automated snapshot

field.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	rl "github.com/gen2brain/raylib-go/raylib"
 	"github.com/ojrac/opensimplex-go"
 )
 
@@ -13,14 +14,23 @@ type Field interface {
 
 // TRANSFORM FIELDS
 type ScaleField struct {
-	Scale float32
 	Field Field
+	Scale float32
 }
 
 func (f *ScaleField) Get(x, y float32) float32 {
 	return f.Field.Get(x / f.Scale, y / f.Scale)
 }
 
+type TranslateField struct {
+	Field Field
+	x, y float32
+}
+
+func (f *TranslateField) Get(x, y float32) float32 {
+	return f.Field.Get(x + f.x, y + f.y)
+}
+
 // NOISE FIELDS
 
 type SimplexNoiseField struct {
@@ -31,3 +41,41 @@ func (f *SimplexNoiseField) Get(x, y float32) float32 {
 	return f.Noise.Eval2(x, y)
 }
 
+// IMAGE FIELDS
+
+type ImageField struct {
+	image *rl.Image
+	pixels ImagePixels
+}
+
+type ImagePixels struct {
+	w, h int
+	colors []rl.Color
+}
+
+func (p *ImagePixels) Get(x, y int) rl.Color {
+	if x < 0 || x >= p.w {
+		return rl.Black
+	}
+	if y < 0 || y >= p.h {
+		return rl.Black
+	}
+	return p.colors[x + y * p.w]
+}
+
+func NewImageField(path string) ImageField {
+	image := rl.LoadImage(path)
+	colors := rl.LoadImageColors(image)
+	pixels := ImagePixels {
+		w: int(image.Width),
+		h: int(image.Height),
+		colors: colors,
+	}
+	return ImageField { image: image, pixels: pixels }
+}
+
+func (f *ImageField) Get(x, y float32) float32 {
+	// todo : blend colors
+	c := f.pixels.Get(int(x), int(y))
+	return Brightness(c)
+}

main.go

@@ -13,8 +13,8 @@ import (
 )
 
 const (
-	screenWidth  = 1400
+	screenWidth  = 1200
-	screenHeight = 700
+	screenHeight = 900
 	displayScale = 2
 	snapshotsDir = "snapshots"
 )
@@ -49,20 +49,34 @@ func main() {
 		Zoom:     1.0,
 	}
 
+	/*
 	field :=
 		ScaleField {
-			Scale: 10.0,
+			Scale: 50.0,
 			Field: &SimplexNoiseField {
 				Noise: opensimplex.NewNormalized32(0),
 			},
 		}
+	*/
+
+	imgf := NewImageField("aphrodite.jpeg")
+	imageField :=
+		TranslateField {
+			x: float32(w) / 2.0,
+			y: float32(h) / 2.0,
+			//x: 5, y: 5,
+			Field: &ScaleField {
+				Scale: 4.5,
+				Field: &imgf,
+			},
+		}
 
 	rng := rand.New(rand.NewSource(0))
 
-	contourSketch := NewContourSketch(rng, &field)
+	contourSketch := NewContourSketch(rng, &imageField)
 
 	sketches := []Sketch {
-		//&FieldSketch { Field: &field },
+		//&FieldSketch { Field: &imageField },
 		&contourSketch,
 	}
 
@@ -156,7 +170,7 @@ func NewContourSketch(rng *rand.Rand, field Field) ContourSketch {
 				position: RandRadialVec(rng, 0, 500, 0, 360),
 				field: field,
 				stepSize: 0.5,
-				color: rl.NewColor(11, 35, 176, 200),
+				color: rl.NewColor(11, 35, 176, 170),
 			}
 	}
 

utils.go

@@ -21,4 +21,10 @@ func GrayCurve(v, k float32) rl.Color {
 	return rl.Color{R: c, G: c, B: c, A: 255}
 }
 
+func Brightness(c rl.Color) float32 {
+	r := float32(c.R) / 255
+	g := float32(c.G) / 255
+	b := float32(c.B) / 255
+	return 0.2126*r + 0.7152*g + 0.0722*b
+}