How to rotate a triangle around the circle correct? - ios

Question

i have triangle around the circle and i created that If my character collides with a brick, then the triangles on the circle replacing another location on the circle.
but i have problem , the triangles rotating when its happening.
This happens when I click the screen (and thats fine) but its rotating.
it need looks like that :
but its look like that :
AddTriangleToCircle func :
func AddTriangleToCircle(Circle: SKShapeNode, Location: CGFloat, Inside: Bool) {
Triangle = SKSpriteNode(imageNamed: "Triangle.png")
Triangle.size = CGSize(width: 30, height: 30)
Triangle.anchorPoint.y = 0
let path = CGPathCreateMutable()
CGPathMoveToPoint(path, nil,298,2)
CGPathAddLineToPoint(path, nil,149,298)
CGPathAddLineToPoint(path, nil,0,0)
CGPathAddLineToPoint(path, nil,298,2)
CGPathCloseSubpath(path)
Triangle.physicsBody = SKPhysicsBody(polygonFromPath: path)
if Inside == true {
// Inside Triangle
Triangle.zRotation = CGFloat(M_PI_2)
} else {
// Outside Triangle
Triangle.zRotation = CGFloat(-M_PI_2)
}
Triangle.position = CGPoint(x:0.5, y:circleRadius)
let rotationSpeed1 = rotationSpeed + Location;
var angleRelatedToCircle1 = angleRelatedToCircle;
angleRelatedToCircle1 -= rotationSpeed1
Triangle.zRotation -= rotationSpeed1
Triangle.position.x = circleRadius * cos(angleRelatedToCircle1)
Triangle.position.y = circleRadius * sin(angleRelatedToCircle1)
//Triangle.physicsBody = SKPhysicsBody(texture:TriangelSKT, size: CGSize(width: 30, height:30))
let centerPoint = CGPointMake(Triangle.size.width / 2 - (Triangle.size.width * Triangle.anchorPoint.x), Triangle.size.height / 2 - (Triangle.size.height * Triangle.anchorPoint.y))
Triangle.physicsBody = SKPhysicsBody(rectangleOfSize: Triangle.size , center: centerPoint)
Triangle.physicsBody?.categoryBitMask = triangleCategory
Triangle.physicsBody?.contactTestBitMask = heroCategory
Triangle.physicsBody?.collisionBitMask = heroCategory
Triangle.physicsBody?.allowsRotation = false
// Set Dynamic to false
Triangle.physicsBody?.dynamic = false
Circle.addChild(Triangle);
}
AddCircle func :
func AddCircle() {
Circle = SKShapeNode(circleOfRadius: circleRadius)
Circle.position = CGPoint(x: self.size.width/2, y: self.size.height/2)
Circle.strokeColor = UIColor.whiteColor()
Circle.lineWidth = 9.5
Circle.fillColor = UIColor(red:0.98, green:0.82, blue:0.32, alpha:1.0)
self.addChild(Circle)
Circle.addChild(BooCharacter)
self.AddTriangleToCircle(Circle, Location: CGFloat(random(1...100)), Inside: false)
self.AddBrickToCircle(Circle, Location: CGFloat(random(1...200)), inside: true)
self.AddTriangleToCircle(Circle, Location: CGFloat(random(1...400)), Inside: false)
}
touchsbegan func :
override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
BooCharacter.zRotation += CGFloat(M_PI)
TapToStart.removeFromParent()
for touch in touches {
let location = touch.locationInNode(self)
}
initializeValues()
}
initializeValues func :
func initializeValues() {
self.removeAllChildren()
AddCircle()
}

Answer 1

So what you need is to find two points on a circle based on an angle.
A point on a circle is found this way -
func pointOnCircle(radius:CGFloat, angleInRadians:CGFloat, circleCenter:CGPoint) -> CGPoint {
return CGPoint(
x:circleCenter.x - radius * cos(angleInRadians),
y:circleCenter.y - radius * sin(angleInRadians)
)
}
Don't forget to convert from degrees to radians if needed.
You need to define an angle (which defines the triangle's size) and a starting point on the circle.
Use that angle to find the other base point of the triangle on the circle with the formula, and use it again only with a smaller angle (half of the original angle probably would do fine) and a larger radius, since the third point of the triangle can be thought of as if it is located on a larger circle (the red border circle), which shares the same center point as your original circle (the green one)