From 500caaeda74dd9c660279036293f4b2997cf0b03 Mon Sep 17 00:00:00 2001 From: Dimitri Sokolyuk Date: Sat, 9 Sep 2017 09:42:37 +0200 Subject: Add vendor --- .../llgcode/draw2d/draw2dbase/stroker.go | 90 ++++++++++++++++++++++ 1 file changed, 90 insertions(+) create mode 100644 vendor/github.com/llgcode/draw2d/draw2dbase/stroker.go (limited to 'vendor/github.com/llgcode/draw2d/draw2dbase/stroker.go') diff --git a/vendor/github.com/llgcode/draw2d/draw2dbase/stroker.go b/vendor/github.com/llgcode/draw2d/draw2dbase/stroker.go new file mode 100644 index 0000000..640b228 --- /dev/null +++ b/vendor/github.com/llgcode/draw2d/draw2dbase/stroker.go @@ -0,0 +1,90 @@ +// Copyright 2010 The draw2d Authors. All rights reserved. +// created: 13/12/2010 by Laurent Le Goff + +package draw2dbase + +import ( + "math" + + "github.com/llgcode/draw2d" +) + +type LineStroker struct { + Flattener Flattener + HalfLineWidth float64 + Cap draw2d.LineCap + Join draw2d.LineJoin + vertices []float64 + rewind []float64 + x, y, nx, ny float64 +} + +func NewLineStroker(c draw2d.LineCap, j draw2d.LineJoin, flattener Flattener) *LineStroker { + l := new(LineStroker) + l.Flattener = flattener + l.HalfLineWidth = 0.5 + l.Cap = c + l.Join = j + return l +} + +func (l *LineStroker) MoveTo(x, y float64) { + l.x, l.y = x, y +} + +func (l *LineStroker) LineTo(x, y float64) { + l.line(l.x, l.y, x, y) +} + +func (l *LineStroker) LineJoin() { + +} + +func (l *LineStroker) line(x1, y1, x2, y2 float64) { + dx := (x2 - x1) + dy := (y2 - y1) + d := vectorDistance(dx, dy) + if d != 0 { + nx := dy * l.HalfLineWidth / d + ny := -(dx * l.HalfLineWidth / d) + l.appendVertex(x1+nx, y1+ny, x2+nx, y2+ny, x1-nx, y1-ny, x2-nx, y2-ny) + l.x, l.y, l.nx, l.ny = x2, y2, nx, ny + } +} + +func (l *LineStroker) Close() { + if len(l.vertices) > 1 { + l.appendVertex(l.vertices[0], l.vertices[1], l.rewind[0], l.rewind[1]) + } +} + +func (l *LineStroker) End() { + if len(l.vertices) > 1 { + l.Flattener.MoveTo(l.vertices[0], l.vertices[1]) + for i, j := 2, 3; j < len(l.vertices); i, j = i+2, j+2 { + l.Flattener.LineTo(l.vertices[i], l.vertices[j]) + } + } + for i, j := len(l.rewind)-2, len(l.rewind)-1; j > 0; i, j = i-2, j-2 { + l.Flattener.LineTo(l.rewind[i], l.rewind[j]) + } + if len(l.vertices) > 1 { + l.Flattener.LineTo(l.vertices[0], l.vertices[1]) + } + l.Flattener.End() + // reinit vertices + l.vertices = l.vertices[0:0] + l.rewind = l.rewind[0:0] + l.x, l.y, l.nx, l.ny = 0, 0, 0, 0 + +} + +func (l *LineStroker) appendVertex(vertices ...float64) { + s := len(vertices) / 2 + l.vertices = append(l.vertices, vertices[:s]...) + l.rewind = append(l.rewind, vertices[s:]...) +} + +func vectorDistance(dx, dy float64) float64 { + return float64(math.Sqrt(dx*dx + dy*dy)) +} -- cgit v1.2.3