Just working on tile collision and thought I'd share my method for people curious on how to do tile physics. There is a map class that takes care of the collision. The heart of it is the customizable callbacks called the preSolve and postSolve. With the callbacks, you can do neat things like one way tiles in the example. Collision detection is done by using the edges of a bounding box as vertical or horizontal sensors.
I know there's plenty of tile collision examples, but I wanted to post one with minimal amounts of code
Things to do:
* Slopes
In the demo:
Try changing the tile size or player box size! It'll work for any size! Try defining your own custom callback for neat stuff like destructible tiles or bouncy tiles.
Update! It now supports slopes and continuous collision detection. Syntax is similar to my lib: ATC, except you don't need Tiled. Just feed it a grid structure and a table with tile properties. Modify it however you want!
The difference in methodology from the posted links is that my sensors are the actual box edges so it's possible to miss tiles completely contained with a rectangle. This shouldn't be an issue when character movement is small enough for a sensor to catch collision tiles.
Slopes and curves are handled like retro games: Store an array of height values per slope tile. How the player reacts to the tile and the direction he needs to be pushed to resolve the collision depends on which sensor touches it.
I took the route of using the box corners to resolve slope collisions instead of the midpoints of each side. This has the problem of a character sticking out from a slope more instead of looking like he is standing on it with his "feet". Many old games covered this up visually by extending the slope.
lieudusty wrote:Are slopes implemented yet? I can't figure out how to make one.
Here's an updated demo with the slopes. Each slope tile has an associated height map that determines the shape of the slope. It's similar to the Sonic physics link.
I updated the module to version 3. You no longer have to create a box object. Instead, you create a handler object and pass the dimensions of your box to it for collision resolution. A lot of extraneous functions were also removed. It's much more flexible now so it should work with any map format, even Advanced Tiled Loader.
Hey, your collision detection is amazing but I'm not used to using entities, so could I ask how you'd bound images to an entity like you've made and then apply physics to it? I've essentially got code that doesn't have collision detection but can use images as the player character and has gravity applied to it, then there's this code that has great collision detection but I don't know how to change the player from a square to an image or how to apply gravity to it, so that it works the same way as a traditional platformer.
