automated snapshot

main.go

@@ -1,11 +1,14 @@
 package main
 
 import (
+	"fmt"
 	"log"
+	"math"
 	"os"
+	"time"
+
 	"github.com/gen2brain/raylib-go/raylib"
 	"github.com/ojrac/opensimplex-go"
-	"math"
 )
 
 func clamp01(v float64) float64 {
@@ -24,31 +27,6 @@ func GrayCurve(v, k float64) rl.Color {
 	return rl.Color{R: c, G: c, B: c, A: 255}
 }
 
-func sierpinskiArrow(order int, length float64) {
-	rl.Scalef(1, -1, 1)
-	//rl.Rotatef(180, 0, 0, 1)
-	if order == 0 {
-		curve(order, length, 60)
-	} else {
-		rl.Rotatef(60, 0, 0, 1)
-		curve(order, length, -60)
-	}
-}
-
-func curve(order int, length float64, angle float64) {
-	if order == 0 {
-		len := int32(length)
-		rl.DrawLine(0, 0, len, 0, rl.Black)
-		rl.Translatef(float32(len), 0, 0)
-	} else {
-		curve(order-1, length/2, -angle)
-		rl.Rotatef(float32(angle), 0, 0, 1)
-		curve(order-1, length/2, angle)
-		rl.Rotatef(float32(angle), 0, 0, 1)
-		curve(order-1, length/2, -angle)
-	}
-}
-
 func main() {
 
 	const (
@@ -69,6 +47,10 @@ func main() {
 
 	rl.InitWindow(screenWidth, screenHeight, "sumi sierpinski arrow")
 
+	sketches := []Sketch {
+		SierpinskiArrow{},
+	}
+
 	var camera = rl.Camera2D{
 		Target:   rl.Vector2{X: 0, Y: 0},
 		Offset:   rl.Vector2{X: float32(screenWidth) / 2, Y: float32(screenHeight) / 2},
@@ -78,29 +60,72 @@ func main() {
 
 	rl.SetTargetFPS(60)
 
-	angles := make([]float32, 1000)
-	noise := opensimplex.NewNormalized(0)
-	for i := range len(angles) {
-		angles[i] = float32(noise.Eval2(float64(i)*0.05, 0.00))*0.1 - 0.05
+	t0 := time.Now()
+
+	ports := MakePorts()
+	ports["sierpinskiArrowLength"] = Sine {
+		Amp: 1000.0,
+		Freq: 0.001,
 	}
 
-	frameNum := 0
+	ports["sierpinskiArrowDepth"] = Saw {
+		Min: 1, Max: 9, Period: 10,
+	}
 
 	for !rl.WindowShouldClose() {
+		updateCamera(&camera)
 
-		frameNum++
+		// begin drawing
+		rl.BeginDrawing()
+		rl.ClearBackground(rl.RayWhite)
+		rl.BeginMode2D(camera)
+		rl.PushMatrix()
 
+		t := time.Since(t0).Seconds()
+
+		// set up RenderCtx
+		renderCtx := &RenderCtx {
+			Width: screenWidth,
+			Height: screenHeight,
+			Time: t,
+			Ports: ports.Eval(t),
+		}
+
+		/**
+		MAIN DRAWING
+		 **/
+		for _, s := range sketches {
+			s.Draw(renderCtx)
+		}
+
+		if rl.IsKeyDown(rl.KeySpace) {
+			if _, err := storage.Save(); err != nil {
+				log.Printf("Error saving snapshot: %v\n", err)
+			}
+		}
+
+		rl.PopMatrix()
+		rl.EndMode2D()
+
+		// HUD
+		rl.DrawText("Mouse right button drag to move, mouse wheel to zoom", 10, 10, 20, rl.White)
+		rl.EndDrawing()
+	}
+
+	rl.CloseWindow()
+}
+
+func updateCamera(camera *rl.Camera2D) {
 	if rl.IsMouseButtonDown(rl.MouseRightButton) {
 		delta := rl.GetMouseDelta()
 		delta = rl.Vector2Scale(delta, -1.0/camera.Zoom)
 		camera.Target = rl.Vector2Add(camera.Target, delta)
 	}
-
 	// Zoom based on mouse wheel
 	wheel := rl.GetMouseWheelMove()
 	if wheel != 0 {
 		// Get the world point that is under the mouse
-			mouseWorldPos := rl.GetScreenToWorld2D(rl.GetMousePosition(), camera)
+		mouseWorldPos := rl.GetScreenToWorld2D(rl.GetMousePosition(), *camera)
 
 		// Set the offset to where the mouse is
 		camera.Offset = rl.GetMousePosition()
@@ -117,73 +142,66 @@ func main() {
 			camera.Zoom = zoomIncrement
 		}
 	}
+}
 
-		rl.BeginDrawing()
-		rl.ClearBackground(rl.RayWhite)
 
-		rl.BeginMode2D(camera)
 
+type SierpinskiArrow struct {}
+
+func (s SierpinskiArrow) Draw(ctx *RenderCtx) {
 	rl.PushMatrix()
+	sierpinskiArrow(ctx, int(ctx.Ports["sierpinskiArrowDepth"]), ctx.Ports["sierpinskiArrowLength"])
+	rl.PopMatrix()
+}
 
