Fade Colors on a Polygon using the Game Loop
One of the features I need to implement is to smoothly change the fill/stroke color of a polygon, like this: A manual approach In order to better understand the mechanics, I built my own fading PoC. First, one would need to build the polygon:
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hud = display.newGroup() -- Build the text layer score = display.newText{ text = "Level: " .. name .. " - (" .. "11".. " groups)", font = "scene/game/font/Mecha.ttf", fontSize = "32" } snap(score, "topcenter", 8) -- Build the background hudBG = display.newRoundedRect(score.x, score.y, score.width+64, score.height+32, 8) hudBG.fill = {0,0,0} -- Build the view hud:insert(scene.hudBG) hud:insert(scene.score) view:insert(hud) |
In this particular case, I have a text field and a rounded rectangle beneath it. the hud group contains both in the right order. Once the components have been created, we build the function to be called each frame:
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hudBG.iterator = 100 hudBG.lastTime = getTimer() hudBG.enterFrame = function(self) local curTime = getTimer() local dt = curTime-self.lastTime dt = dt / 1000 self.lastTime = curTime if(self.iterator > 0) then -- print(1.0/dt) self.iterator = self.iterator - 1 self.fill={1-self.iterator/100.0, 0,0} end end |
The idea is to only…read more