Week 6 - Lay of the Land

No update for last week, between the Holiday and a few personal obligations, I didn't really accomplish much worth talking about. Mostly I just did some research into my next project goal; tile sets.

Turns out Godot has plenty of tools to make setting up tile sets particularly simple, and a bunch more tools to give you just about all the control you could need. So, armed with a bunch of new knowledge I started off this week by... realizing that the tile set sprites I found for Super Metroid were incomplete. Honestly, I'm finding more and more that the Super Metroid sprites that I have access to are far from the comprehensive collection that I had first thought they were. The GBA Metroid games on the other hand, have proven to be quite thorough. In this particular case, the sprites that I was missing were these little guys:

These represent tiles that can be destroyed by specific weapons from Samus' arsenal. For some reason, all of the sprite collections I could find for the Super Metroid tiles only had the tiles representing Speed Boost and Power Bomb blocks, and I did quite a bit of digging. Those ones up above are specifically the versions from Zero Mission, and since these are lower resolution than the tiles from the SNES, I've decided to just use the GBA tiles in general moving forward. I would do that same with Samus' own sprites to keep things consistent, but redoing all of the animations, let alone having to clean up and repair the sprite sheets would likely take more than a full work week by itself. If it bothers me enough as I continue through this project I'll consider revisiting the issue later, but for now we'll simply have to live with it.

Now, getting the tile sets working within Godot was actually pretty fast and easy once I found the sheets I wanted to use. I messed around a bit with setting up the auto-tiling tool with a few different terrain types, applied physics shapes to the individual tiles I was using, and then went about replacing the white block platforms of my test scene. Here are the results:

Definitely an improvement visually. As a bonus, I also figured out how to get slope movement working properly.

Usually that's a massive pain, good on Godot for having built-in systems to handle it. In any case, because getting the tiles in went so smoothly, I moved onto the "stretch goal" that I set myself for the week; tile destruction. This is something that I've been thinking over for a decent while, and I think I came up with a pretty decent solution. Tile maps in Godot are considered to be a single object, so no matter what tile a projectile hits, it returns the tile map itself as the object it hit, and the tiles themselves don't have any logic attached to them. That means that I can't attach any sort of "Destroyable" script to tiles that I want to be able to blast away.  Instead, I leveraged the ability to create multiple tile map layers, and I placed tiles on a second layer to signify both that they can be destroyed, and specifically what they can be destroyed by.

When a projectile registers a collision with a tile map, I get the coordinates of the tile it hit and see if a corresponding tile exists on the "destructible" layer.  If it does, I check to see if that tile can be destroyed by the projectile that hit it before removing the tile on both the "destructible" and "terrain" layers. I then spawn a pooled object that plays the tile destruction animation while also storing information about the tile in question, include what type of tile it was originally as well as whether or not it will need to reform after a few seconds (since that's a thing that happens sometimes in Metroid games).  Reformed tiles only show the "destructible" layer version of the tile, since that's how it works in the source material.

There's still some work to be done here, such as how certain weapons can reveal a destructible tile without actually destroying it, but that sort of stuff is probably going to have to wait until I actually get more weapons implemented. First though, I think I'm going to make my next goal getting a basic enemy working, that way we have something besides the ground to shoot at.

See you next time.