Bookmark SDF rendered by Ebiten using gfx

ebiten-gfx-bookmark.go

package main

import (
	"github.com/hajimehoshi/ebiten"
	"github.com/peterhellberg/gfx"
)

type Game struct {
	gfx.Vec
	Image *gfx.Paletted
	N     int
}

func (g *Game) Update(screen *ebiten.Image) error {
	if ebiten.IsKeyPressed(ebiten.KeyEscape) || ebiten.IsKeyPressed(ebiten.KeyQ) {
		return gfx.ErrDone
	}

	v := g.Vec

	if ebiten.IsKeyPressed(ebiten.KeyLeft) {
		g.X += 0.1
	}

	if ebiten.IsKeyPressed(ebiten.KeyRight) {
		g.X -= 0.1
	}

	if ebiten.IsKeyPressed(ebiten.KeyUp) {
		g.Y += 0.1
	}

	if ebiten.IsKeyPressed(ebiten.KeyDown) {
		g.Y -= 0.1
	}

	n := g.N

	if ebiten.IsKeyPressed(ebiten.Key1) {
		g.N = 0
	}

	if ebiten.IsKeyPressed(ebiten.Key2) {
		g.N = 1
	}

	if ebiten.IsKeyPressed(ebiten.Key3) {
		g.N = 2
	}

	if ebiten.IsKeyPressed(ebiten.Key4) {
		g.N = 3
	}

	if ebiten.IsKeyPressed(ebiten.Key5) {
		g.N = 4
	}

	if ebiten.IsKeyPressed(ebiten.Key6) {
		g.N = 5
	}

	if ebiten.IsKeyPressed(ebiten.Key7) {
		g.N = 6
	}

	if ebiten.IsKeyPressed(ebiten.Key8) {
		g.N = 7
	}

	if ebiten.IsKeyPressed(ebiten.Key9) {
		g.N = 8
	}

	if !v.Eq(g.Vec) || v.Eq(gfx.ZV) || n != g.N {
		p := Palettes[g.N]

		m := gfx.NewPaletted(w, h, p, p[0])

		c := gfx.BoundsCenter(gfx.IR(0, 0, -w, -h))

		matrix := gfx.IM.Moved(c.Sub(gfx.V(0, -20)))

		gfx.EachPixel(m.Bounds(), func(x, y int) {
			pm := matrix.Project(gfx.IV(x, y))
			sd := gfx.SignedDistance{Vec: pm}

			d := g.shape(sd)

			switch {
			case d < 0:
				m.Set(x, y, p[1])
			case d < 1:
				m.Set(x, y, p[2])
			case d < 2:
				m.Set(x, y, p[3])
			}
		})

		g.Image = m
	}

	return nil
}

func (g *Game) Draw(screen *ebiten.Image) {
	screen.ReplacePixels(g.Image.Pixels())
}

func (g *Game) Layout(_, _ int) (int, int) {
	return 64, 64
}

func (g *Game) shape(sd gfx.SignedDistance) float64 {
	return sd.OpSubtraction(
		sd.OpSmoothUnion(
			sd.IsoscelesTriangle(gfx.V(16, 25+g.Y)),
			sd.OpTx(gfx.IM.Moved(gfx.V(0, 26)), func(sd gfx.SignedDistance) float64 {
				return sd.Rectangle(gfx.V(14, 10+g.X))
			}), 5,
		),
		sd.Rectangle(gfx.V(8, 30)),
	)
}

var w, h = 64, 64

func main() {
	n := 7

	g := &Game{
		N:     n,
		Image: gfx.NewPaletted(w, h, Palettes[n]),
	}

	ebiten.SetWindowSize(1024, 1024)
	ebiten.SetWindowDecorated(false)
	ebiten.RunGame(g)
}

// Palettes with 4 colors
// from https://i.redd.it/0svby0ssa7s41.png

var Palettes = gfx.Palettes{
	PaletteIce,
	PaletteBubblegum,
	PaletteDream,
	PaletteGreenApple,
	PalettePurpleBerry,
	PaletteDarkCherry,
	PaletteCardboard,
	PaletteOlive,
	PaletteSteel,
}

var PaletteIce = gfx.Palette{
	{0x9b, 0xeb, 0xeb, 0xff},
	{0x6d, 0xa1, 0xdf, 0xff},
	{0x66, 0x53, 0xcb, 0xff},
	{0x50, 0x1a, 0x68, 0xff},
}

var PaletteBubblegum = gfx.Palette{
	{0xf4, 0xe4, 0xd9, 0xff},
	{0xfd, 0x78, 0xad, 0xff},
	{0x05, 0x8e, 0xa8, 0xff},
	{0x2d, 0x2a, 0x01, 0xff},
}

var PaletteDream = gfx.Palette{
	{0xff, 0xec, 0x8d, 0xff},
	{0x34, 0xd9, 0xce, 0xff},
	{0xf4, 0x1c, 0x7d, 0xff},
	{0x3f, 0x0d, 0x68, 0xff},
}

var PaletteGreenApple = gfx.Palette{
	{0xf7, 0xff, 0xb7, 0xff},
	{0xa5, 0xd1, 0x45, 0xff},
	{0x2b, 0x80, 0x37, 0xff},
	{0x00, 0x1b, 0x27, 0xff},
}

var PalettePurpleBerry = gfx.Palette{
	{0xde, 0xfe, 0xff, 0xff},
	{0x97, 0xb6, 0xff, 0xff},
	{0xdc, 0x05, 0xef, 0xff},
	{0x01, 0x1f, 0x11, 0xff},
}

var PaletteDarkCherry = gfx.Palette{
	{0xff, 0xf5, 0xde, 0xff},
	{0xfd, 0x97, 0x85, 0xff},
	{0xf6, 0x08, 0x83, 0xff},
	{0x14, 0x02, 0x7a, 0xff},
}

var PaletteCardboard = gfx.Palette{
	{0xc5, 0xfb, 0xe1, 0xff},
	{0xc6, 0xaa, 0x35, 0xff},
	{0xaf, 0x53, 0x14, 0xff},
	{0x3c, 0x1e, 0x15, 0xff},
}

var PaletteOlive = gfx.Palette{
	{0xd4, 0xf1, 0xf0, 0xff},
	{0xa1, 0xb4, 0x67, 0xff},
	{0x7f, 0x6f, 0x00, 0xff},
	{0x2c, 0x25, 0x17, 0xff},
}

var PaletteSteel = gfx.Palette{
	{0xdc, 0xed, 0xeb, 0xff},
	{0x90, 0xad, 0xbb, 0xff},
	{0x56, 0x68, 0x9d, 0xff},
	{0x26, 0x23, 0x38, 0xff},
}

https://play.golang.org/p/NiFRO5pjLrh