1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
|
// Scintilla source code edit control
/** @file Partitioning.h
** Data structure used to partition an interval. Used for holding line start/end positions.
**/
// Copyright 1998-2007 by Neil Hodgson <neilh@scintilla.org>
// The License.txt file describes the conditions under which this software may be distributed.
#ifndef PARTITIONING_H
#define PARTITIONING_H
/// A split vector of integers with a method for adding a value to all elements
/// in a range.
/// Used by the Partitioning class.
class SplitVectorWithRangeAdd : public SplitVector<int> {
public:
SplitVectorWithRangeAdd(int growSize_) {
SetGrowSize(growSize_);
ReAllocate(growSize_);
}
~SplitVectorWithRangeAdd() {
}
void RangeAddDelta(int start, int end, int delta) {
// end is 1 past end, so end-start is number of elements to change
int i = 0;
int rangeLength = end - start;
int range1Length = rangeLength;
int part1Left = part1Length - start;
if (range1Length > part1Left)
range1Length = part1Left;
while (i < range1Length) {
body[start++] += delta;
i++;
}
start += gapLength;
while (i < rangeLength) {
body[start++] += delta;
i++;
}
}
};
/// Divide an interval into multiple partitions.
/// Useful for breaking a document down into sections such as lines.
class Partitioning {
private:
// To avoid calculating all the partition positions whenever any text is inserted
// there may be a step somewhere in the list.
int stepPartition;
int stepLength;
SplitVectorWithRangeAdd *body;
// Move step forward
void ApplyStep(int partitionUpTo) {
if (stepLength != 0) {
body->RangeAddDelta(stepPartition+1, partitionUpTo + 1, stepLength);
}
stepPartition = partitionUpTo;
if (stepPartition >= body->Length()-1) {
stepPartition = body->Length()-1;
stepLength = 0;
}
}
// Move step backward
void BackStep(int partitionDownTo) {
if (stepLength != 0) {
body->RangeAddDelta(partitionDownTo+1, stepPartition+1, -stepLength);
}
stepPartition = partitionDownTo;
}
void Allocate(int growSize) {
body = new SplitVectorWithRangeAdd(growSize);
stepPartition = 0;
stepLength = 0;
body->Insert(0, 0); // This value stays 0 for ever
body->Insert(1, 0); // This is the end of the first partition and will be the start of the second
}
public:
Partitioning(int growSize) {
Allocate(growSize);
}
~Partitioning() {
delete body;
body = 0;
}
int Partitions() const {
return body->Length()-1;
}
void InsertPartition(int partition, int pos) {
if (stepPartition < partition) {
ApplyStep(partition);
}
body->Insert(partition, pos);
stepPartition++;
}
void SetPartitionStartPosition(int partition, int pos) {
ApplyStep(partition+1);
if ((partition < 0) || (partition > body->Length())) {
return;
}
body->SetValueAt(partition, pos);
}
void InsertText(int partitionInsert, int delta) {
// Point all the partitions after the insertion point further along in the buffer
if (stepLength != 0) {
if (partitionInsert >= stepPartition) {
// Fill in up to the new insertion point
ApplyStep(partitionInsert);
stepLength += delta;
} else if (partitionInsert >= (stepPartition - body->Length() / 10)) {
// Close to step but before so move step back
BackStep(partitionInsert);
stepLength += delta;
} else {
ApplyStep(body->Length()-1);
stepPartition = partitionInsert;
stepLength = delta;
}
} else {
stepPartition = partitionInsert;
stepLength = delta;
}
}
void RemovePartition(int partition) {
if (partition > stepPartition) {
ApplyStep(partition);
stepPartition--;
} else {
stepPartition--;
}
body->Delete(partition);
}
int PositionFromPartition(int partition) const {
PLATFORM_ASSERT(partition >= 0);
PLATFORM_ASSERT(partition < body->Length());
if ((partition < 0) || (partition >= body->Length())) {
return 0;
}
int pos = body->ValueAt(partition);
if (partition > stepPartition)
pos += stepLength;
return pos;
}
int PartitionFromPosition(int pos) const {
if (body->Length() <= 1)
return 0;
if (pos >= (PositionFromPartition(body->Length()-1)))
return body->Length() - 1 - 1;
int lower = 0;
int upper = body->Length()-1;
do {
int middle = (upper + lower + 1) / 2; // Round high
int posMiddle = body->ValueAt(middle);
if (middle > stepPartition)
posMiddle += stepLength;
if (pos < posMiddle) {
upper = middle - 1;
} else {
lower = middle;
}
} while (lower < upper);
return lower;
}
void DeleteAll() {
int growSize = body->GetGrowSize();
delete body;
Allocate(growSize);
}
};
#endif
|