/* * Copyright © 2011 Google, Inc. * * This is part of HarfBuzz, a text shaping library. * * Permission is hereby granted, without written agreement and without * license or royalty fees, to use, copy, modify, and distribute this * software and its documentation for any purpose, provided that the * above copyright notice and the following two paragraphs appear in * all copies of this software. * * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH * DAMAGE. * * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. * * Google Author(s): Behdad Esfahbod */ #ifndef VIEW_CAIRO_HH #define VIEW_CAIRO_HH #include "view-options.hh" #include "output-options.hh" #include "helper-cairo.hh" struct view_cairo_t : view_options_t, output_options_t<> { ~view_cairo_t () { cairo_debug_reset_static_data (); } void add_options (option_parser_t *parser) { parser->set_summary ("View text with given font."); view_options_t::add_options (parser); output_options_t::add_options (parser, helper_cairo_supported_formats); } void init (hb_buffer_t *buffer, const font_options_t *font_opts) { lines = g_array_new (false, false, sizeof (helper_cairo_line_t)); subpixel_bits = font_opts->subpixel_bits; } void new_line () {} void consume_text (hb_buffer_t *buffer, const char *text, unsigned int text_len, hb_bool_t utf8_clusters) {} void error (const char *message) { g_printerr ("%s: %s\n", g_get_prgname (), message); } void consume_glyphs (hb_buffer_t *buffer, const char *text, unsigned int text_len, hb_bool_t utf8_clusters) { direction = hb_buffer_get_direction (buffer); helper_cairo_line_t l (text, text_len, buffer, utf8_clusters, subpixel_bits); g_array_append_val (lines, l); } void finish (hb_buffer_t *buffer, const font_options_t *font_opts) { render (font_opts); for (unsigned int i = 0; i < lines->len; i++) { helper_cairo_line_t &line = g_array_index (lines, helper_cairo_line_t, i); line.finish (); } #if GLIB_CHECK_VERSION (2, 22, 0) g_array_unref (lines); #else g_array_free (lines, TRUE); #endif } protected: void render (const font_options_t *font_opts); hb_direction_t direction = HB_DIRECTION_INVALID; // Remove this, make segment_properties accessible GArray *lines = nullptr; unsigned subpixel_bits = 0; }; inline void view_cairo_t::render (const font_options_t *font_opts) { bool vertical = HB_DIRECTION_IS_VERTICAL (direction); int vert = vertical ? 1 : 0; int horiz = vertical ? 0 : 1; int x_sign = font_opts->font_size_x < 0 ? -1 : +1; int y_sign = font_opts->font_size_y < 0 ? -1 : +1; hb_font_t *font = font_opts->font; if (!have_font_extents) { hb_font_extents_t hb_extents; hb_font_get_extents_for_direction (font, direction, &hb_extents); font_extents.ascent = scalbn ((double) hb_extents.ascender, - (int) subpixel_bits); font_extents.descent = -scalbn ((double) hb_extents.descender, - (int) subpixel_bits); font_extents.line_gap = scalbn ((double) hb_extents.line_gap, - (int) subpixel_bits); have_font_extents = true; } double ascent = y_sign * font_extents.ascent; double descent = y_sign * font_extents.descent; double line_gap = y_sign * font_extents.line_gap + line_space; double leading = ascent + descent + line_gap; /* Calculate surface size. */ double w = 0, h = 0; (vertical ? w : h) = (int) lines->len * leading - (font_extents.line_gap + line_space); (vertical ? h : w) = 0; for (unsigned int i = 0; i < lines->len; i++) { helper_cairo_line_t &line = g_array_index (lines, helper_cairo_line_t, i); double x_advance, y_advance; line.get_advance (&x_advance, &y_advance); if (vertical) h = MAX (h, y_sign * y_advance); else w = MAX (w, x_sign * x_advance); } cairo_scaled_font_t *scaled_font = helper_cairo_create_scaled_font (font_opts, this); /* See if font needs color. */ cairo_content_t content = CAIRO_CONTENT_ALPHA; if (helper_cairo_scaled_font_has_color (scaled_font)) content = CAIRO_CONTENT_COLOR; /* Create surface. */ cairo_t *cr = helper_cairo_create_context (w + margin.l + margin.r, h + margin.t + margin.b, this, this, content); cairo_set_scaled_font (cr, scaled_font); /* Setup coordinate system. */ cairo_translate (cr, margin.l, margin.t); if (vertical) cairo_translate (cr, w - ascent, /* We currently always stack lines right to left */ y_sign < 0 ? h : 0); else { cairo_translate (cr, x_sign < 0 ? w : 0, y_sign < 0 ? descent : ascent); } /* Draw. */ cairo_translate (cr, +vert * leading, -horiz * leading); for (unsigned int i = 0; i < lines->len; i++) { helper_cairo_line_t &l = g_array_index (lines, helper_cairo_line_t, i); cairo_translate (cr, -vert * leading, +horiz * leading); if (show_extents) { cairo_save (cr); cairo_set_source_rgba (cr, 1., 0., 0., .5); cairo_set_line_width (cr, 10); cairo_set_line_cap (cr, CAIRO_LINE_CAP_ROUND); for (unsigned i = 0; i < l.num_glyphs; i++) { cairo_move_to (cr, l.glyphs[i].x, l.glyphs[i].y); cairo_rel_line_to (cr, 0, 0); } cairo_stroke (cr); cairo_restore (cr); cairo_save (cr); cairo_set_source_rgba (cr, 1., 0., 1., .5); cairo_set_line_width (cr, 3); for (unsigned i = 0; i < l.num_glyphs; i++) { hb_glyph_extents_t hb_extents; hb_font_get_glyph_extents (font, l.glyphs[i].index, &hb_extents); double x1 = scalbn ((double) hb_extents.x_bearing, - (int) subpixel_bits); double y1 = -scalbn ((double) hb_extents.y_bearing, - (int) subpixel_bits); double width = scalbn ((double) hb_extents.width, - (int) subpixel_bits); double height = -scalbn ((double) hb_extents.height, - (int) subpixel_bits); cairo_rectangle (cr, l.glyphs[i].x + x1, l.glyphs[i].y + y1, width, height); } cairo_stroke (cr); cairo_restore (cr); } if (l.num_clusters) cairo_show_text_glyphs (cr, l.utf8, l.utf8_len, l.glyphs, l.num_glyphs, l.clusters, l.num_clusters, l.cluster_flags); else cairo_show_glyphs (cr, l.glyphs, l.num_glyphs); } /* Clean up. */ helper_cairo_destroy_context (cr); cairo_scaled_font_destroy (scaled_font); } #endif