First commit >:]

reward.go

@@ -0,0 +1,104 @@
+package main
+
+import (
+	"bytes"
+	_ "embed"
+	"image"
+	_ "image/png"
+	"log"
+
+	"github.com/hajimehoshi/ebiten/v2"
+)
+
+const (
+	REWARD_HEIGHT = 32
+	REWARD_WIDTH  = 32
+
+	SHINY_ANIMATION_CYCLES = 9
+	SHINY_ROW_INDEX        = 11
+	SPARKLE_ROW_INDEX      = 7
+)
+
+var (
+	//go:embed resources/images/gold.png
+	assetsReward_png []byte
+	rewardsImage     *ebiten.Image
+
+	//go:embed resources/images/shiny.png
+	assetsShiny_png []byte
+	shinyImage      *ebiten.Image
+)
+
+type Reward struct {
+	Sprite  *ebiten.Image
+	scratch *ebiten.Image
+	cycle   int
+}
+
+func NewReward() *Reward {
+	r := &Reward{
+		cycle: 0,
+	}
+	r.Sprite = ebiten.NewImageFromImage(rewardsImage)
+	r.scratch = ebiten.NewImageFromImage(rewardsImage)
+	return r
+}
+
+func (r *Reward) Animate() {
+
+	r.scratch.Clear()
+	r.Sprite.Clear()
+
+	r.scratch.DrawImage(rewardsImage.SubImage(image.Rect(0, 0, REWARD_WIDTH, REWARD_HEIGHT)).(*ebiten.Image), nil)
+
+	if r.cycle < SHINY_ANIMATION_CYCLES {
+		//add sheen
+		op := &ebiten.DrawImageOptions{}
+		op.Blend = ebiten.BlendSourceAtop
+
+		sx := r.cycle * REWARD_WIDTH
+		sy := REWARD_HEIGHT * SHINY_ROW_INDEX
+
+		ex := sx + REWARD_WIDTH
+		ey := sy + REWARD_HEIGHT
+
+		r.scratch.DrawImage(shinyImage.SubImage(image.Rect(sx, sy, ex, ey)).(*ebiten.Image), op)
+
+		//add sparkle
+		spsy := REWARD_HEIGHT * SPARKLE_ROW_INDEX
+		spey := spsy + REWARD_HEIGHT
+		op.GeoM.Translate(REWARD_WIDTH/2, REWARD_HEIGHT/2)
+		r.scratch.DrawImage(shinyImage.SubImage(image.Rect(sx, spsy, ex, spey)).(*ebiten.Image), nil)
+	}
+
+	r.Sprite.DrawImage(r.scratch, nil)
+	r.CycleUpdate()
+}
+
+func (r *Reward) CycleUpdate() {
+	r.cycle = (r.cycle + 1) % (SHINY_ANIMATION_CYCLES * 8)
+}
+
+func (r *Reward) Width() int {
+	return REWARD_WIDTH
+}
+
+func (r *Reward) Height() int {
+	return REWARD_HEIGHT
+}
+
+func init() {
+
+	img, _, err := image.Decode(bytes.NewReader(assetsReward_png))
+	if err != nil {
+		log.Fatal(err)
+	}
+	rewardsImage = ebiten.NewImageFromImage(img)
+
+	img, _, err = image.Decode(bytes.NewReader(assetsShiny_png))
+	if err != nil {
+		log.Fatal(err)
+	}
+	shinyImage = ebiten.NewImageFromImage(img)
+
+}