feat: directional bullet animation

[scarf005]

Summary

SUMMARY: Features "Directional bullet animation"

Purpose of change

• Resolves Improve bullet animation #1671

Describe the solution

• adds new sprite id "animation_bullet_normal_0deg" and "animation_bullet_normal_45deg" to handle directional bullets.
• previous sprite id "animation_bullet_normal" will be used as fallback if these new keys aren't found.

Describe alternatives you've considered

• determine bullet sprites by weapon category
• move some lambdas into headers?
• refactor int rota in cata_tiles.h into enums?
• can SDL handle 45 degrees rotation? if then no need for diagonal sprites

Testing

spawned m16 and fired at zeds. was able to render directional bullets with new tilesets and legacy bullet with old tileset.

[Coolthulhu]

One rather big problem: there is no fallback when the tile is not available and the tile is unavailable in current version of the UDP tileset.

The best way to solve this would be to fork boophis' tileset repo, add a tile there, compile the new tileset, then PR the compiled tileset - here or as a separate PR. Then PR the new tiles to tileset repo as well - having BN-only content won't break things, since it doesn't overwrite anything.

A minimal solution would be to provide fallbacks in all tilesets and tile config examples and manual addition of the new tiles to already-compile UDP. Still, the addition should be PR'd to the tileset repo as well, otherwise an attempt to update the tileset will remove the diagonals and have them show the "no tile found" tile.

[scarf005]

true, or how do you think about providing a hardcoded fallback for diagonal bullets first?

[Coolthulhu]

Hardcoded fallback would require good documentation for modders/tileset makers to know how to override it. Core examples would be better.

[olanti-p]

Is this still relevant?

1. There's a merge conflict, but it's trivial
2. There need to be either hardcoded fallback defined in C++ or dummy entries added to the tilesets so the bullets don't show up as symbols. The latter would be easier to implement, just find the entry in tileset's JSON that has "animation_bullet_normal" in it and extend it into an array [ "animation_bullet_normal", "animation_bullet_normal_diagonal" ] (or extend the existing array if there is one). This will make it use the same tile.
3. I'm not sure about the state of Boophis' unpacked repo, but a PR there would look like this
   Add sprite for mi-go nerve clusters (BN) Theawesomeboophis/UndeadPeopleUnpacked#41
   It's basically a JSON entry that describes the tile and the small PNG, both placed in the proper folder.

[scarf005]

yeah i'd love to see this get merged, will try continuing it tomorrow

[scarf005]

the PR's ready. old bullet sprite is used as fallback if it cannot find angled ones from tileset.
i'm unhappy with the unnecessary lookups on every frame but i decided to keep it since

1. lookups doesn't seem to be the bottleneck, the game literally searches for every single items with string key yet it keeps 60fps.
2. refactoring looks like nightmare to begin with. maybe after build: yet another C++20 migration #2341 gets merged and remove overloading whatsoever with designated initializer lists.

[scarf005]

regression found, fallback searching logic always returns false, keeping it draft until fixed.

nevermind, i was using symlinked gfx directory and hadn't updated the tileset there.

[olanti-p]

Fallback behavior works as expected.
Since updating UDP from Boophis'es repo is a bit problematic for now, I've pushed a patch to this PR that adds directional bullets to our own compiled version.