automated snapshot

internal/graphics/graphics.go

@@ -0,0 +1,62 @@
+package graphics
+
+import (
+	"math/rand"
+	rl "github.com/gen2brain/raylib-go/raylib"
+)
+
+var (
+	FlourescentHues = []float32{
+		0,   // hot magenta-red
+		30,  // neon orange
+		60,  // acid yellow
+		120, // laser green
+		180, // cyan
+		210, // electric blue
+		270, // ultraviolet purple
+	}
+	FlourescentColors = makeFlourescentColors()
+)
+
+func makeFlourescentColors() []rl.Color {
+	fc := make([]rl.Color, len(FlourescentHues))
+	for i, hue := range(FlourescentHues) {
+		fc[i] = rl.ColorFromHSV(hue, 1.0, 1.0)
+	}
+	return fc
+}
+
+type ColorCycle interface {
+	Next() rl.Color
+}
+
+type ArrayBackedColorCycle struct {
+	colors []rl.Color
+	index int
+}
+
+func NewFixedColorCycle(colors []rl.Color) ArrayBackedColorCycle {
+	return ArrayBackedColorCycle {
+		colors: colors,
+		index: 0,
+	}
+}
+
+func (c ArrayBackedColorCycle) Shuffle(seed int64) ColorCycle {
+	r := rand.New(rand.NewSource(seed))
+	cprime := &ArrayBackedColorCycle {
+		colors: make([]rl.Color, len(c.colors)),
+		index: 0,
+	}
+	r.Shuffle(len(c.colors), func(i, j int) {
+		cprime.colors[i] = c.colors[j]
+	})
+	return cprime
+}
+
+func (c *ArrayBackedColorCycle) Next() rl.Color {
+	color := c.colors[c.index]
+	c.index = (c.index + 1) % len(c.colors)
+	return color
+}
+