harfbuzz/src/hb-ot-color.cc

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/*
* Copyright © 2016 Google, Inc.
* Copyright © 2018 Ebrahim Byagowi
*
* 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): Sascha Brawer, Behdad Esfahbod
*/
#include "hb.hh"
#ifndef HB_NO_COLOR
#include "hb-ot.h"
#include "hb-ot-color-cbdt-table.hh"
#include "hb-ot-color-colr-table.hh"
#include "hb-ot-color-cpal-table.hh"
#include "hb-ot-color-sbix-table.hh"
#include "hb-ot-color-svg-table.hh"
/**
* SECTION:hb-ot-color
* @title: hb-ot-color
* @short_description: OpenType Color Fonts
* @include: hb-ot.h
*
* Functions for fetching color-font information from OpenType font faces.
*
* HarfBuzz supports `COLR`/`CPAL`, `sbix`, `CBDT`, and `SVG` color fonts.
**/
/*
* CPAL
*/
/**
* hb_ot_color_has_palettes:
* @face: #hb_face_t to work upon
*
* Tests whether a face includes a `CPAL` color-palette table.
*
* Return value: `true` if data found, `false` otherwise
*
* Since: 2.1.0
*/
hb_bool_t
hb_ot_color_has_palettes (hb_face_t *face)
{
return face->table.CPAL->has_data ();
}
/**
* hb_ot_color_palette_get_count:
* @face: #hb_face_t to work upon
*
* Fetches the number of color palettes in a face.
*
* Return value: the number of palettes found
*
* Since: 2.1.0
*/
unsigned int
hb_ot_color_palette_get_count (hb_face_t *face)
{
return face->table.CPAL->get_palette_count ();
}
/**
* hb_ot_color_palette_get_name_id:
* @face: #hb_face_t to work upon
* @palette_index: The index of the color palette
*
* Fetches the `name` table Name ID that provides display names for
* a `CPAL` color palette.
*
* Palette display names can be generic (e.g., "Default") or provide
* specific, themed names (e.g., "Spring", "Summer", "Fall", and "Winter").
*
* Return value: the Named ID found for the palette.
* If the requested palette has no name the result is #HB_OT_NAME_ID_INVALID.
*
* Since: 2.1.0
*/
hb_ot_name_id_t
hb_ot_color_palette_get_name_id (hb_face_t *face,
unsigned int palette_index)
{
return face->table.CPAL->get_palette_name_id (palette_index);
}
/**
* hb_ot_color_palette_color_get_name_id:
* @face: #hb_face_t to work upon
* @color_index: The index of the color
*
* Fetches the `name` table Name ID that provides display names for
* the specified color in a face's `CPAL` color palette.
*
* Display names can be generic (e.g., "Background") or specific
* (e.g., "Eye color").
*
* Return value: the Name ID found for the color.
*
* Since: 2.1.0
*/
hb_ot_name_id_t
hb_ot_color_palette_color_get_name_id (hb_face_t *face,
unsigned int color_index)
{
return face->table.CPAL->get_color_name_id (color_index);
}
/**
* hb_ot_color_palette_get_flags:
* @face: #hb_face_t to work upon
* @palette_index: The index of the color palette
*
* Fetches the flags defined for a color palette.
*
* Return value: the #hb_ot_color_palette_flags_t of the requested color palette
*
* Since: 2.1.0
*/
hb_ot_color_palette_flags_t
hb_ot_color_palette_get_flags (hb_face_t *face,
unsigned int palette_index)
{
return face->table.CPAL->get_palette_flags (palette_index);
}
/**
* hb_ot_color_palette_get_colors:
* @face: #hb_face_t to work upon
* @palette_index: the index of the color palette to query
* @start_offset: offset of the first color to retrieve
* @color_count: (inout) (optional): Input = the maximum number of colors to return;
* Output = the actual number of colors returned (may be zero)
* @colors: (out) (array length=color_count) (nullable): The array of #hb_color_t records found
*
* Fetches a list of the colors in a color palette.
*
* After calling this function, @colors will be filled with the palette
* colors. If @colors is NULL, the function will just return the number
* of total colors without storing any actual colors; this can be used
* for allocating a buffer of suitable size before calling
* hb_ot_color_palette_get_colors() a second time.
