Holes in image using setBlendMode and renderTarget

Comments

• HubertRonald Member

  June 2014

  Hi @paulfen
  
  I know that is not the solution you are looking for but I think this is a good start

  -- class shape unHide = Core.class(Sprite)   -- texture or region than you want to show function unHide:init() self.shape = Shape.new() self.shape:setX(50) self.shape:setY(50) self:draw()   self.isFocus = false   self:addEventListener(Event.MOUSE_DOWN, self.onMouseDown, self) self:addEventListener(Event.MOUSE_MOVE, self.onMouseMove, self) self:addEventListener(Event.MOUSE_UP, self.onMouseUp, self)   self:addChild(self.shape) end   --show box function unHide:draw() self:setVisible(true) local fc = 2 -- it's because move the mouse is fast maybe you must be global to local position self.texture = Texture.new("black-cat.jpg",true) self.matrix = Matrix.new(1, 0, 0, 1, 48, 50) self.shape:setLineStyle(3, 0x000000) self.shape:setFillStyle(Shape.TEXTURE, self.texture, self.matrix) self.shape:beginPath() self.shape:moveTo(self.shape:getX()*fc-100, self.shape:getY()*fc-100) self.shape:lineTo(self.shape:getX()*fc+100, self.shape:getY()*fc-100) self.shape:lineTo(self.shape:getX()*fc+100, self.shape:getY()*fc+100) self.shape:lineTo(self.shape:getX()*fc-100, self.shape:getY()*fc+100) self.shape:closePath() self.shape:endPath() end   -- hide box function unHide:hide() self.shape:clear() self:setVisible(false) end   -- press left button over box function unHide:onMouseDown(event) if self:hitTestPoint(event.x, event.y) then   self.isFocus = true   self.x0 = event.x self.y0 = event.y   event:stopPropagation() end end   -- move box function unHide:onMouseMove(event) if self.isFocus then   local dx = event.x - self.x0 local dy = event.y - self.y0   self.shape:setX(self.shape:getX() + dx) self.shape:setY(self.shape:getY() + dy)   self.x0 = event.x self.y0 = event.y   self:hide(); self:draw() event:stopPropagation() end end   -- up left button function unHide:onMouseUp(event) if self.isFocus then self.isFocus = false event:stopPropagation() end end   -- up canvas local bg = Bitmap.new(Texture.new("smiley-face-fun.jpg",true)) bg:setAnchorPoint(0.5,0.5) bg:setPosition(160,bg:getHeight()*.5) stage:addChild(bg)   -- create class square = unHide.new() stage:addChild(square)

  here also attached graphics that I used
  
  
  

  

  

  black-cat.jpg

  360 x 480 - 23K

  

  

  smiley-face-fun.jpg

  360 x 480 - 10K

  Likes: ar2rsawseen

  black-cat.jpg 23.5K

  smiley-face-fun.jpg 10.1K

  
  [-] Liasoft

  +1 -1 (+1 / -0 )Share on Facebook
• paulfen Member

  June 2014

  Thanks for the comment HubertRonald. As you suggested it did not solve my problem directly, but it did provide inspiration for me to find the solution!
  
  My solution involves drawing a circle (using the Arc class) over my large image, setting the circles fillStyle to solid and 0 alpha - i.e transparent. Then setting its blend mode to "noAlpha". Seems to do the trick and I can add as many circles as needed to punch more holes in my large image.

  local renderTarget = RenderTarget.new(W, H) local img = Bitmap.new(TextureRegion.new(renderTarget,0,0,W,H)) displayGroup:addChild(img) renderTarget:clear(0x000000, 0)   local clouds = Bitmap.new(pack:getTextureRegion("clouds.png")) clouds:setAnchorPoint(0.5, 0.5) clouds:setScale(8) renderTarget:draw(clouds)   local circle = Arc.new{x=100, y=100, radius=20, fillStyle={ Shape.SOLID, 0x000000, 0 }, lineStyle={ 0, 0xffffff, 0.0 }} circle:setBlendMode("noAlpha") circle:setScale(0.5) renderTarget:draw(circle)

  +1 -1Share on Facebook
• HubertRonald Member

  June 2014

  I'm glad for you @paulfen

  
  [-] Liasoft

  +1 -1Share on Facebook