72 lines
1.8 KiB
C++
72 lines
1.8 KiB
C++
// 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
|