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
|
// Copyright 2010 The draw2d Authors. All rights reserved.
// created: 06/12/2010 by Laurent Le Goff
package draw2d
import (
"math"
)
type PathConverter struct {
converter VertexConverter
ApproximationScale, AngleTolerance, CuspLimit float64
startX, startY, x, y float64
}
func NewPathConverter(converter VertexConverter) *PathConverter {
return &PathConverter{converter, 1, 0, 0, 0, 0, 0, 0}
}
func (c *PathConverter) Convert(paths ...*PathStorage) {
for _, path := range paths {
j := 0
for _, cmd := range path.commands {
j = j + c.ConvertCommand(cmd, path.vertices[j:]...)
}
c.converter.NextCommand(VertexStopCommand)
}
}
func (c *PathConverter) ConvertCommand(cmd PathCmd, vertices ...float64) int {
switch cmd {
case MoveTo:
c.x, c.y = vertices[0], vertices[1]
c.startX, c.startY = c.x, c.y
c.converter.NextCommand(VertexStopCommand)
c.converter.NextCommand(VertexStartCommand)
c.converter.Vertex(c.x, c.y)
return 2
case LineTo:
c.x, c.y = vertices[0], vertices[1]
if c.startX == c.x && c.startY == c.y {
c.converter.NextCommand(VertexCloseCommand)
}
c.converter.Vertex(c.x, c.y)
c.converter.NextCommand(VertexJoinCommand)
return 2
case QuadCurveTo:
quadraticBezier(c.converter, c.x, c.y, vertices[0], vertices[1], vertices[2], vertices[3], c.ApproximationScale, c.AngleTolerance)
c.x, c.y = vertices[2], vertices[3]
if c.startX == c.x && c.startY == c.y {
c.converter.NextCommand(VertexCloseCommand)
}
c.converter.Vertex(c.x, c.y)
return 4
case CubicCurveTo:
cubicBezier(c.converter, c.x, c.y, vertices[0], vertices[1], vertices[2], vertices[3], vertices[4], vertices[5], c.ApproximationScale, c.AngleTolerance, c.CuspLimit)
c.x, c.y = vertices[4], vertices[5]
if c.startX == c.x && c.startY == c.y {
c.converter.NextCommand(VertexCloseCommand)
}
c.converter.Vertex(c.x, c.y)
return 6
case ArcTo:
c.x, c.y = arc(c.converter, vertices[0], vertices[1], vertices[2], vertices[3], vertices[4], vertices[5], c.ApproximationScale)
if c.startX == c.x && c.startY == c.y {
c.converter.NextCommand(VertexCloseCommand)
}
c.converter.Vertex(c.x, c.y)
return 6
case Close:
c.converter.NextCommand(VertexCloseCommand)
c.converter.Vertex(c.startX, c.startY)
return 0
}
return 0
}
func (c *PathConverter) MoveTo(x, y float64) *PathConverter {
c.x, c.y = x, y
c.startX, c.startY = c.x, c.y
c.converter.NextCommand(VertexStopCommand)
c.converter.NextCommand(VertexStartCommand)
c.converter.Vertex(c.x, c.y)
return c
}
func (c *PathConverter) RMoveTo(dx, dy float64) *PathConverter {
c.MoveTo(c.x+dx, c.y+dy)
return c
}
func (c *PathConverter) LineTo(x, y float64) *PathConverter {
c.x, c.y = x, y
if c.startX == c.x && c.startY == c.y {
c.converter.NextCommand(VertexCloseCommand)
}
c.converter.Vertex(c.x, c.y)
c.converter.NextCommand(VertexJoinCommand)
return c
}
func (c *PathConverter) RLineTo(dx, dy float64) *PathConverter {
c.LineTo(c.x+dx, c.y+dy)
return c
}
func (c *PathConverter) QuadCurveTo(cx, cy, x, y float64) *PathConverter {
quadraticBezier(c.converter, c.x, c.y, cx, cy, x, y, c.ApproximationScale, c.AngleTolerance)
c.x, c.y = x, y
if c.startX == c.x && c.startY == c.y {
c.converter.NextCommand(VertexCloseCommand)
}
c.converter.Vertex(c.x, c.y)
return c
}
func (c *PathConverter) RQuadCurveTo(dcx, dcy, dx, dy float64) *PathConverter {
c.QuadCurveTo(c.x+dcx, c.y+dcy, c.x+dx, c.y+dy)
return c
}
func (c *PathConverter) CubicCurveTo(cx1, cy1, cx2, cy2, x, y float64) *PathConverter {
cubicBezier(c.converter, c.x, c.y, cx1, cy1, cx2, cy2, x, y, c.ApproximationScale, c.AngleTolerance, c.CuspLimit)
c.x, c.y = x, y
if c.startX == c.x && c.startY == c.y {
c.converter.NextCommand(VertexCloseCommand)
}
c.converter.Vertex(c.x, c.y)
return c
}
func (c *PathConverter) RCubicCurveTo(dcx1, dcy1, dcx2, dcy2, dx, dy float64) *PathConverter {
c.CubicCurveTo(c.x+dcx1, c.y+dcy1, c.x+dcx2, c.y+dcy2, c.x+dx, c.y+dy)
return c
}
func (c *PathConverter) ArcTo(cx, cy, rx, ry, startAngle, angle float64) *PathConverter {
endAngle := startAngle + angle
clockWise := true
if angle < 0 {
clockWise = false
}
// normalize
if clockWise {
for endAngle < startAngle {
endAngle += math.Pi * 2.0
}
} else {
for startAngle < endAngle {
startAngle += math.Pi * 2.0
}
}
startX := cx + math.Cos(startAngle)*rx
startY := cy + math.Sin(startAngle)*ry
c.MoveTo(startX, startY)
c.x, c.y = arc(c.converter, cx, cy, rx, ry, startAngle, angle, c.ApproximationScale)
if c.startX == c.x && c.startY == c.y {
c.converter.NextCommand(VertexCloseCommand)
}
c.converter.Vertex(c.x, c.y)
return c
}
func (c *PathConverter) RArcTo(dcx, dcy, rx, ry, startAngle, angle float64) *PathConverter {
c.ArcTo(c.x+dcx, c.y+dcy, rx, ry, startAngle, angle)
return c
}
func (c *PathConverter) Close() *PathConverter {
c.converter.NextCommand(VertexCloseCommand)
c.converter.Vertex(c.startX, c.startY)
return c
}
|
