1 /*
2  * Copyright 2011 Google Inc. All Rights Reserved.
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "sfntly/table/core/horizontal_metrics_table.h"
18 #include "sfntly/port/exception_type.h"
19 
20 namespace sfntly {
21 /******************************************************************************
22  * HorizontalMetricsTable class
23  ******************************************************************************/
~HorizontalMetricsTable()24 HorizontalMetricsTable::~HorizontalMetricsTable() {}
25 
NumberOfHMetrics()26 int32_t HorizontalMetricsTable::NumberOfHMetrics() {
27   return num_hmetrics_;
28 }
29 
NumberOfLSBs()30 int32_t HorizontalMetricsTable::NumberOfLSBs() {
31   return num_glyphs_ - num_hmetrics_;
32 }
33 
HMetricAdvanceWidth(int32_t entry)34 int32_t HorizontalMetricsTable::HMetricAdvanceWidth(int32_t entry) {
35   if (entry > num_hmetrics_) {
36 #if !defined (SFNTLY_NO_EXCEPTION)
37     throw IndexOutOfBoundException();
38 #endif
39     return 0;
40   }
41   int32_t offset = Offset::kHMetricsStart + (entry * Offset::kHMetricsSize) +
42                    Offset::kHMetricsAdvanceWidth;
43   return data_->ReadUShort(offset);
44 }
45 
HMetricLSB(int32_t entry)46 int32_t HorizontalMetricsTable::HMetricLSB(int32_t entry) {
47   if (entry > num_hmetrics_) {
48 #if !defined (SFNTLY_NO_EXCEPTION)
49     throw IndexOutOfBoundException();
50 #endif
51     return 0;
52   }
53   int32_t offset = Offset::kHMetricsStart + (entry * Offset::kHMetricsSize) +
54                    Offset::kHMetricsLeftSideBearing;
55   return data_->ReadShort(offset);
56 }
57 
LsbTableEntry(int32_t entry)58 int32_t HorizontalMetricsTable::LsbTableEntry(int32_t entry) {
59   if (entry > num_hmetrics_) {
60 #if !defined (SFNTLY_NO_EXCEPTION)
61     throw IndexOutOfBoundException();
62 #endif
63     return 0;
64   }
65   int32_t offset = Offset::kHMetricsStart + (entry * Offset::kHMetricsSize) +
66                    Offset::kLeftSideBearingSize;
67   return data_->ReadShort(offset);
68 }
69 
AdvanceWidth(int32_t glyph_id)70 int32_t HorizontalMetricsTable::AdvanceWidth(int32_t glyph_id) {
71   if (glyph_id < num_hmetrics_) {
72     return HMetricAdvanceWidth(glyph_id);
73   }
74   return HMetricAdvanceWidth(glyph_id - num_hmetrics_);
75 }
76 
LeftSideBearing(int32_t glyph_id)77 int32_t HorizontalMetricsTable::LeftSideBearing(int32_t glyph_id) {
78   if (glyph_id < num_hmetrics_) {
79     return HMetricLSB(glyph_id);
80   }
81   return LsbTableEntry(glyph_id - num_hmetrics_);
82 }
83 
HorizontalMetricsTable(Header * header,ReadableFontData * data,int32_t num_hmetrics,int32_t num_glyphs)84 HorizontalMetricsTable::HorizontalMetricsTable(Header* header,
85                                                ReadableFontData* data,
86                                                int32_t num_hmetrics,
87                                                int32_t num_glyphs)
88     : Table(header, data),
89       num_hmetrics_(num_hmetrics),
90       num_glyphs_(num_glyphs) {
91 }
92 
93 /******************************************************************************
94  * HorizontalMetricsTable::Builder class
95  ******************************************************************************/
Builder(Header * header,WritableFontData * data)96 HorizontalMetricsTable::Builder::Builder(Header* header, WritableFontData* data)
97     : TableBasedTableBuilder(header, data), num_hmetrics_(-1), num_glyphs_(-1) {
98 }
99 
Builder(Header * header,ReadableFontData * data)100 HorizontalMetricsTable::Builder::Builder(Header* header, ReadableFontData* data)
101     : TableBasedTableBuilder(header, data), num_hmetrics_(-1), num_glyphs_(-1) {
102 }
103 
~Builder()104 HorizontalMetricsTable::Builder::~Builder() {}
105 
106 CALLER_ATTACH FontDataTable*
SubBuildTable(ReadableFontData * data)107     HorizontalMetricsTable::Builder::SubBuildTable(ReadableFontData* data) {
108   FontDataTablePtr table =
109       new HorizontalMetricsTable(header(), data, num_hmetrics_, num_glyphs_);
110   return table.Detach();
111 }
112 
113 CALLER_ATTACH HorizontalMetricsTable::Builder*
CreateBuilder(Header * header,WritableFontData * data)114     HorizontalMetricsTable::Builder::CreateBuilder(Header* header,
115                                                    WritableFontData* data) {
116   Ptr<HorizontalMetricsTable::Builder> builder;
117   builder = new HorizontalMetricsTable::Builder(header, data);
118   return builder.Detach();
119 }
120 
SetNumberOfHMetrics(int32_t num_hmetrics)121 void HorizontalMetricsTable::Builder::SetNumberOfHMetrics(
122     int32_t num_hmetrics) {
123   assert(num_hmetrics >= 0);
124   num_hmetrics_ = num_hmetrics;
125   HorizontalMetricsTable* table =
126       down_cast<HorizontalMetricsTable*>(this->GetTable());
127   table->num_hmetrics_ = num_hmetrics;
128 }
129 
SetNumGlyphs(int32_t num_glyphs)130 void HorizontalMetricsTable::Builder::SetNumGlyphs(int32_t num_glyphs) {
131   assert(num_glyphs >= 0);
132   num_glyphs_ = num_glyphs;
133   HorizontalMetricsTable* table =
134       down_cast<HorizontalMetricsTable*>(this->GetTable());
135   table->num_glyphs_ = num_glyphs;
136 }
137 
138 }  // namespace sfntly
139