329 lines
9.7 KiB
Go
329 lines
9.7 KiB
Go
// Copyright 2010 The draw2d Authors. All rights reserved.
|
|
// created: 21/11/2010 by Laurent Le Goff
|
|
|
|
// Package geometry draws some geometric tests.
|
|
package geometry
|
|
|
|
import (
|
|
"image"
|
|
"image/color"
|
|
"math"
|
|
|
|
"gopkg.in/llgcode/draw2d.v1"
|
|
"gopkg.in/llgcode/draw2d.v1/samples"
|
|
"gopkg.in/llgcode/draw2d.v1/samples/gopher2"
|
|
)
|
|
|
|
// Main draws geometry and returns the filename. This should only be
|
|
// used during testing.
|
|
func Main(gc draw2d.GraphicContext, ext string) (string, error) {
|
|
// Draw the droid
|
|
Draw(gc, 297, 210)
|
|
|
|
// Return the output filename
|
|
return samples.Output("geometry", ext), nil
|
|
}
|
|
|
|
// Bubble draws a text balloon.
|
|
func Bubble(gc draw2d.GraphicContext, x, y, width, height float64) {
|
|
sx, sy := width/100, height/100
|
|
gc.MoveTo(x+sx*50, y)
|
|
gc.QuadCurveTo(x, y, x, y+sy*37.5)
|
|
gc.QuadCurveTo(x, y+sy*75, x+sx*25, y+sy*75)
|
|
gc.QuadCurveTo(x+sx*25, y+sy*95, x+sx*5, y+sy*100)
|
|
gc.QuadCurveTo(x+sx*35, y+sy*95, x+sx*40, y+sy*75)
|
|
gc.QuadCurveTo(x+sx*100, y+sy*75, x+sx*100, y+sy*37.5)
|
|
gc.QuadCurveTo(x+sx*100, y, x+sx*50, y)
|
|
gc.Stroke()
|
|
}
|
|
|
|
// CurveRectangle draws a rectangle with bezier curves (not rounded rectangle).
|
|
func CurveRectangle(gc draw2d.GraphicContext, x0, y0,
|
|
rectWidth, rectHeight float64, stroke, fill color.Color) {
|
|
radius := (rectWidth + rectHeight) / 4
|
|
|
|
x1 := x0 + rectWidth
|
|
y1 := y0 + rectHeight
|
|
if rectWidth/2 < radius {
|
|
if rectHeight/2 < radius {
|
|
gc.MoveTo(x0, (y0+y1)/2)
|
|
gc.CubicCurveTo(x0, y0, x0, y0, (x0+x1)/2, y0)
|
|
gc.CubicCurveTo(x1, y0, x1, y0, x1, (y0+y1)/2)
|
|
gc.CubicCurveTo(x1, y1, x1, y1, (x1+x0)/2, y1)
|
|
gc.CubicCurveTo(x0, y1, x0, y1, x0, (y0+y1)/2)
|
|
} else {
|
|
gc.MoveTo(x0, y0+radius)
|
|
gc.CubicCurveTo(x0, y0, x0, y0, (x0+x1)/2, y0)
|
|
gc.CubicCurveTo(x1, y0, x1, y0, x1, y0+radius)
|
|
gc.LineTo(x1, y1-radius)
|
|
gc.CubicCurveTo(x1, y1, x1, y1, (x1+x0)/2, y1)
|
|
gc.CubicCurveTo(x0, y1, x0, y1, x0, y1-radius)
|
|
}
|
|
} else {
|
|
if rectHeight/2 < radius {
|
|
gc.MoveTo(x0, (y0+y1)/2)
|
|
gc.CubicCurveTo(x0, y0, x0, y0, x0+radius, y0)
|
|
gc.LineTo(x1-radius, y0)
|
|
gc.CubicCurveTo(x1, y0, x1, y0, x1, (y0+y1)/2)
|
|
gc.CubicCurveTo(x1, y1, x1, y1, x1-radius, y1)
|
|
gc.LineTo(x0+radius, y1)
|
|
gc.CubicCurveTo(x0, y1, x0, y1, x0, (y0+y1)/2)
|
|
} else {
|
|
gc.MoveTo(x0, y0+radius)
|
|
gc.CubicCurveTo(x0, y0, x0, y0, x0+radius, y0)
|
|
gc.LineTo(x1-radius, y0)
|
|
gc.CubicCurveTo(x1, y0, x1, y0, x1, y0+radius)
|
|
gc.LineTo(x1, y1-radius)
|
|
gc.CubicCurveTo(x1, y1, x1, y1, x1-radius, y1)
|
|
gc.LineTo(x0+radius, y1)
|
|
gc.CubicCurveTo(x0, y1, x0, y1, x0, y1-radius)
|
|
}
|
|
}
|
|
gc.Close()
|
|
