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9cc9bbe146
This is the initial draft of Minikin, a library intended to perform text layout functions. This version does basic weight selection and font runs for scripts, and also has a simple renderer for drawing into bitmaps, but is lacking measurement, line breaking, and a number of other important features. It also lacks caching and other performance refinements. Change-Id: I789a2e47d11d71202dc84b4751b51a5e2cd9c451
44 lines
1.4 KiB
C++
44 lines
1.4 KiB
C++
/*
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* Copyright (C) 2013 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#include <stdlib.h>
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#include <stdint.h>
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#include <minikin/AnalyzeStyle.h>
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namespace android {
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// should we have a single FontAnalyzer class this stuff lives in, to avoid dup?
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static int32_t readU16(const uint8_t* data, size_t offset) {
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return data[offset] << 8 | data[offset + 1];
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}
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bool analyzeStyle(const uint8_t* os2_data, size_t os2_size, int* weight, bool* italic) {
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const size_t kUsWeightClassOffset = 4;
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const size_t kFsSelectionOffset = 62;
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const uint16_t kItalicFlag = (1 << 0);
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if (os2_size < kFsSelectionOffset + 2) {
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return false;
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}
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uint16_t weightClass = readU16(os2_data, kUsWeightClassOffset);
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*weight = weightClass / 100;
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uint16_t fsSelection = readU16(os2_data, kFsSelectionOffset);
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*italic = (fsSelection & kItalicFlag) != 0;
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return true;
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}
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} // namespace android
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