save

camera.go

@@ -29,11 +29,18 @@ func (c *Camera)RealMatrix() Matrix {
 		return c.buf
 	}
 	g := Matrix{}
-	g.Translate(-c.Position.X, -c.Position.Y)
-	g.Rotate(c.Rotation)
-	siz := c.engine.AbsWinSize()
-	g.Translate(c.Around.X * siz.X, c.Around.Y * siz.Y)
-	g.Scale(c.Scale.X, c.Scale.Y)
+	position := c.Position().Neg()
+	around := c.Around()
+	scale  := c.Scale()
+	rotation := c.Rotation()
+
+	g.Translate(-position.X, -position.Y)
+	g.Rotate(rotation)
+
+	size := c.engine.AbsWinSize()
+	g.Translate(around.X * size.X, around.Y * size.Y)
+
+	g.Scale(scale.X, scale.Y)
 
 	c.buf = g
 	c.buffered = true

circle.go

@@ -11,14 +11,15 @@ type Circle struct {
 	Colority
 	Antialiasity
 	Layer
+	Radius Float
 }
 
 func (circle *Circle) Draw(c *Context) []EVertex {
-	rPos := circle.Position.Apply(c.Camera.RealMatrix())
+	rPos := circle.Position().Apply(c.Camera.RealMatrix())
 	vector.DrawFilledCircle(
 		c.Image,
 		float32(rPos.X), float32(rPos.Y),
-		float32(circle.Rotation),
+		float32(circle.Radius),
 		circle.Color,
 		circle.Antialias,
 	)

cmd/test/debug.go

@@ -13,6 +13,9 @@ type Debug struct {
 
 func (d *Debug) Draw(c *Context) []gg.EVertex {
 	e := c.Engine
+	relTri := tri.Rel()
+	relPlayer := player.Rel()
+	
 	keyStrs := []string{}
 	keyStrs = append(keyStrs, fmt.Sprintf(
 		"counter: %d", counter,
@@ -30,20 +33,20 @@ func (d *Debug) Draw(c *Context) []gg.EVertex {
 		"frame: %d", int(c.Frame()),
 	))
 	keyStrs = append(keyStrs, fmt.Sprintf(
-		"relPlayerPos: %v", player.Position,
+		"relPlayerPos: %v", relPlayer.Position(),
 	))
 	keyStrs = append(keyStrs, fmt.Sprintf(
-		"absPlayerPos: %v", player.AbsPosition(),
+		"absPlayerPos: %v", player.Position(),
 	))
 
 	keyStrs = append(keyStrs, fmt.Sprintf(
-		"relTriPos: %v", tri.Position,
+		"relTriPos: %v", tri.Position(),
 	))
 	keyStrs = append(keyStrs, fmt.Sprintf(
-		"absTriPos: %v", tri.AbsPosition(),
+		"absTriPos: %v", relTri.Position(),
 	))
 	keyStrs = append(keyStrs, fmt.Sprintf(
-		"absTriRot: %v", gg.Degree(tri.AbsRotation()),
+		"absTriRot: %v", gg.Degree(tri.Rotation()),
 	))
 
 	keys := []string{}
@@ -71,8 +74,8 @@ func (d *Debug) Draw(c *Context) []gg.EVertex {
 
 	keyStrs = append(keyStrs, fmt.Sprintf(
 		"camera position: %v %v",
-		c.Camera.Position.X,
-		c.Camera.Position.Y,
+		c.Camera.Position().X,
+		c.Camera.Position().Y,
 	))
 	keyStrs = append(keyStrs, fmt.Sprintf("realCursorPos: %v", e.CursorPosition()))
 	keyStrs = append(keyStrs, fmt.Sprintf("absCursorPos: %v", e.AbsCursorPosition()))

cmd/test/player.go

@@ -18,8 +18,8 @@ type Player struct {
 func NewPlayer() *Player {
 	ret := &Player{}
 	ret.Transform = gg.T()
-	ret.Scale = gg.V2(1)
-	ret.Around = gg.V2(.5)
+	ret.SetScale(gg.V2(1))
+	ret.SetAround(gg.V2(.5))
 	ret.MoveSpeed = 40.
 	ret.ScaleSpeed = .2
 	ret.Animations = playerAnimations
@@ -48,7 +48,7 @@ func (p *Player) Draw(c *Context) []gg.EVertex {
 }
 
