Scissor Rect for director

[MattiaFortunati]

RNDirector should have scissor rect for each scene (to not overlap objects from different scenes than current one)

PROBLEM: other scissorRects applied to props will override the scene one, so the overlap bug will be persistent.

[Sylph]

For now we could also just loop through them, and move the individual scissorRects as well. It makes sense that when the screen is sliding out, the other scissorRects would move with the screen. It's what I'm doing for now.

The following in RNDirector:slideout is a rough way of how we can change it.

    if CURRENT_SCENE_GROUP ~= nil then
        local groupArray = { CURRENT_SCENE_GROUP }
        local movedScissorRectArray = {}
        local groupIndex = 1
        while groupArray[groupIndex] do
            local displayObjects = groupArray[groupIndex].displayObjects
            for i = 1, table.getn(displayObjects), 1 do
                local displayObject = groupArray[groupIndex].displayObjects[i]
                if displayObject.scissorRect and movedScissorRectArray[displayObject.scissorRect] == nil then
                    displayObject.scissorRect:moveLoc(-xx, -yy, 0, 0.001*TIME, MOAIEaseType.SMOOTH)
                    movedScissorRectArray[displayObject.scissorRect] = true
                end

                if displayObject:getType() == "RNGroup" then
                    groupArray[#groupArray+1] = displayObject
                end
            end
            groupIndex = groupIndex + 1
        end

        for i = 1, table.getn(CURRENT_SCENE_GROUP.displayObjects), 1 do
            if i == table.getn(CURRENT_SCENE_GROUP.displayObjects) then --call transition end callback only for last element
                trn:run(CURRENT_SCENE_GROUP.displayObjects[i], { type = "move", x = CURRENT_SCENE_GROUP.displayObjects[i].x - xx, y = CURRENT_SCENE_GROUP.displayObjects[i].y - yy, time = TIME, onComplete = slideEnd })
            else
                trn:run(CURRENT_SCENE_GROUP.displayObjects[i], { type = "move", x = CURRENT_SCENE_GROUP.displayObjects[i].x - xx, y = CURRENT_SCENE_GROUP.displayObjects[i].y - yy, time = TIME })
            end
        end
    end