gc.SetStrokeColor(stroke)
|
|
gc.SetFillColor(fill)
|
|
gc.SetLineWidth(10.0)
|
|
gc.FillStroke()
|
|
}
|
|
|
|
// Dash draws a line with a dash pattern
|
|
func Dash(gc draw2d.GraphicContext, x, y, width, height float64) {
|
|
sx, sy := width/162, height/205
|
|
gc.SetStrokeColor(image.Black)
|
|
gc.SetLineDash([]float64{height / 10, height / 50, height / 50, height / 50}, -50.0)
|
|
gc.SetLineCap(draw2d.ButtCap)
|
|
gc.SetLineJoin(draw2d.RoundJoin)
|
|
gc.SetLineWidth(height / 50)
|
|
|
|
gc.MoveTo(x+sx*60.0, y)
|
|
gc.LineTo(x+sx*60.0, y)
|
|
gc.LineTo(x+sx*162, y+sy*205)
|
|
gc.RLineTo(sx*-102.4, 0.0)
|
|
gc.CubicCurveTo(x+sx*-17, y+sy*205, x+sx*-17, y+sy*103, x+sx*60.0, y+sy*103.0)
|
|
gc.Stroke()
|
|
gc.SetLineDash(nil, 0.0)
|
|
}
|
|
|
|
// Arc draws an arc with a positive angle (clockwise)
|
|
func Arc(gc draw2d.GraphicContext, xc, yc, width, height float64) {
|
|
// draw an arc
|
|
xc += width / 2
|
|
yc += height / 2
|
|
radiusX, radiusY := width/2, height/2
|
|
startAngle := 45 * (math.Pi / 180.0) /* angles are specified */
|
|
angle := 135 * (math.Pi / 180.0) /* clockwise in radians */
|
|
gc.SetLineWidth(width / 10)
|
|
gc.SetLineCap(draw2d.ButtCap)
|
|
gc.SetStrokeColor(image.Black)
|
|
gc.MoveTo(xc+math.Cos(startAngle)*radiusX, yc+math.Sin(startAngle)*radiusY)
|
|
gc.ArcTo(xc, yc, radiusX, radiusY, startAngle, angle)
|
|
gc.Stroke()
|
|
|
|
// fill a circle
|
|
gc.SetStrokeColor(color.NRGBA{255, 0x33, 0x33, 0x80})
|
|
gc.SetFillColor(color.NRGBA{255, 0x33, 0x33, 0x80})
|
|
gc.SetLineWidth(width / 20)
|
|
|
|
gc.MoveTo(xc+math.Cos(startAngle)*radiusX, yc+math.Sin(startAngle)*radiusY)
|
|
gc.LineTo(xc, yc)
|
|
gc.LineTo(xc-radiusX, yc)
|
|
gc.Stroke()
|
|
|
|
gc.MoveTo(xc, yc)
|
|
gc.ArcTo(xc, yc, width/10.0, height/10.0, 0, 2*math.Pi)
|
|
gc.Fill()
|
|
}
|
|
|
|
// ArcNegative draws an arc with a negative angle (anti clockwise).
|
|
func ArcNegative(gc draw2d.GraphicContext, xc, yc, width, height float64) {
|
|
xc += width / 2
|
|
yc += height / 2
|
|
radiusX, radiusY := width/2, height/2
|
|
startAngle := 45.0 * (math.Pi / 180.0) /* angles are specified */
|
|
angle := -225 * (math.Pi / 180.0) /* clockwise in radians */
|
|
gc.SetLineWidth(width / 10)
|
|
gc.SetLineCap(draw2d.ButtCap)
|
|
gc.SetStrokeColor(image.Black)
|
|
|
|
gc.ArcTo(xc, yc, radiusX, radiusY, startAngle, angle)
|
|
gc.Stroke()
|
|
// fill a circle
|
|
gc.SetStrokeColor(color.NRGBA{255, 0x33, 0x33, 0x80})
|
|
gc.SetFillColor(color.NRGBA{255, 0x33, 0x33, 0x80})
|
|
gc.SetLineWidth(width / 20)
|
|
|
|
gc.MoveTo(xc+math.Cos(startAngle)*radiusX, yc+math.Sin(startAngle)*radiusY)
|
|
gc.LineTo(xc, yc)
|
|
gc.LineTo(xc-radiusX, yc)
|
|
gc.Stroke()
|
|
|
|
gc.ArcTo(xc, yc, width/10.0, height/10.0, 0, 2*math.Pi)
|
|
gc.Fill()
|
|
}
|
|
|
|
// CubicCurve draws a cubic curve with its control points.