 func (p *Player) Update(c *Context) {
-	p.Position.Y += 2
+	p.SetPosition(p.Position().Sub(gg.Y(2)))
 	if p.Spawned {
 		return
 	}
@@ -62,25 +62,30 @@ func (p *Player) Update(c *Context) {
 	for _, v := range keys {
 		switch v {
 		case gg.KeyQ:
-			p.Scale = p.Scale.Add(gg.V(p.ScaleSpeed*dt, 0))
+			p.SetScale(
+				p.Scale().Add(
+					gg.X(p.ScaleSpeed*dt),
+				),
+			)
 		case gg.KeyArrowUp:
-			cam.Position.Y += p.MoveSpeed * dt
-		case gg.KeyArrowLeft:
-			cam.Position.X -= p.MoveSpeed * dt
+			cam.Move(gg.Y(-p.MoveSpeed * dt))
 		case gg.KeyArrowDown:
-			cam.Position.Y -= p.MoveSpeed * dt
+			cam.Move(gg.Y(p.MoveSpeed * dt))
+		case gg.KeyArrowLeft:
+			cam.Move(gg.X(-p.MoveSpeed*dt))
 		case gg.KeyArrowRight:
-			cam.Position.X += p.MoveSpeed * dt
+			cam.Move(gg.X(p.MoveSpeed * dt))
 		case gg.KeyW:
-			p.Position.Y -= p.MoveSpeed * dt*10
+			p.Move(gg.Y(p.MoveSpeed * dt*10))
 			walking = true
 			p.Animate(Walk)
 		case gg.KeyA:
-			p.Position.X -= p.MoveSpeed * dt
-			p.Scale.X = -1
+			p.Move(gg.X(-MoveSpeed * dt))
+			p.SetScale(gg.V(-1, 1)
 			walking = true
 			p.Animate(Walk)
 		case gg.KeyS:
+			p.Move(gg.X(-MoveSpeed * dt))
 			p.Position.Y -= p.MoveSpeed * dt
 			walking = true
 			p.Animate(Walk)

engine.go

@@ -145,7 +145,7 @@ func (c *Engine) RealWinSize() Vector {
 }
 
 func (c *Engine) AbsWinSize() Vector {
-	return c.RealWinSize().Div(c.Camera.Scale)
+	return c.RealWinSize().Div(c.Camera.Scale())
 }
 
 func (e *Engine) EventInput() EventChan {

rect.go

@@ -19,7 +19,7 @@ type Rectangle struct {
 func (r Rectangle) Vertices() Vertices {
 	t := r.Transform
 	wh := V(r.Width, r.Height)
-	t.Around = t.Around.Scale(wh)
+	t.SetAround(t.Around().Mul(wh))
 	m := t.Matrix()
 	p1 := V(0, 0).Apply(m)
 	p2 := V(wh.X, 0).Apply(m)

sprite.go

@@ -55,8 +55,11 @@ func (s *Sprite) RectangleToDraw() Rectangle {
 	
 	w, h := s.Images[0].Size()
 	t := s.Transform
-	t.Around.X *= Float(w)
-	t.Around.Y *= Float(h)
+	t.SetAround(
+		t.Around().Mul(
+			V(Float(w), Float(h)),
+		),
+	)
 	
 	return Rectangle{
 		Transform: t,

transform.go

@@ -6,7 +6,7 @@ import (
 )
 
 type Transformer interface {
-	GetTransform() Transform
+	GetTransform() *Transform
 }
 
 // The structure represents basic transformation
@@ -14,18 +14,25 @@ type Transformer interface {
 type Transform struct {
 	// Absolute (if no parent) position and
 	// the scale.
-	Position, Scale Vector
+	position, scale Vector
 	// The object rotation in radians.
-	Rotation Float
+	rotation Float
 	// The not scaled offset vector from upper left corner
 	// which the object should be rotated around.
-	Around Vector
+	around Vector
+
 	// If is not nil then the upper values will be relational to
 	// the parent ones.
-	Parent Transformer
+	parent *Transform
+
+	// Dirty is true if we anyhow changed matrix.
+	dirty, parentDirty bool
+
+	matrix, parentMatrix, parentInverted Matrix
 }
 