*
* Return value: the total number of colors in the palette
*
* Since: 2.1.0
*/
unsigned int
hb_ot_color_palette_get_colors (hb_face_t *face,
unsigned int palette_index,
unsigned int start_offset,
unsigned int *colors_count /* IN/OUT. May be NULL. */,
hb_color_t *colors /* OUT. May be NULL. */)
{
return face->table.CPAL->get_palette_colors (palette_index, start_offset, colors_count, colors);
}
/*
* COLR
*/
/**
* hb_ot_color_has_layers:
* @face: #hb_face_t to work upon
*
* Tests whether a face includes any `COLR` color layers.
*
* Return value: `true` if data found, `false` otherwise
*
* Since: 2.1.0
*/
hb_bool_t
hb_ot_color_has_layers (hb_face_t *face)
{
return face->table.COLR->has_data ();
}
/**
* hb_ot_color_glyph_get_layers:
* @face: #hb_face_t to work upon
* @glyph: The glyph index to query
* @start_offset: offset of the first layer to retrieve
* @layer_count: (inout) (optional): Input = the maximum number of layers to return;
* Output = the actual number of layers returned (may be zero)
* @layers: (out) (array length=layer_count) (nullable): The array of layers found
*
* Fetches a list of all color layers for the specified glyph index in the specified
* face. The list returned will begin at the offset provided.
*
* Return value: Total number of layers available for the glyph index queried
*
* Since: 2.1.0
*/
unsigned int
hb_ot_color_glyph_get_layers (hb_face_t *face,
hb_codepoint_t glyph,
unsigned int start_offset,
unsigned int *layer_count, /* IN/OUT. May be NULL. */
hb_ot_color_layer_t *layers /* OUT. May be NULL. */)
{
return face->table.COLR->get_glyph_layers (glyph, start_offset, layer_count, layers);
}
/*
* SVG
*/
/**
* hb_ot_color_has_svg:
* @face: #hb_face_t to work upon.
*
* Tests whether a face includes any `SVG` glyph images.
*
* Return value: `true` if data found, `false` otherwise.
*
* Since: 2.1.0
*/
hb_bool_t
hb_ot_color_has_svg (hb_face_t *face)
{
return face->table.SVG->has_data ();
}
/**
* hb_ot_color_glyph_reference_svg:
* @face: #hb_face_t to work upon
* @glyph: a svg glyph index
*
* Fetches the SVG document for a glyph. The blob may be either plain text or gzip-encoded.
*
* If the glyph has no SVG document, the singleton empty blob is returned.
*
* Return value: (transfer full): An #hb_blob_t containing the SVG document of the glyph, if available
*
* Since: 2.1.0
*/
hb_blob_t *
hb_ot_color_glyph_reference_svg (hb_face_t *face, hb_codepoint_t glyph)
{
return face->table.SVG->reference_blob_for_glyph (glyph);
}
/*
* PNG: CBDT or sbix
*/
/**
* hb_ot_color_has_png:
* @face: #hb_face_t to work upon
*
* Tests whether a face has PNG glyph images (either in `CBDT` or `sbix` tables).
*
* Return value: `true` if data found, `false` otherwise
*
* Since: 2.1.0
*/
hb_bool_t
hb_ot_color_has_png (hb_face_t *face)
{
return face->table.CBDT->has_data () || face->table.sbix->has_data ();
}
/**
* hb_ot_color_glyph_reference_png:
* @font: #hb_font_t to work upon
* @glyph: a glyph index
*
* Fetches the PNG image for a glyph. This function takes a font object, not a face object,
* as input. To get an optimally sized PNG blob, the UPEM value must be set on the @font
* object. If UPEM is unset, the blob returned will be the largest PNG available.
*
* If the glyph has no PNG image, the singleton empty blob is returned.
*
* Return value: (transfer full): An #hb_blob_t containing the PNG image for the glyph, if available
*
* Since: 2.1.0
*/
hb_blob_t *
hb_ot_color_glyph_reference_png (hb_font_t *font, hb_codepoint_t glyph)
{
hb_blob_t *blob = hb_blob_get_empty ();
if (font->face->table.sbix->has_data ())
blob = font->face->table.sbix->reference_png (font, glyph, nullptr, nullptr, nullptr);
if (!blob->length && font->face->table.CBDT->has_data ())
blob = font->face->table.CBDT->reference_png (font, glyph);
return blob;
}
#endif