|
|
func CubicCurve(gc draw2d.GraphicContext, x, y, width, height float64) {
|
|
sx, sy := width/162, height/205
|
|
x0, y0 := x, y+sy*100.0
|
|
x1, y1 := x+sx*75, y+sy*205
|
|
x2, y2 := x+sx*125, y
|
|
x3, y3 := x+sx*205, y+sy*100
|
|
|
|
gc.SetStrokeColor(image.Black)
|
|
gc.SetFillColor(color.NRGBA{0xAA, 0xAA, 0xAA, 0xFF})
|
|
gc.SetLineWidth(width / 10)
|
|
gc.MoveTo(x0, y0)
|
|
gc.CubicCurveTo(x1, y1, x2, y2, x3, y3)
|
|
gc.Stroke()
|
|
|
|
gc.SetStrokeColor(color.NRGBA{0xFF, 0x33, 0x33, 0x88})
|
|
|
|
gc.SetLineWidth(width / 20)
|
|
// draw segment of curve
|
|
gc.MoveTo(x0, y0)
|
|
gc.LineTo(x1, y1)
|
|
gc.LineTo(x2, y2)
|
|
gc.LineTo(x3, y3)
|
|
gc.Stroke()
|
|
}
|
|
|
|
// FillString draws a filled and stroked string.
|
|
func FillString(gc draw2d.GraphicContext, x, y, width, height float64) {
|
|
sx, sy := width/100, height/100
|
|
gc.Save()
|
|
gc.SetStrokeColor(image.Black)
|
|
gc.SetLineWidth(1)
|
|
draw2d.RoundRect(gc, x+sx*5, y+sy*5, x+sx*95, y+sy*95, sx*10, sy*10)
|
|
gc.FillStroke()
|
|
gc.SetFillColor(image.Black)
|
|
gc.SetFontSize(height / 6)
|
|
gc.Translate(x+sx*6, y+sy*52)
|
|
gc.SetFontData(draw2d.FontData{
|
|
Name: "luxi",
|
|
Family: draw2d.FontFamilyMono,
|
|
Style: draw2d.FontStyleBold | draw2d.FontStyleItalic})
|
|
w := gc.FillString("Hug")
|
|
gc.Translate(w+sx, 0)
|
|
left, top, right, bottom := gc.GetStringBounds("cou")
|
|
gc.SetStrokeColor(color.NRGBA{255, 0x33, 0x33, 0x80})
|
|
draw2d.Rect(gc, left, top, right, bottom)
|
|
gc.SetLineWidth(height / 50)
|
|
gc.Stroke()
|
|
gc.SetFillColor(color.NRGBA{0x33, 0x33, 0xff, 0xff})
|
|
gc.SetStrokeColor(color.NRGBA{0x33, 0x33, 0xff, 0xff})
|
|
gc.SetLineWidth(height / 100)
|
|
gc.StrokeString("Hug")
|
|
gc.Restore()
|
|
}
|
|
|
|
// FillStroke first fills and afterwards strokes a path.
|
|
func FillStroke(gc draw2d.GraphicContext, x, y, width, height float64) {
|
|
sx, sy := width/210, height/215
|
|
gc.MoveTo(x+sx*113.0, y)
|
|
gc.LineTo(x+sx*215.0, y+sy*215)
|
|
gc.RLineTo(sx*-100, 0)
|
|
gc.CubicCurveTo(x+sx*35, y+sy*215, x+sx*35, y+sy*113, x+sx*113.0, y+sy*113)
|
|
gc.Close()
|
|
|
|
gc.MoveTo(x+sx*50.0, y)
|
|
gc.RLineTo(sx*51.2, sy*51.2)
|
|
gc.RLineTo(sx*-51.2, sy*51.2)
|
|
gc.RLineTo(sx*-51.2, sy*-51.2)
|
|
gc.Close()
|
|
|
|
gc.SetLineWidth(width / 20.0)
|
|
gc.SetFillColor(color.NRGBA{0, 0, 0xFF, 0xFF})
|
|
gc.SetStrokeColor(image.Black)
|
|
gc.FillStroke()
|
|
}
|
|
|
|
// FillStyle demonstrates the difference between even odd and non zero winding rule.