-func (t Transform) GetTransform() Transform {
+// For implementing the Transformer on embedding.
+func (t *Transform) GetTransform() *Transform {
 	return t
 }
 
@@ -33,121 +40,190 @@ func (t Transform) GetTransform() Transform {
 func T() Transform {
 	ret := Transform{
 		// Rotate around
-		Scale: Vector{1, 1},
+		scale: Vector{1, 1},
 		// Rotate around the center.
-		Around: V(.5, .5),
+		around: V(.5, .5),
 	}
 	return ret
 }
 
-func (t *Transform) SetAbsPosition(absPosition Vector) {
-	if t.Parent == nil {
-		t.Position = absPosition
+// Set the absolute object position.
+func (t *Transform) SetPosition(position Vector) {
+	t.dirty = true
+	t.parentDirty = true
+	if t.parent == nil {
+		t.position = position
 		return
 	}
-	m := t.ParentMatrix()
-	m.Invert()
-	t.Position = absPosition.Apply(m)
+
+	_, mi := t.parent.MatrixForParenting()
+	t.position = position.Apply(mi)
+}
+
+// Set the absolute object rotation.
+func (t *Transform) SetRotation(rotation Float) {
+	t.dirty = true
+	t.parentDirty = true
+	if t.parent == nil {
+		t.rotation = rotation
+		return
+	}
+	t.rotation -= t.parent.Rotation()
+}
+
+// Set the absolute object scale.
+func (t *Transform) SetScale(scale Vector) {
+	t.dirty = true
+	t.scale = scale
+}
+
+func (t *Transform) SetAround(around Vector) {
+	t.dirty = true
+	t.around = around
 }
 
 // Get the absolute representation of the transform.
-func (t Transform) Abs() Transform {
-	if t.Parent == nil {
-		return t
+func (t *Transform) Abs() Transform {
+	if t.parent == nil {
+		return *t
 	}
 
 	ret := T()
-	ret.Position = t.AbsPosition()
-	ret.Rotation = t.AbsRotation()
-	ret.Scale = t.AbsScale()
+	ret.position = t.Position()
+	ret.rotation = t.Rotation()
+
+	// Do not need that
+	// cause parent does not affect
+	// scaling.
+	// (Should think if scaling from parent
+	// can be used anyhow)
+
+	//ret.scale = t.Scale()
 
 	return ret
 }
 
-func (t Transform) AbsPosition() Vector {
-	if t.Parent == nil {
-		return t.Position
-	}
-	return t.Position.Apply(t.ParentMatrix())
+func (t *Transform) Rel() Transform {
+	ret := *t
+	ret.parent = nil
+	return ret
 }
 
-func (t Transform) AbsScale() Vector {
-	if t.Parent == nil {
-		return t.Scale
+// Get the absolute object position.
+func (t *Transform) Position() Vector {
+	if t.parent == nil {
+		return t.position
 	}
-	return V2(1)
+	pm, _ := t.parent.MatrixForParenting()
+	return t.position.Apply(pm)
 }
 
-func (t Transform) AbsRotation() Float {
-	if t.Parent == nil {
-		return t.Rotation
-	}
-	return t.Rotation + t.Parent.GetTransform().AbsRotation()
+func (t *Transform) Move(v ...Vector) {
+	t.SetPosition(t.Position().Add(v...))
 }
 
-func (t *Transform) SetAbsRotation(rot Float) {
-	if t.Parent == nil {
-		t.Rotation = rot
-	}
-	t.Rotation -= t.Parent.GetTransform().AbsRotation()
+// Get the absolute object scale.
+func (t *Transform) Scale() Vector {
+	return t.scale
 }
 
+// Get the absolute object rotation.
+func (t *Transform) Rotation() Float {
+	if t.parent == nil {
+		return t.rotation
+	}
+	return t.rotation + t.parent.Rotation()
+}
+func (t *Transform) Around() Vector {
+	return t.around
+}
+
+// Returns true if the object is connected
+// to some parent.
 func (t *Transform) Connected() bool {
-	return t.Parent != nil
+	return t.parent != nil
 }
 
