sumi/main.go

package main

import (
	"fmt"
	"log"
	"math"
	"math/rand"
	"os"
	"time"

	"github.com/gen2brain/raylib-go/raylib"
	"github.com/ojrac/opensimplex-go"
)

const (
	screenWidth  = 1400
	screenHeight = 700
	displayScale = 2
	snapshotsDir = "snapshots"
)

func main() {

	os.MkdirAll(snapshotsDir, 0755)

	//rng := rand.New(rand.NewSource(0))

	log := log.New(os.Stdout, "", log.Ldate|log.Ltime|log.Lshortfile)

	storage, err := NewStorage(snapshotsDir)
	if err != nil {
		log.Printf("Error loading storage: %v\n", err)
		os.Exit(1)
	}

	rl.SetConfigFlags(rl.FlagWindowHighdpi)
	rl.InitWindow(screenWidth, screenHeight, "sumi sierpinski arrow")

	log.Printf("screen=%dx%d render=%dx%d",
		rl.GetScreenWidth(), rl.GetScreenHeight(),
		rl.GetRenderWidth(), rl.GetRenderHeight(),
	)

	w := rl.GetRenderWidth()
	h := rl.GetRenderHeight()

	var camera = rl.Camera2D{
		Target:   rl.Vector2{X: 0, Y: 0},
		Offset:   rl.Vector2{X: float32(w) / 2, Y: float32(h) / 2},
		Rotation: 0,
		Zoom:     1.0,
	}

	field :=
		ScaleField {
			Scale: 100.0,
			Field: &SimplexNoiseField {
				Noise: opensimplex.NewNormalized32(0),
			},
		}

	rng := rand.New(rand.NewSource(0))

	contourSketch := NewContourSketch(rng, &field)

	sketches := []Sketch {
		//&FieldSketch { Field: &field },
		&contourSketch,
	}

	rl.SetTargetFPS(60)

	t0 := time.Now()

	ports := MakePorts()

	ports["sierpinskiArrowAngle"] = Sine{
		Amp:  120,
		Bias: 100,
		Freq: 0.1,
	}

	for !rl.WindowShouldClose() {
		updateCamera(&camera)

		// begin drawing
		rl.BeginDrawing()
		//rl.ClearBackground(rl.Black)
		rl.BeginMode2D(camera)

		t := time.Since(t0).Seconds()

		// set up RenderCtx
		renderCtx := &RenderCtx{
			Width:  int32(w),
			Height: int32(h),
			Time:   t,
			Ports:  ports.Eval(t),
			Cam:    camera,
		}

		/**
		MAIN DRAWING
		 **/

		for _, s := range sketches {
			rl.PushMatrix()
			s.Draw(renderCtx)
			rl.PopMatrix()
		}

		if rl.IsKeyDown(rl.KeySpace) {
			if _, err := storage.Save(); err != nil {
				log.Printf("Error saving snapshot: %v\n", err)
			}
		}

		rl.EndMode2D()

		// HUD
		rl.DrawText("Mouse right button drag to move, mouse wheel to zoom", 10, 10, 20, rl.Black)
		rl.EndDrawing()
	}

	rl.CloseWindow()
}

type FieldSketch struct {
	Field Field
}

func (s *FieldSketch) Draw(ctx *RenderCtx) {
	fmt.Printf("drawing field")
	for x := range ctx.Width {
		for y := range ctx.Height {
			//screen := rl.Vector2 { X: float32(x) - float32(ctx.Width) / 2.0, Y: float32(y) - float32(ctx.Height) / 2.0 }
			screen := rl.Vector2 { X: float32(x), Y: float32(y) }
			world := rl.GetScreenToWorld2D(screen, ctx.Cam)
			//fmt.Printf("screen -> %v, world -> %v\n", screen, world)
			v := s.Field.Get(world.X, world.Y)
			//fmt.Printf("%.3f\n", v)
			clr := GrayCurve(v, 1.0)
			rl.DrawPixelV(world, clr)
		}
	}
}

type ContourSketch struct {
	field Field
	actors []*Actor
}

func NewContourSketch(rng *rand.Rand, field Field) ContourSketch {

	actors := make([]*Actor, 10000)
	for i := range len(actors) {
		actors[i] = 
			&Actor {
				position: RandRadialVec(rng, 0, 500, 0, 360),
				field: field,
			}
	}