|
|
func FillStyle(gc draw2d.GraphicContext, x, y, width, height float64) {
|
|
sx, sy := width/232, height/220
|
|
gc.SetLineWidth(width / 40)
|
|
|
|
draw2d.Rect(gc, x+sx*0, y+sy*12, x+sx*232, y+sy*70)
|
|
|
|
wheel1 := new(draw2d.PathStorage)
|
|
wheel1.ArcTo(x+sx*52, y+sy*70, sx*40, sy*40, 0, 2*math.Pi)
|
|
wheel2 := new(draw2d.PathStorage)
|
|
wheel2.ArcTo(x+sx*180, y+sy*70, sx*40, sy*40, 0, -2*math.Pi)
|
|
|
|
gc.SetFillRule(draw2d.FillRuleEvenOdd)
|
|
gc.SetFillColor(color.NRGBA{0, 0xB2, 0, 0xFF})
|
|
|
|
gc.SetStrokeColor(image.Black)
|
|
gc.FillStroke(wheel1, wheel2)
|
|
|
|
draw2d.Rect(gc, x, y+sy*140, x+sx*232, y+sy*198)
|
|
wheel1 = new(draw2d.PathStorage)
|
|
wheel1.ArcTo(x+sx*52, y+sy*198, sx*40, sy*40, 0, 2*math.Pi)
|
|
wheel2 = new(draw2d.PathStorage)
|
|
wheel2.ArcTo(x+sx*180, y+sy*198, sx*40, sy*40, 0, -2*math.Pi)
|
|
|
|
gc.SetFillRule(draw2d.FillRuleWinding)
|
|
gc.SetFillColor(color.NRGBA{0, 0, 0xE5, 0xFF})
|
|
gc.FillStroke(wheel1, wheel2)
|
|
}
|
|
|
|
// PathTransform scales a path differently in horizontal and vertical direction.
|
|
func PathTransform(gc draw2d.GraphicContext, x, y, width, height float64) {
|
|
gc.Save()
|
|
gc.SetLineWidth(width / 10)
|
|
gc.Translate(x+width/2, y+height/2)
|
|
gc.Scale(1, 4)
|
|
gc.ArcTo(0, 0, width/8, height/8, 0, math.Pi*2)
|
|
gc.Close()
|
|
gc.Stroke()
|
|
gc.Restore()
|
|
}
|
|
|
|
// Star draws many lines from a center.
|
|
func Star(gc draw2d.GraphicContext, x, y, width, height float64) {
|
|
gc.Save()
|
|
gc.Translate(x+width/2, y+height/2)
|
|
gc.SetLineWidth(width / 40)
|
|
for i := 0.0; i < 360; i = i + 10 { // Go from 0 to 360 degrees in 10 degree steps
|
|
gc.Save() // Keep rotations temporary
|
|
gc.Rotate(i * (math.Pi / 180.0)) // Rotate by degrees on stack from 'for'
|
|
gc.MoveTo(0, 0)
|
|
gc.LineTo(width/2, 0)
|
|
gc.Stroke()
|
|
gc.Restore()
|
|
}
|
|
gc.Restore()
|
|
}
|
|
|
|
// Draw all figures in a nice 4x3 grid.
|
|
func Draw(gc draw2d.GraphicContext, width, height float64) {
|
|
mx, my := width*0.025, height*0.025 // margin
|
|
dx, dy := (width-2*mx)/4, (height-2*my)/3
|
|
w, h := dx-2*mx, dy-2*my
|
|
x0, y := 2*mx, 2*my
|
|
x := x0
|
|
Bubble(gc, x, y, w, h)
|
|
x += dx
|
|
CurveRectangle(gc, x, y, w, h, color.NRGBA{0x80, 0, 0, 0x80}, color.NRGBA{0x80, 0x80, 0xFF, 0xFF})
|
|
x += dx
|
|
Dash(gc, x, y, w, h)
|
|
x += dx
|
|
Arc(gc, x, y, w, h)
|
|
x = x0
|
|
y += dy
|
|
ArcNegative(gc, x, y, w, h)
|
|
x += dx
|
|
CubicCurve(gc, x, y, w, h)
|
|
x += dx
|
|
FillString(gc, x, y, w, h)
|
|
x += dx
|
|
FillStroke(gc, x, y, w, h)
|
|
x = x0
|
|
y += dy
|
|
FillStyle(gc, x, y, w, h)
|
|
x += dx
|
|
PathTransform(gc, x, y, w, h)
|
|
x += dx
|
|
Star(gc, x, y, w, h)
|
|
x += dx
|
|
gopher2.Draw(gc, x, y, w, h/2)
|
|
}
|