+// Connect the object to another one making
+// it its parent.
 func (t *Transform) Connect(parent Transformer) {
-	absPosition := t.AbsPosition()
-	absRotation := t.AbsRotation()
-	t.Parent = parent
-	t.SetAbsPosition(absPosition)
-	t.SetAbsRotation(absRotation)
+	absPosition := t.Position()
+	absRotation := t.Rotation()
+	t.parent = parent.GetTransform()
+	t.SetPosition(absPosition)
+	t.SetRotation(absRotation)
 }
 
+// Disconnect from the parent.
 func (t *Transform) Disconnect() {
-	if t.Parent == nil {
+	if t.parent == nil {
 		return
 	}
 	*t = t.Abs()
 }
 
-func (t Transform) ParentMatrix() Matrix {
-	g := Matrix{}
-	if t.Parent == nil {
-		return g
+// Return the matrix and the inverted one for parenting children.
+func (t *Transform) MatrixForParenting() (Matrix, Matrix) {
+	var m, mi Matrix
+
+	if t.parentDirty {
+
+		m.Scale(t.scale.X, t.scale.Y)
+		m.Rotate(t.rotation)
+		m.Translate(t.position.X, t.position.Y)
+		t.parentMatrix = m
+
+		mi := m
+		mi.Invert()
+		t.parentInverted = mi
+
+		t.parentDirty = false
+	} else {
+		m = t.parentMatrix
+		mi = t.parentInverted
 	}
 
-	p := t.Parent.GetTransform()
-	g = p.ParentMatrix()
+	if t.parent != nil {
+		pm, pmi := t.parent.MatrixForParenting()
+		m.Concat(pm)
+		mi.Concat(pmi)
+	}
+
+	return m, mi
 
-	g.Scale(p.Scale.X, p.Scale.Y)
-	g.Rotate(p.Rotation)
-	g.Translate(p.Position.X, p.Position.Y)
 
-	return g
 }
 
 // Returns the GeoM with corresponding
 // to the transfrom transformation.
-func (t Transform)Matrix() Matrix {
-	g := Matrix{}
+func (t *Transform)Matrix() Matrix {
+	var m, pm Matrix
 
+	// Calculating only if we changed the structure anyhow.
+	if t.dirty {
 		// Scale first.
-	g.Scale(t.Scale.X, t.Scale.Y)
-
+		m.Scale(t.scale.X, t.scale.Y)
 		// Then move and rotate.
-	g.Translate(
-		-t.Around.X * t.Scale.X,
-		-t.Around.Y * t.Scale.Y,
+		m.Translate(
+			-t.around.X * t.scale.X,
+			-t.around.Y * t.scale.Y,
 		)
-	g.Rotate(t.Rotation)
-
+		m.Rotate(t.rotation)
 		// And finally move to the absolute position.
-	g.Translate(t.Position.X, t.Position.Y)
+		m.Translate(t.position.X, t.position.Y)
+		t.matrix = m
 
-	m := t.ParentMatrix()
-	g.Concat(m)
+		// Setting the flag so we d
+		t.dirty = false
+	} else {
+		m = t.matrix
+	}
 
-	return g
+	if t.parent != nil {
+		pm, _ = t.parent.MatrixForParenting()
+		m.Concat(pm)
+	}
+
+	return m
 }
 

vector.go

@@ -22,7 +22,15 @@ func V(x, y Float) Vector {
 }
 
 func V2(v Float) Vector {
-	return V(v, v)
+	return Vector{v, v}
+}
+
+func X(x Float) Vector {
+	return Vector{x, 0}
+}
+
+func Y(y Float) Vector {
+	return Vector{0, y}
 }
 
 func (v Vector) Div(o Vector) Vector {
@@ -32,7 +40,7 @@ func (v Vector) Div(o Vector) Vector {
 	)
 }
 
-func (v Vector) Scale(o Vector) Vector {
+func (v Vector) Mul(o Vector) Vector {
 	return V(
 		v.X * o.X,
 		v.Y * o.Y,
@@ -78,7 +86,7 @@ func (v Vector) Neg() Vector {
 }
 
 // Returns the vector rotated by "a" angle in radians.
-func (v Vector) Rotate(a Float) Vector {
+func (v Vector) Rot(a Float) Vector {
 	m := Matrix{}
 	m.Rotate(a)
 	return v.Apply(m)