Improved player movement on ropes

main.go

@@ -5,26 +5,18 @@ import (
 	"math/rand"
 )
 
-var smiley = [8]byte{
-	0b11000011,
-	0b10000001,
-	0b00100100,
-	0b00100100,
-	0b00000000,
-	0b00100100,
-	0b10011001,
-	0b11000011,
-}
-
 var gravity = 0.2
 var points []*Point = []*Point{}
 var sticks []*Stick = []*Stick{}
 var player *Player
 var frame uint64 = 0
 var lightIndex uint64 = 0
+var camX = 0
+var camY = 0
 
 //go:export start
 func start() {
+
 	rand.Seed(654654321348654)
 	points = []*Point{}
 	sticks = []*Stick{}
@@ -34,13 +26,23 @@ func start() {
 	w4.PALETTE[3] = 0xff4d6d
 	for i := 0; i < 4; i++ {
 		p, s := CreateRope(
-			Vector{0, rand.Float64()*40 + float64(i*40)},
 			Vector{160, rand.Float64()*40 + float64(i*40)},
+			Vector{0, rand.Float64()*40 + float64(i*40)},
 			10,
 		)
 		points = append(points, p...)
 		sticks = append(sticks, s...)
 	}
+	for i := 0; i < 3; i++ {
+		p, s := CreateRope(
+			Vector{float64(i*30 + 30), 0},
+			Vector{float64(i*30 + 40), 100},
+			10,
+		)
+		p[len(p)-1].IsLocked = false
+		points = append(points, p...)
+		sticks = append(sticks, s...)
+	}
 	player = &Player{
 		Position:     Vector{80, 80},
 		Speed:        Vector{},

player.go

@@ -3,6 +3,7 @@ package main
 import (
 	"cart/w4"
 	"math"
+	"strconv"
 )
 
 type Player struct {
@@ -13,30 +14,34 @@ type Player struct {
 	StickOffset  float64
 	GrabTimeout  uint
 	Gamepad      *uint8
+	GamepadLast  uint8
 }
 
 func (p *Player) Update() {
-	p.Speed.X = 0
+	lastGamepad := *p.Gamepad & (*p.Gamepad ^ p.GamepadLast)
+	p.GamepadLast = *p.Gamepad
 	if p.GrabTimeout > 0 {
 		p.GrabTimeout--
 	}
-	if *p.Gamepad&w4.BUTTON_LEFT != 0 {
-		p.Speed.X -= 1
-	}
-	if *p.Gamepad&w4.BUTTON_RIGHT != 0 {
-		p.Speed.X += 1
-	}
 	isJumping := *p.Gamepad&w4.BUTTON_DOWN == 0
 	p.Speed.Y = math.Min(4, p.Speed.Y+gravity)
 	if p.StickGrabbed != nil {
 		p.Speed.Y = 0
+		p.Speed.X = 0
 		//		p.Position = p.PointGrabbed.Position
 		if *p.Gamepad&w4.BUTTON_LEFT != 0 {
-			p.StickOffset -= 0.1
+			p.Speed.X -= 1
 		}
 		if *p.Gamepad&w4.BUTTON_RIGHT != 0 {
-			p.StickOffset += 0.1
+			p.Speed.X += 1
 		}
+		if *p.Gamepad&w4.BUTTON_UP != 0 {
+			p.Speed.Y -= 1
+		}
+		if *p.Gamepad&w4.BUTTON_DOWN != 0 {
+			p.Speed.Y += 1
+		}
+		p.MoveOnRope(p.Speed)
 		if p.StickOffset < 0 {
 			point := p.StickGrabbed.PointA
 			if len(point.Sticks) == 1 {
@@ -56,11 +61,14 @@ func (p *Player) Update() {
 			}
 		}
 		p.Position = p.StickGrabbed.GetPosition(p.StickOffset)
-		if *p.Gamepad&w4.BUTTON_2 != 0 {
+		if lastGamepad&w4.BUTTON_2 != 0 {
 			p.GrabTimeout = 10
 			if isJumping {
-				p.GrabTimeout = 5
+				p.GrabTimeout = 10
-				p.Speed.Y = -4.5
+				p.Speed = p.Speed.MulScalar(2)
+				if p.Speed.Y <= 0 {
+					p.Speed.Y -= 1 * 2
+				}
 				impulse := p.Speed.MulScalar(-1)
 				p.StickGrabbed.PointA.Position.MoveVec(impulse)
 				p.StickGrabbed.PointB.Position.MoveVec(impulse)
@@ -90,6 +98,7 @@ func (p *Player) Update() {
 				}
 			}
 			if stickDistance < 4 {
+				w4.Trace(strconv.FormatFloat(stickDistance, 'f', 3, 64))
 				p.StickGrabbed = selectedStick
 				p.StickOffset = selectedStick.GetOffset(p.Position)
 				p.StickGrabbed.PointA.Position.MoveVec(p.Speed)
@@ -99,6 +108,12 @@ func (p *Player) Update() {
 	}
 }
 
+func (p *Player) MoveOnRope(motion Vector) {
+	newPos := p.Position.Sum(motion)
+	offset := p.StickGrabbed.GetOffset(newPos)
+	p.StickOffset = offset
+}
+
 func (p *Player) Draw() {
 	*w4.DRAW_COLORS = 0x34
 	w4.Rect(int(p.Position.X)-4, int(p.Position.Y)-4, 8, 8)

ropes.go

@@ -58,7 +58,7 @@ func (s *Stick) GetDistance(point Vector) float64 {
 		return ap.Len()
 	}
 	mod := ab.Len()
-	return math.Abs(ab.X*ap.Y-ab.Y*ab.X) / mod
+	return math.Abs(ab.X*ap.Y-ab.Y*ap.X) / mod
 }
 
 func (s *Stick) GetPosition(offset float64) Vector {
@@ -70,7 +70,12 @@ func (s *Stick) GetOffset(p Vector) float64 {
 	ab := s.GetVector()
 	ap := p.Sub(s.PointA.Position)
 	projection := ap.ProjectTo(ab)
-	return projection.Len() / ab.Len()
+	dot := ab.Dot(ap)
+	result := projection.Len() / ab.Len()
+	if dot < 0 {
+		result *= -1
+	}
+	return result
 }
 
 func (s *Stick) Draw() {