Delphi custom animation - collision detection

Question

I\'m working with custom drawing / 2D animation and I\'m trying to figure out how to detect when the moving object collides with a wall in the map. User holds arrow keys on

Answer 1

I had already half-way answered my own question in the question its self. One thing I had thought of was reading the pixels of the image in the direction of the movement, and check if there's a line there or not. I now realize that I can have an extra layer under the FBMap map layer for the background, and leave the map layer as it is with only the collidable walls drawn.

When moving, scan the pixels in the direction of the movement on that particular layer, not the full image. Since I already have a pre-drawn layer sitting there, I can read it rather than the main image. Based on the speed of movement, I only need to look so many pixels ahead (at least a few more pixels than the number of pixels of movement).

Also, in case the background of the image has a picture representing the walls rather than straight plain lines, then this layer doesn't even have to be drawn at all. This layer can be explicitly used just for scanning a few pixels ahead of movement for collision areas. As a matter of fact, since I also need to recognize collision with other moving objects, I can draw all the objects on here as well (in black/white).

A few iterations of pixels across a canvas, for example 20, is nothing compared to extensive iterations through the map lines, for example 2000.