Left/right sprite flipping in iso mode. Run and crouch overlay. Minor extras.

[AnthonBerg]

• add isometric branches to facing-left/facing-right calculations for monsters and player (including actions and ranged). The calculations are reasonably simple and fast.

• enable sprite flipping in isometric mode when appropriate

• clarify to-flip-or-not-to-flip code for right/left-facing stuff

• flip all entity and overlay sprites in hitbutton_iso so they are facing right like in all the other tilesets :)

• add run and crouch tile overlay support

• add run and crouch overlay tiles to hitbutton_iso tileset

• add parameter comments to some function calls that have many parameters

• sneak brainless zombie sprite into hitbutton_iso tileset

• bonus: unshadow a couple of variables in a big tile-drawing function (x, y, col)

Summary

SUMMARY: Interface "Left/right sprite flipping in iso mode, run and crouch overlay"

Purpose of change

Until now it has only been in non-isometric mode that sprites have been flipped right/left to match orientation. Here's an attempt at addressing that. Run and crouch sprite overlay support is also added, as well as tiles to support it in hitbutton_iso.

Describe the solution

Added simple and fast logic to get the left/right movement in isometric space. Added iso logic to sprite-orientation draw calls to allow horizontal flipping. (Still no rotation or vertical flipping in iso mode.) Clarified some code a little bit too.

Also flipped all entity sprites in hitbutton_iso to be RIGHT-facing instead of left-facing. All the other tilesets have right-facing sprites out of the box.

We also add a RUN and CROUCH overlay tile support.

Plus some comments and cleanup, and a brainless zombie sprite.

Sending this in as one big pull request. My apologies. Thanks for your patience. The thing is that because of the sprite flipping that was required for hitbutton_iso, untangling this into separate PRs was a noticeable amount of hassle. The work came about in a long hacking session. Maybe this is all decent enough to be accepted as-is? If it's hard to work with this PR as is I'll rework it. Thanks.

I see these as only small changes that bring out the expressivity that's already in the engine. L/R facing sprites, sees-player alerts, and run/crouch overlays add A LOT to the gameplay in isometric mode.

Additional context

Screenshots:

Little computer person running to the left with lots of zombies approaching from both sides. Most of the zombies see the player, except some brainless zombies.

Little computer person crouches behind a road roller. Most of the zombies don't see us anymore.

[kevingranade]

This pull request has been mentioned on Cataclysm: Dark Days Ahead. There might be relevant details there:

https://discourse.cataclysmdda.org/t/tileset-editing-with-imagemagick-jq-fish-clion-and-pixelmator-pro/20228/13

[kevingranade]

Nice, minor thing, needs astyling.

[SomeDeadGuy]

Yes, thank you! This is something i wanted for a long time!

[AnthonBerg]

Thanks for the kind words! – I am undeserving as I keep forgetting to astyle! :) I am full of ambition to improve my citizenship. I'll fix!

(The chipper tone here is due to recent consumption of coffee (hot) and not intended to be sarcastic :) )

[AnthonBerg]

There we go!

I also notice that my Summary line could be improved – thanks Night-Pryanik! :)

[Night-Pryanik]

You are welcome!

[ZhilkinSerg]

@AnthonBerg Yeah, not is a standard C++ operator synonym, but https://stackoverflow.com/questions/24414124/why-does-vs-not-define-the-alternative-tokens-for-logical-operators.