *options;
    cairo_status_t status;

    FT_Face ft_face;
    FT_MM_Var *ft_mm_var;
    FT_Error ret;
    FT_Fixed coords[20];
    unsigned int i;

#if CAIRO_HAS_FC_FONT
    FcPattern *pattern;

#ifndef FC_FONT_VARIATIONS
#define FC_FONT_VARIATIONS "fontvariations"
#endif

    /* we need a font that has variations */
    pattern = FcPatternBuild (NULL,
                              FC_FAMILY, FcTypeString, (FcChar8*)"Adobe Variable Font Prototype",
                              FC_FONT_VARIATIONS, FcTypeString, input,
                              NULL);
    font_face = cairo_ft_font_face_create_for_pattern (pattern);
    status = cairo_font_face_status (font_face);
    FcPatternDestroy (pattern);

    if (status != CAIRO_STATUS_SUCCESS) {
        cairo_test_log (ctx, "Failed to create font face");
        return CAIRO_TEST_FAILURE;
    }

    cairo_matrix_init_identity (&matrix);
    options = cairo_font_options_create ();
    if (cairo_font_options_status (options) != CAIRO_STATUS_SUCCESS) {
        cairo_test_log (ctx, "Failed to create font options");
        return CAIRO_TEST_FAILURE;
    }

    cairo_font_options_set_variations (options, "wdth=200,wght=300");
    if (cairo_font_options_status (options) != CAIRO_STATUS_SUCCESS) {
        cairo_test_log (ctx, "Failed to set variations");
        return CAIRO_TEST_FAILURE;
    }

    if (strcmp (cairo_font_options_get_variations (options), "wdth=200,wght=300") != 0) {
        cairo_test_log (ctx, "Failed to verify variations");
        return CAIRO_TEST_FAILURE;
    }

    scaled_font = cairo_scaled_font_create (font_face, &matrix, &matrix, options);
    status = cairo_scaled_font_status (scaled_font);

    if (status != CAIRO_STATUS_SUCCESS) {
        cairo_test_log (ctx, "Failed to create scaled font");
        return CAIRO_TEST_FAILURE;
    }

    ft_face = cairo_ft_scaled_font_lock_face (scaled_font);
    if (cairo_scaled_font_status (scaled_font) != CAIRO_STATUS_SUCCESS) {
        cairo_test_log (ctx, "Failed to get FT_Face");
        return CAIRO_TEST_FAILURE;
    }
    if (strcmp (ft_face->family_name, "Adobe Variable Font Prototype") != 0) {
        cairo_test_log (ctx, "This test requires the font \"Adobe Variable Font Prototype\" (https://github.com/adobe-fonts/adobe-variable-font-prototype/releases)");
        return CAIRO_TEST_FAILURE;
    }

    ret = FT_Get_MM_Var (ft_face, &ft_mm_var);
    if (ret != 0) {
        cairo_test_log (ctx, "Failed to get MM");
        return CAIRO_TEST_FAILURE;
    }

    ret = FT_Get_Var_Design_Coordinates (ft_face, 20, coords);
    if (ret != 0) {
        cairo_test_log (ctx, "Failed to get coords");
        return CAIRO_TEST_FAILURE;
    }

    for (i = 0; i < ft_mm_var->num_axis; i++) {
        FT_Var_Axis *axis = &ft_mm_var->axis[i];
        cairo_test_log (ctx, "axis %s, value %g\n", axis->name, coords[i] / 65536.);
    }
    for (i = 0; i < ft_mm_var->num_axis; i++) {
        FT_Var_Axis *axis = &ft_mm_var->axis[i];
        if (axis->tag == FT_MAKE_TAG(tag[0], tag[1], tag[2], tag[3])) {
            if (def) {
                if (coords[i] != axis->def) {
                    cairo_test_log (ctx, "Axis %s: not default value (%g != %g)",
                                    axis->name, coords[i] / 65536., axis->def / 65536.);
                    return CAIRO_TEST_FAILURE;
                }
            }
            else {
                if (coords[i] != FloatToFixed(expected_value)) {
                    cairo_test_log (ctx, "Axis %s: not expected value (%g != %g)",
                                    axis->name, coords[i] / 65536., expected_value);
                    return CAIRO_TEST_FAILURE;
                }
            }
        }
        else {
        }
    }

    cairo_ft_scaled_font_unlock_face (scaled_font);

    cairo_scaled_font_destroy (scaled_font);
    cairo_font_options_destroy (options);
    cairo_font_face_destroy (font_face);

    return CAIRO_TEST_SUCCESS;
#else
    return CAIRO_TEST_UNTESTED;
#endif
}

static cairo_test_status_t
preamble (cairo_test_context_t *ctx)
{
    cairo_test_status_t status = CAIRO_TEST_SUCCESS;
    struct { const char *input;
             const char *tag;
             int expected_default;
             float expected_value;
    } tests[] = {
      { "wdth=200,wght=300", "wght", 0, 200.0 }, // valid
      { "wdth=200.5,wght=300", "wght", 0, 200.5 }, // valid, using decimal dot
      { "wdth 200 , wght=300", "wght", 0, 200.0 }, // valid, without =
      { "wdth = 200", "wght", 0, 200.0 }, // valid, whitespace and =
      { "CNTR=20", "wght", 1, 0.0 }, // valid, not setting wght
      { "weight=100", "wght", 1, 0.0 }, // not a valid tag
      { NULL, 0 }
    };
    int i;

    for (i = 0; tests[i].input; i++) {
       status = test_variation (ctx,
                                tests[i].input,
                                tests[i].tag,
                                tests[i].expected_default,
                                tests[i].expected_value);
       if (status != CAIRO_TEST_SUCCESS)
           return status;
    }

    return CAIRO_TEST_SUCCESS;
}

CAIRO_TEST (font_variations,
	    "Test font variations",
	    "fonts", /* keywords */
	    NULL, /* requirements */
	    9, 11,
	    preamble, NULL)