Question

I’m trying to make a game that will have a black screen, when you swipe the screen, the black portion you touch will disappear and show a image behind it. The object is to keeping swiping until you can guess what the image is.

I have seen other apps that do this. I’m stuck on how to do it. My idear was to modify a bitmap by changing the pixcels to see through. But I don’t see any way of getting access to the bitmaps memory, or maybe there is another way to do this????

Answer 1

One way to make this would be having your bitmap drawn like any other image, and on top of it you’ll have an editable black bitmap (that you can dinamically make using draw(), look for documentation on Paint class), and when the user swipes, you record the path, and use a brush to paint transparent pixels on the black bitmap, so the image below will become visible.

That last part is almost the same as implementing a simple paint app, so it shouldn’t be hard to figure out.