Add walking animation

component/player.go

@@ -99,9 +99,14 @@ type Player struct {
 	Color     color.Color
 	PlayerNum int
 
+	Grounded bool
+
 	Action          PlayerAction
 	ActionTicksLeft int
 
+	WalkFrame        int
+	WalkFrameReverse bool
+
 	NoPunch bool
 	NoKick  bool
 
@@ -118,8 +123,25 @@ func (p *Player) Clone() Player {
 	return result
 }
 
+func (p *Player) Walking() bool {
+	const walkThreshold = 0.2
+	return p.Grounded && p.Action == ActionIdle && (p.VX < -walkThreshold || p.VX > walkThreshold)
+}
+
 func TranslateRect(r image.Rectangle, x int, y int) image.Rectangle {
 	r.Min.X, r.Min.Y = r.Min.X+x, r.Min.Y+y
 	r.Max.X, r.Max.Y = r.Max.X+x, r.Max.Y+y
 	return r
 }
+
+// WalkFrames are defined in chronological order.
+var WalkFrames = []*ebiten.Image{
+	asset.FrameAt(asset.ImgPlayer, 0, 13),
+	asset.FrameAt(asset.ImgPlayer, 1, 13),
+	asset.FrameAt(asset.ImgPlayer, 2, 13),
+	asset.FrameAt(asset.ImgPlayer, 3, 13),
+	asset.FrameAt(asset.ImgPlayer, 4, 13),
+	asset.FrameAt(asset.ImgPlayer, 5, 13),
+	asset.FrameAt(asset.ImgPlayer, 6, 13),
+	asset.FrameAt(asset.ImgPlayer, 7, 13),
+}

game/game.go

@@ -68,6 +68,7 @@ func (g *Game) reset() {
 		ActionTicksLeft: len(component.AllPlayerFrames[component.ActionIdle]),
 		X:               -playerSpawnGap - component.PlayerWidth,
 		Y:               0,
+		Grounded:        true,
 	}
 
 	g.Players[1] = component.Player{
@@ -77,6 +78,7 @@ func (g *Game) reset() {
 		ActionTicksLeft: len(component.AllPlayerFrames[component.ActionIdle]),
 		X:               playerSpawnGap,
 		Y:               0,
+		Grounded:        true,
 	}
 
 	g.Winner = 0
@@ -266,7 +268,6 @@ func (g *Game) applyPhysics() {
 		}
 
 		outOfBounds := p.Y < -world.GroundHeight-component.PlayerHeight
-
 		if outOfBounds {
 			p.VX, p.VY = 0, 0
 		} else if collideG == -1 && p.VY > -world.Gravity {
@@ -288,6 +289,26 @@ func (g *Game) applyPhysics() {
 			p.VX, p.VY = 0, 0
 		}
 
+		p.Grounded = collideG != -1
+
+		// Advance walking animation frame.
+		if p.Walking() {
+			const walkFrames = 8
+			if p.WalkFrameReverse {
+				p.WalkFrame--
+				if p.WalkFrame < 0 {
+					p.WalkFrame = 1
+					p.WalkFrameReverse = false
+				}
+			} else {
+				p.WalkFrame++
+				if p.WalkFrame >= walkFrames {
+					p.WalkFrame = walkFrames - 2
+					p.WalkFrameReverse = true
+				}
+			}
+		}
+
 		if collideX != -1 && collideY != -1 {
 			collideRect := world.PhysicsRects[collideX]
 
@@ -408,17 +429,8 @@ func (g *Game) UpdateByInputs(inputs []InputBits) {
 				continue
 			}
 
-			if input.isButtonOn(ButtonUp) && !component.TranslateRect(playerRect, 0, -1).Overlaps(oppRect) {
-				var grounded bool
-				for _, physRect := range world.PhysicsRects {
-					if g.Players[i].Y < float64(physRect.Max.Y)+world.FloatValueThreshold && g.Players[i].Y > float64(physRect.Max.Y)-world.FloatValueThreshold {
-						grounded = true
-						break
-					}
-				}
-				if grounded {
-					g.Players[i].VY = world.JumpVelocity
-				}
+			if input.isButtonOn(ButtonUp) && g.Players[i].Grounded {
+				g.Players[i].VY = world.JumpVelocity
 			}
 			if input.isButtonOn(ButtonDown) && !component.TranslateRect(playerRect, 0, 1).Overlaps(oppRect) {
 				//g.Players[i].VY = -1

system/map.go

@@ -38,20 +38,18 @@ func (s *MapSystem) Draw(e gohan.Entity, screen *ebiten.Image) error {
 
 	screen.Fill(color.RGBA{0, 100, 100, 255})
 
-	groundColor := color.RGBA{50, 50, 50, 255}
-
-	const groundTopHeight = 10
-	//groundTopColor := color.RGBA{100, 100, 100, 255}
+	const groundBorderSize = 3
+	groundBorderColor := color.RGBA{30, 30, 30, 255}
+	groundColor := color.RGBA{20, 20, 20, 255}
 
 	for _, r := range world.PhysicsRects {
-		screen.SubImage(world.GameRectToScreen(r)).(*ebiten.Image).Fill(groundColor)
+		groundRect := world.GameRectToScreen(r)
+		screen.SubImage(groundRect).(*ebiten.Image).Fill(groundBorderColor)
+
+		inset := groundRect.Inset(groundBorderSize)
+		inset.Max.Y += groundBorderSize
+		screen.SubImage(inset).(*ebiten.Image).Fill(groundColor)
 	}
 
-	/*r := image.Rect(-world.GroundWidth/2, -world.ScreenHeight, world.GroundWidth/2, 0)
-	screen.SubImage(world.GameRectToScreen(r)).(*ebiten.Image).Fill(groundColor)
-
-	r = image.Rect(-world.GroundWidth/2, -groundTopHeight, world.GroundWidth/2, 0)
-	screen.SubImage(world.GameRectToScreen(r)).(*ebiten.Image).Fill(groundTopColor)*/
-
 	return nil
 }

system/player.go

@@ -58,6 +58,10 @@ func (s *PlayerSystem) Draw(e gohan.Entity, screen *ebiten.Image) error {
 			break
 		}
 
+		if p.Walking() {
+			sprite = component.WalkFrames[p.WalkFrame]
+		}
+
 		if sprite != nil {
 			x, y := world.GameCoordsToScreen(p.X-24, p.Y+64)
 			op := &ebiten.DrawImageOptions{}

system/ui.go

@@ -266,11 +266,11 @@ func (u *UISystem) Draw(e gohan.Entity, screen *ebiten.Image) error {
 		label := fmt.Sprintf("OPPONENT TYPE: %s (CONTROL+O)", aiLabel)
 		ebitenutil.DebugPrint(u.tmpImg, label)
 
-		width := float64(len(label) * 6)
+		width := float64(len(label) * 12)
 
 		op := &ebiten.DrawImageOptions{}
 		op.GeoM.Reset()
-		op.GeoM.Scale(1, 1)
+		op.GeoM.Scale(2, 2)
 		op.GeoM.Translate(world.InternalScreenWidth/2-width/2, 0)
 		screen.DrawImage(u.tmpImg, op)
 	}