Painting on a waterproofing membrane

I've been trying to work out how to use an object (in this case a roller or a paintbrush) to paint colour over some text. I want the colour to appear over the text gradually, just as if it were being painted with the roller. I can move the roller along a motion path, but how do I paint the text?

I'd like to incorporate this into a quiz about waterproofing, where the learner paints their chosen answer and then hits submit.

Do I need a graphics package to do this?



2 Replies
Ned Whiteley

Hi Liz,

In the attached example I have created a slide with three possible answers and a paint roller (the Master Roller), which you drop on the answer of your choice. When you drop the roller, the following series of actions occur:

a. The Master Roller changes state to Hidden

b. The state of a roller next to your selected answer is changed from Hidden to Normal

c. The roller is moved along a motion path across the answer

d. The state of a 70% transparent yellow rectangle on top of the answer is changed from Hidden to Normal and its appearance on screen is controlled by a Wipe From Right animation that is timed to coincide with the movement of the roller.


For this to work correctly, you need to make sure that your animations and motion paths are correctly set up (also includes an Easing Direction of None -- see animation path options) and that the various components are in the right order on your timeline (e.g. roller above yellow rectangle).

Hope this is what you are looking for, but if you have any queries, just give me a shout here.