-		/**
-		for x := range screenWidth {
-			for y := range screenHeight {
-				sp := rl.Vector2 { X: float32(x), Y: float32(y) };
-				wp := rl.GetScreenToWorld2D(sp, camera);
-				normVal := noise.Eval2(float64(wp.X), float64(wp.Y))
-				rl.DrawPixelV(wp, GrayCurve(normVal, 0.8));
+func sierpinskiArrow(ctx *RenderCtx, order int, length float64) {
+	if order == 0 {
+		curve(ctx, order, length, 60)
+	} else {
+		rl.Rotatef(60, 0, 0, 1)
+		curve(ctx, order, length, -60)
 	}
+}
+
+func curve(ctx *RenderCtx, order int, length float64, angle float64) {
+	if order == 0 {
+		len := int32(length)
+		rl.DrawLine(0, 0, len, 0, rl.Black)
+		rl.Translatef(float32(len), 0, 0)
+	} else {
+		curve(ctx, order-1, length/2, -angle)
+		rl.Rotatef(float32(angle), 0, 0, 1)
+		curve(ctx, order-1, length/2, angle)
+		rl.Rotatef(float32(angle), 0, 0, 1)
+		curve(ctx, order-1, length/2, -angle)
 	}
-		**/
+}
+
+func main2() {
+	angles := make([]float32, 1000)
+	noise := opensimplex.NewNormalized(0)
+	for i := range len(angles) {
+		angles[i] = float32(noise.Eval2(float64(i)*0.05, 0.00))*0.1 - 0.05
+	}
+
+	frameNum := 0
+
+	for !rl.WindowShouldClose() {
+
+		frameNum++
 
 		// initial transform by halfway again through angle array
 
-		angleIndex := frameNum % len(angles)
+		angleIndex := (frameNum/10) % len(angles)
 		angle := angles[angleIndex]
 
 		initAngle := angles[(angleIndex+len(angles)/2)%len(angles)]
 		rl.Rotatef(2500*initAngle, 0, 0, 1)
 		rl.Translatef(100*initAngle, 100*initAngle, 0)
 
-		stepSize := int32(1)
-		for range 1000 {
-			rl.DrawLine(0, 0, stepSize, 0, rl.Black)
-			rl.Translatef(float32(stepSize), 0, 0)
-			rl.Rotatef(angle, 0, 0, 1)
-			angleIndex++
-			angleIndex = angleIndex % len(angles)
-			angle += angles[angleIndex]
-		}
-		rl.PopMatrix()
-
-		rl.PushMatrix()
-
-		//rl.Translatef(-screenWidth/2, screenHeight/2, 0)
-
-		sierpinskiArrow(9, 800)
-
-		rl.PopMatrix()
-
-		/*
-			rl.PushMatrix()
-			rl.Translatef(0, 25*50, 0)
-			rl.Rotatef(90, 1, 0, 0)
-			rl.DrawGrid(100, 50)
-			rl.PopMatrix()
-		*/
+		fmt.Printf("%.3f", angle)
 
 		rl.EndMode2D()
-
-		if rl.IsKeyDown(rl.KeySpace) {
-			if _, err := storage.Save(); err != nil {
-				log.Printf("Error saving snapshot: %v\n", err)
-			}
 	}
 
-		rl.DrawText("Mouse right button drag to move, mouse wheel to zoom", 10, 10, 20, rl.White)
-
-		rl.EndDrawing()
-	}
-
-	rl.CloseWindow()
 }

signals.go

@@ -0,0 +1,28 @@
+package main
+
+import (
+	"math"
+)
+
+type Signal interface {
+	Eval(t float64) float64
+}
+
+type Const struct{ V float64 }
+func (s Const) Eval(t float64) float64 { return s.V }
+
+type Sine struct {
+	Amp, Freq, Phase, Bias float64
+}
+func (s Sine) Eval(t float64) float64 {
+	return s.Bias + s.Amp*math.Sin(2*math.Pi*s.Freq*t+s.Phase)
+}
+
+type Saw struct {
+	Min, Max, Period float64
+}
+func (s Saw) Eval(t float64) float64 {
+	u := math.Mod(t, s.Period) / s.Period // 0..1
+	return s.Min + (s.Max-s.Min)*u
+}
+

sketch.go

@@ -0,0 +1,39 @@
+package main
+
+import (
+	"github.com/gen2brain/raylib-go/raylib"
+)
+
+type Sketch interface {
+	Draw(ctx *RenderCtx)
+}
+
+/** Ports **/
+
+type Ports map[string]Signal
+
+func MakePorts() Ports {
+	return make(Ports)
+}
+
+/**
+ * materialize current value for all ports
+ **/
+func (p Ports) Eval(t float64) map[string]float64 {
+	out := make(map[string]float64, len(p))
+	for name, sig := range(p) {
+		out[name] = sig.Eval(t)
+	}
+	return out
+}
+
+/** RenderCtx **/
+
+type RenderCtx struct {
+	Width int32
+	Height int32
+	Time float64
+	Ports map[string]float64
+	Cam rl.Camera2D
+}
+