func TestGraphicGrobs(t *testing.T) {
// Output
file, err := os.Create("grobs.png")
if err != nil {
t.Fatalf("%", err)
}
pngCanvas := vgimg.PngCanvas{Canvas: vgimg.New(10*vg.Inch, 8*vg.Inch)}
vg.Initialize(pngCanvas)
pngCanvas.Translate(-5*vg.Inch, -4*vg.Inch)
dot := func(x, y float64) {
pngCanvas.Push()
pngCanvas.SetColor(BuiltinColors["red"])
pngCanvas.SetLineWidth(5)
var p vg.Path
xr := vg.Length(x) * vg.Inch
yr := vg.Length(y) * vg.Inch
p.Move(xr-5, yr-5)
p.Line(xr-5, yr+5)
p.Line(xr+5, yr+5)
p.Line(xr+5, yr-5)
p.Close()
pngCanvas.Fill(p)
pngCanvas.Pop()
}
dot(0, 0)
dot(5, 0)
dot(0, 4)
allVP := Viewport{
X0: 0,
Y0: 0,
Width: 10 * vg.Inch,
Height: 8 * vg.Inch,
Canvas: pngCanvas,
}
innerVP := allVP.Sub(0.05, 0.05, 0.9, 0.9)
bg := GrobRect{xmin: 0, ymin: 0, xmax: 1, ymax: 1, fill: BuiltinColors["gray80"]}
bg.Draw(innerVP)
cols := []string{"red", "green", "blue", "cyan", "magenta", "yellow",
"white", "gray", "black"}
// Draw points in all shapes, three sizes and all builtin colors.
points := []Grob{}
x, y := 0.1, 0.1
for shape := DotPoint; shape <= StarPoint; shape++ {
for size := 2; size < 7; size += 2 {
y = 0.05
for _, col := range cols {
g := GrobPoint{
x: x,
y: y,
size: float64(size),
shape: shape,
color: BuiltinColors[col],
}
points = append(points, g)
y += 0.035
}
x += 0.021
}
}
x, y = 0.02, 0.05
for _, col := range cols {
g := GrobText{
x: x,
y: y,
text: col,
size: 10,
color: BuiltinColors[col],
vjust: 0.5,
hjust: 0,
}
points = append(points, g)
y += 0.035
}
x, y = 0.121, 0.36
for shape := DotPoint; shape <= StarPoint; shape++ {
dy := float64(shape%2) * 0.015
g := GrobText{
x: x,
y: y + dy,
text: shape.String(),
size: 10,
color: BuiltinColors["black"],
vjust: 0.5,
hjust: 0.5,
}
points = append(points, g)
x += 3 * 0.021
}
for _, grob := range points {
grob.Draw(innerVP)
}
// Draw lines with different styles and widths.
lines := []Grob{}
x, y = 0.1, 0.45
for lt := SolidLine; lt <= TwodashLine; lt++ {
x = 0.1
for size := 1; size < 8; size += 2 {
g := GrobLine{
x0: x,
y0: y,
x1: x + 0.18,
y1: y,
size: float64(size),
linetype: lt,
color: BuiltinColors["black"],
}
lines = append(lines, g)
x += 0.22
}
y += 0.04
}
for _, grob := range lines {
grob.Draw(innerVP)
}
// Draw rectangles
rectVP := innerVP.Sub(0.1, 0.7, 0.4, 0.3)
rect := []Grob{}
bgr := GrobRect{xmin: 0, ymin: 0, xmax: 1, ymax: 1, fill: BuiltinColors["gray40"]}
bgr.Draw(rectVP)
x, y = 0.0, 0.0
w, h := 0.5, 0.5
for _, col := range cols {
g := GrobRect{
xmin: x,
ymin: y,
xmax: x + w,
ymax: y + h,
fill: BuiltinColors[col],
}
rect = append(rect, g)
x += w
y += h
w /= 2
h /= 2
}
for _, grob := range rect {
grob.Draw(rectVP)
}
// Draw path
pathVP := innerVP.Sub(0.55, 0.7, 0.4, 0.3)
bgp := GrobRect{xmin: 0, ymin: 0, xmax: 1, ymax: 1, fill: BuiltinColors["gray"]}
bgp.Draw(pathVP)
sin := make([]struct{ x, y float64 }, 50)
for i := range sin {
k := float64(i) / float64(len(sin)-1)
x = k * 2 * math.Pi
println(float64(i)/float64(len(sin)), x, math.Sin(x))
y = 0.4 * math.Sin(x)
sin[i].x = k
sin[i].y = 0.55 + y
}
g := GrobPath{
points: sin,
size: 4,
linetype: SolidLine,
color: BuiltinColors["white"],
}
g.Draw(pathVP)
cos := make([]struct{ x, y float64 }, 25)
for i := range cos {
k := float64(i) / float64(len(cos)-1)
x = k * 4 * math.Pi
y = 0.3 * math.Cos(x)
cos[i].x = k
cos[i].y = 0.45 + y
}
g = GrobPath{
points: cos,
size: 2,
linetype: DottedLine,
color: BuiltinColors["green"],
}
g.Draw(pathVP)
pngCanvas.WriteTo(file)
file.Close()
}
