Text widget: intersect scissor.

Fixes a visual bug where text would display outside widget boundary.
Mved intersectScissor to Backend.

luigi/painter.lua

@@ -11,23 +11,6 @@ local Painter = Base:extend()
 local imageCache = {}
 -- local sliceCache = {}
 
-local function intersectScissor (x, y, w, h)
-    local sx, sy, sw, sh = Backend.getScissor()
-    if not sx then
-        return Backend.setScissor(x, y, w, h)
-    end
-    local x1 = math.max(sx, x)
-    local y1 = math.max(sy, y)
-    local x2 = math.min(sx + sw, x + w)
-    local y2 = math.min(sy + sh, y + h)
-    if x2 > x1 and y2 > y1 then
-        Backend.setScissor(x1, y1, x2 - x1, y2 - y1)
-    else
-        -- HACK
-        Backend.setScissor(-100, -100, 1, 1)
-    end
-end
-
 function Painter:constructor (widget)
     self.widget = widget
 end
@@ -198,7 +181,7 @@ function Painter:paintIconAndText ()
 
     Backend.push()
 
-    intersectScissor(x, y, w, h)
+    Backend.intersectScissor(x, y, w, h)
 
     -- draw the icon
     if icon then
@@ -237,7 +220,7 @@ function Painter:paint ()
         Backend.push()
 
         if widget.parent then
-            intersectScissor(x, y, w, h)
+            Backend.intersectScissor(x, y, w, h)
         else
             Backend.setScissor()
         end