127 lines
3 KiB
Go
127 lines
3 KiB
Go
// Copyright 2010 The draw2d Authors. All rights reserved.
|
|
// created: 06/12/2010 by Laurent Le Goff
|
|
|
|
package draw2dbase
|
|
|
|
import (
|
|
"git.fromouter.space/crunchy-rocks/draw2d"
|
|
)
|
|
|
|
// Liner receive segment definition
|
|
type Liner interface {
|
|
// LineTo Draw a line from the current position to the point (x, y)
|
|
LineTo(x, y float64)
|
|
}
|
|
|
|
// Flattener receive segment definition
|
|
type Flattener interface {
|
|
// MoveTo Start a New line from the point (x, y)
|
|
MoveTo(x, y float64)
|
|
// LineTo Draw a line from the current position to the point (x, y)
|
|
LineTo(x, y float64)
|
|
// LineJoin use Round, Bevel or miter to join points
|
|
LineJoin()
|
|
// Close add the most recent starting point to close the path to create a polygon
|
|
Close()
|
|
// End mark the current line as finished so we can draw caps
|
|
End()
|
|
}
|
|
|
|
// Flatten convert curves into straight segments keeping join segments info
|
|
func Flatten(path *draw2d.Path, flattener Flattener, scale float64) {
|
|
// First Point
|
|
var startX, startY float64 = 0, 0
|
|
// Current Point
|
|
var x, y float64 = 0, 0
|
|
i := 0
|
|
for _, cmp := range path.Components {
|
|
switch cmp {
|
|
case draw2d.MoveToCmp:
|
|
x, y = path.Points[i], path.Points[i+1]
|
|
startX, startY = x, y
|
|
if i != 0 {
|
|
flattener.End()
|
|
}
|
|
flattener.MoveTo(x, y)
|
|
i += 2
|
|
case draw2d.LineToCmp:
|
|
x, y = path.Points[i], path.Points[i+1]
|
|
flattener.LineTo(x, y)
|
|
flattener.LineJoin()
|
|
i += 2
|
|
case draw2d.QuadCurveToCmp:
|
|
TraceQuad(flattener, path.Points[i-2:], 0.5)
|
|
x, y = path.Points[i+2], path.Points[i+3]
|
|
flattener.LineTo(x, y)
|
|
i += 4
|
|
case draw2d.CubicCurveToCmp:
|
|
TraceCubic(flattener, path.Points[i-2:], 0.5)
|
|
x, y = path.Points[i+4], path.Points[i+5]
|
|
flattener.LineTo(x, y)
|
|
i += 6
|
|
case draw2d.ArcToCmp:
|
|
x, y = TraceArc(flattener, path.Points[i], path.Points[i+1], path.Points[i+2], path.Points[i+3], path.Points[i+4], path.Points[i+5], scale)
|
|
flattener.LineTo(x, y)
|
|
i += 6
|
|
case draw2d.CloseCmp:
|
|
flattener.LineTo(startX, startY)
|
|
flattener.Close()
|
|
}
|
|
}
|
|
flattener.End()
|
|
}
|
|
|
|
// Transformer apply the Matrix transformation tr
|
|
type Transformer struct {
|
|
Tr draw2d.Matrix
|
|
Flattener Flattener
|
|
}
|
|
|
|
func (t Transformer) MoveTo(x, y float64) {
|
|
u := x*t.Tr[0] + y*t.Tr[2] + t.Tr[4]
|
|
v := x*t.Tr[1] + y*t.Tr[3] + t.Tr[5]
|
|
t.Flattener.MoveTo(u, v)
|
|
}
|
|
|
|
func (t Transformer) LineTo(x, y float64) {
|
|
u := x*t.Tr[0] + y*t.Tr[2] + t.Tr[4]
|
|
v := x*t.Tr[1] + y*t.Tr[3] + t.Tr[5]
|
|
t.Flattener.LineTo(u, v)
|
|
}
|
|
|
|
func (t Transformer) LineJoin() {
|
|
t.Flattener.LineJoin()
|
|
}
|
|
|
|
func (t Transformer) Close() {
|
|
t.Flattener.Close()
|
|
}
|
|
|
|
func (t Transformer) End() {
|
|
t.Flattener.End()
|
|
}
|
|
|
|
type SegmentedPath struct {
|
|
Points []float64
|
|
}
|
|
|
|
func (p *SegmentedPath) MoveTo(x, y float64) {
|
|
p.Points = append(p.Points, x, y)
|
|
// TODO need to mark this point as moveto
|
|
}
|
|
|
|
func (p *SegmentedPath) LineTo(x, y float64) {
|
|
p.Points = append(p.Points, x, y)
|
|
}
|
|
|
|
func (p *SegmentedPath) LineJoin() {
|
|
// TODO need to mark the current point as linejoin
|
|
}
|
|
|
|
func (p *SegmentedPath) Close() {
|
|
// TODO Close
|
|
}
|
|
|
|
func (p *SegmentedPath) End() {
|
|
// Nothing to do
|
|
}
|