Add Glass Floor example

Author: dacap

Glass Floor.lua

@@ -0,0 +1,43 @@
+----------------------------------------------------------------------
+-- Creates a new layer that looks like a glass floor flattening the
+-- selected layers in the timeline.
+----------------------------------------------------------------------
+
+do
+  local spr = app.activeSprite
+  if not spr then return app.alert "There is no active sprite" end
+
+  app.transaction(
+    function()
+      local bounds = Rectangle()
+      local layers = app.range.layers
+      local newLayer = spr:newLayer()
+      newLayer.name = "Glass Floor"
+      newLayer.opacity = 128
+
+      for _,frame in ipairs(spr.frames) do
+        for _,layer in ipairs(layers) do
+          local img = Image(spr.spec)
+          for _,l in ipairs(layers) do
+            local layerCel = l:cel(frame)
+            if layerCel then
+              img:drawImage(layerCel.image, layerCel.position)
+              bounds = bounds:union(layerCel.bounds)
+            end
+          end
+
+          spr:newCel(newLayer, frame, img, Point(0, 0))
+        end
+      end
+
+      local oldFrame = app.activeFrame
+      app.activeLayer = newLayer
+      for _,cel in ipairs(newLayer.cels) do
+        app.activeFrame = cel.frame
+        app.command.Flip{ target="mask", orientation="vertical" }
+        cel.position = Point(cel.position.x,
+                             cel.position.y + 2*(bounds.y + bounds.height - spr.height/2))
+      end
+      app.activeFrame = oldFrame
+    end)
+end