Pixel perfect collisions for platforms

Question

i'm trying to do a pixel perfect collision but i don't know how to handle collisions when there is a jump . Here i have one image of a sample map:

But maybe I've done a bad supposing all pixel like little collision points . I mean , there is no differences between y-axis collision and x-axis collision in my collision map.

I have been treating each axis collision split , but that is bad done when diagonal jump have been made , cause you'll made an error in x or in y while correcting the position.

Then I thought that maybe I was wrong in my supposition that I didn't need to split for pixel collision type.

I will resume it in 2 questions:

• how can I handle pixel perfect collisions for a platformer?
• if I'm doing it well , How to manage the x-axis, y-axis problem?

P.S: My collision 'player' is a box way

Answer 1

There are different approaches you can use. For a start, I'd use a rather simple (maybe even a bit naive) approach:

You're essentially checking two points on your character for now:

• The position where he's standing (feet; actually a bit right below the character).
• The position of his head (head).

The character is then moved based on the following rules: - If feet is not solid, drop down. - While feet is solid, move up. - If feet and head both are solid, the character dies (squeezed). Ifheadis solid, stop vertical velocity/jumping. - Whilehead` is solid, move down.

Checking left/right works in a similar way. Doing this right will also solve stuff such as ramps instantly for you.

Reading through the poitns above, it should be clear, that you essentially "bounce" the character instead of having him standing still. This is true, but the player won't notice, because you don't draw inbetween these steps.