	return ContourSketch {
		actors: actors,
	}
}

func (s *ContourSketch) Draw(ctx *RenderCtx) {
	for _, actor := range s.actors {
		actor.Draw()
	}
}


type Actor struct {
	position rl.Vector2
	field Field
}

func (a *Actor) Draw() {
	v := a.field.Get(a.position.X, a.position.Y)
	rad := rl.Remap(v, 0, 1, 0, 2 * math.Pi)
	stepSize := float32(2.0)
	nextPosition := rl.Vector2 { X: a.position.X + stepSize*float32(math.Cos(float64(rad))), Y: a.position.Y + stepSize*float32(math.Sin(float64(rad))) }
	rl.DrawLineV(a.position, nextPosition, rl.NewColor(255, 255, 255, 25))
	//fmt.Printf("position %v -> nextPosition %v \n", a.position, nextPosition)
	a.position = nextPosition
}


func RandRadialVec(rng *rand.Rand, minRadius float32, maxRadius float32, loAngle float32, hiAngle float32) rl.Vector2 {
	r := float64(rl.Remap(rng.Float32(), 0, 1, minRadius, maxRadius))
	deg := float64(rl.Remap(rng.Float32(), 0, 1, loAngle, hiAngle))
	rad := rl.Deg2rad * deg
	return rl.Vector2 { X: float32(r * math.Cos(rad)), Y: float32(r * math.Sin(rad)) }
}

func updateCamera(camera *rl.Camera2D) {
	// Get the world point that is under the mouse
	mouseVec2 := rl.GetMousePosition()

	if rl.IsMouseButtonDown(rl.MouseRightButton) {
		// get mouse delta from last frame
		delta := rl.GetMouseDelta()
		// compute the amount to move scaled by the camera zoom
		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 {
		mouseWorldPos := rl.GetScreenToWorld2D(mouseVec2, *camera)

		// Set the offset to where the mouse is
		camera.Offset = mouseVec2

		// Set the target to match, so that the camera maps the world space point
		// under the cursor to the screen space point under the cursor at any zoom
		camera.Target = mouseWorldPos

		// Zoom increment
		const zoomIncrement float32 = 0.125

		camera.Zoom += (wheel * zoomIncrement)
		if camera.Zoom < zoomIncrement {
			camera.Zoom = zoomIncrement
		}
	}
}

type Worm struct {
	position rl.Vector2
	angles []float32
	angleIndex int
	stepSize int
	renderPct float32
}

func (w *Worm) Draw(ctx *RenderCtx) {
	rl.PushMatrix()
	rl.Translatef(w.position.X, w.position.Y, 0)
	lastAngle := float32(0.0)
	stepCount := 0
	nudged := false
	for i := range w.angles {
		ii := (i + w.angleIndex) % len(w.angles)
		angle := w.angles[ii]
		deltaAngle := angle - lastAngle
		if !nudged {
			rad := float64(deltaAngle * math.Pi / 180.0)
			nudge := rl.Vector2 { X: float32(w.stepSize) * float32(math.Cos(rad)), Y: float32(w.stepSize) * float32(math.Sin(rad)) }
			w.position = rl.Vector2Add(w.position, nudge)
			nudged = true
		}
		rl.Rotatef(deltaAngle, 0, 0, 1)
		rl.DrawLine(0, 0, int32(w.stepSize), 0, rl.NewColor(184, 187, 38, 50))
		rl.Translatef(float32(w.stepSize), 0, 0)
		lastAngle = angle
		stepCount++
		if stepCount > int(float32(len(w.angles))*w.renderPct) {
			break
		}
	}
	rl.PopMatrix()
	w.angleIndex = (w.angleIndex + 1) % len(w.angles)
}

type SierpinskiArrow struct{}

func (s *SierpinskiArrow) Draw(ctx *RenderCtx) {
	sierpinskiArrow(ctx, int(ctx.Ports["sierpinskiArrowDepth"]), ctx.Ports["sierpinskiArrowLength"])
}

func sierpinskiArrow(ctx *RenderCtx, order int, length float64) {
	if order == 0 {
		curve(ctx, order, length, ctx.Ports["sierpinskiArrowAngle"])
	} else {
		rl.Rotatef(float32(ctx.Ports["sierpinskiArrowAngle"]), 0, 0, 1)
		curve(ctx, order, length, -ctx.Ports["sierpinskiArrowAngle"])
	}
}

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(length), 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 / 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)
		fmt.Printf("%.3f", angle)
		rl.EndMode2D()
	}
}