Rotating around a fixed point

aditya

Need to move a sprite around a fixed point. The caveat is, the motion should start from the 'current position' of the sprite.
Offsetting the angle i.e.using magic numbers, doesn't really do it since it will be different in case the distance between the sprite and the fixed point is changed.

local block1Texture = Texture.new("block1.png",true) local block1 = Bitmap.new(block1Texture) block1:setAnchorPoint(0.5,0.5) stage:addChild(block1) block1:setPosition(50,50)   local block2Texture = Texture.new("block2.png",true) local block2 = Bitmap.new(block2Texture) block2:setAnchorPoint(0.5,0.5) stage:addChild(block2) block2:setPosition(350,450)   local block3Texture = Texture.new("block3.png",true) local block3 = Bitmap.new(block3Texture) block3:setAnchorPoint(0.5,0.5) stage:addChild(block3) block3:setPosition(300,700)   local timer = Timer.new(500, 1)   local rotateAroundBlock = block2   function getCharAngleFromRope(startX, startY, targetX, targetY) local xdiff = targetX - startX local ydiff = targetY - startY local ang = math.atan2( ydiff, xdiff ) ang = math.deg(ang) + 90.0 if ang < 0 then ang = 360.0 + ang end return ang end   local dx = application:getLogicalTranslateX() / application:getLogicalScaleX() local dy = application:getLogicalTranslateY() / application:getLogicalScaleY()   local function onTimerComplete(event) timer:reset() timer:start()   if(rotateAroundBlock==block1) then angle = angle - 0.1 else angle = angle + 0.1 end   local px = rotateAroundBlock:getX() + dist*math.cos(angle) local py = rotateAroundBlock:getY() + dist*math.sin(angle)   if(px<=0 or px>=application:getDeviceWidth()) then --print("1") --px = block3:getX() end   if(py<=0 or py>=application:getContentHeight()) then --print("2") --py = block3:getY() --px = block3:getX() end   block3:setPosition(px,py) end dist = math.sqrt((rotateAroundBlock:getX()-block3:getX())^2+(rotateAroundBlock:getY()-block3:getY())^2) angle = getCharAngleFromRope(block3:getX(),block3:getY(),rotateAroundBlock:getX(),rotateAroundBlock:getY()) timer:addEventListener(Event.TIMER_COMPLETE, onTimerComplete)   function startMoving() timer:start() end stage:addEventListener(Event.TOUCHES_BEGIN, startMoving)

[Edit: Solved. math.cos and math.sin take parameters as radians and not degrees]