func drawMoon(canvas gxui.Canvas, center math.Point, radius float32) {
c := 40
p := make(gxui.Polygon, c*2)
for i := 0; i < c; i++ {
frac := float32(i) / float32(c)
α := math.Lerpf(math.Pi*1.2, math.Pi*-0.2, frac)
p[i] = gxui.PolygonVertex{
Position: math.Point{
X: center.X + int(radius*math.Sinf(α)),
Y: center.Y + int(radius*math.Cosf(α)),
},
RoundedRadius: 0,
}
}
for i := 0; i < c; i++ {
frac := float32(i) / float32(c)
α := math.Lerpf(math.Pi*-0.2, math.Pi*1.2, frac)
r := math.Lerpf(radius, radius*0.5, math.Sinf(frac*math.Pi))
p[i+c] = gxui.PolygonVertex{
Position: math.Point{
X: center.X + int(r*math.Sinf(α)),
Y: center.Y + int(r*math.Cosf(α)),
},
RoundedRadius: 0,
}
}
canvas.DrawPolygon(p, gxui.CreatePen(3, gxui.Gray80), gxui.CreateBrush(gxui.Gray40))
}
func appMain(driver gxui.Driver) {
theme := flags.CreateTheme(driver)
font, err := driver.CreateFont(gxfont.Default, 75)
if err != nil {
panic(err)
}
window := theme.CreateWindow(380, 100, "Hi")
window.SetBackgroundBrush(gxui.CreateBrush(gxui.Gray50))
label := theme.CreateLabel()
label.SetFont(font)
label.SetText("Hello world")
window.AddChild(label)
ticker := time.NewTicker(time.Millisecond * 30)
go func() {
phase := float32(0)
for _ = range ticker.C {
c := gxui.Color{
R: 0.75 + 0.25*math.Cosf((phase+0.000)*math.TwoPi),
G: 0.75 + 0.25*math.Cosf((phase+0.333)*math.TwoPi),
B: 0.75 + 0.25*math.Cosf((phase+0.666)*math.TwoPi),
A: 0.50 + 0.50*math.Cosf(phase*10),
}
phase += 0.01
driver.Call(func() {
label.SetColor(c)
})
}
}()
window.OnClose(ticker.Stop)
window.OnClose(driver.Terminate)
}
func drawStar(canvas gxui.Canvas, center math.Point, radius, rotation float32, points int) {
p := make(gxui.Polygon, points*2)
for i := 0; i < points*2; i++ {
frac := float32(i) / float32(points*2)
α := frac*math.TwoPi + rotation
r := []float32{radius, radius / 2}[i&1]
p[i] = gxui.PolygonVertex{
Position: math.Point{
X: center.X + int(r*math.Cosf(α)),
Y: center.Y + int(r*math.Sinf(α)),
},
RoundedRadius: []float32{0, 50}[i&1],
}
}
canvas.DrawPolygon(p, gxui.CreatePen(3, gxui.Red), gxui.CreateBrush(gxui.Yellow))
}