blob: 4c40c5eb77e100c4f1b33b5432063cbc021fa7dc [file] [log] [blame]
// Copyright (c) 2009-2017 The OTS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "ltsh.h"
#include "maxp.h"
// LTSH - Linear Threshold
// http://www.microsoft.com/typography/otspec/ltsh.htm
namespace ots {
bool OpenTypeLTSH::Parse(const uint8_t *data, size_t length) {
Buffer table(data, length);
OpenTypeMAXP *maxp = static_cast<OpenTypeMAXP*>(
GetFont()->GetTypedTable(OTS_TAG_MAXP));
if (!maxp) {
return Error("Required maxp table is missing");
}
uint16_t num_glyphs = 0;
if (!table.ReadU16(&this->version) ||
!table.ReadU16(&num_glyphs)) {
return Error("Failed to read table header");
}
if (this->version != 0) {
return Drop("Unsupported version: %u", this->version);
}
if (num_glyphs != maxp->num_glyphs) {
return Drop("Bad numGlyphs: %u", num_glyphs);
}
this->ypels.reserve(num_glyphs);
for (unsigned i = 0; i < num_glyphs; ++i) {
uint8_t pel = 0;
if (!table.ReadU8(&pel)) {
return Error("Failed to read pixels for glyph %d", i);
}
this->ypels.push_back(pel);
}
return true;
}
bool OpenTypeLTSH::Serialize(OTSStream *out) {
const uint16_t num_ypels = static_cast<uint16_t>(this->ypels.size());
if (num_ypels != this->ypels.size() ||
!out->WriteU16(this->version) ||
!out->WriteU16(num_ypels)) {
return Error("Failed to write table header");
}
for (uint16_t i = 0; i < num_ypels; ++i) {
if (!out->Write(&(this->ypels[i]), 1)) {
return Error("Failed to write pixel size for glyph %d", i);
}
}
return true;
}
bool OpenTypeLTSH::ShouldSerialize() {
return Table::ShouldSerialize() &&
// this table is not for CFF fonts.
GetFont()->GetTable(OTS_TAG_GLYF) != NULL;
}
} // namespace ots