Dark Streets Tech Demo 1
Hi all! Dark Streets is a first-person shooter, mechanically most similar to Wolfenstein 3D or Blake Stone, but also inspired by Doom, Blood, and Ion Fury. I have been slowly developing this game in my free time over the last year and a half. I referenced LoDev and a paper by Amanatides and Woo for some of the raycasting steps, but the rest of the code and graphics are mine. Enjoy a small preview!
Raycasting renderer
Since the setting of the game is a city, I specifically wanted to write a renderer that could draw tall buildings, short objects, doors, and interiors. I think I am pretty close.
- Pretty performant: Everything below takes up only 50-60% of CPU, unless you go crazy with geometry and distances.
- Fixed camera height: This makes walls look better. Originally, I had variable camera height and headbob, but that made textures a bit too jagged.Might reconsider based on performance later.
- Variable brightness: Based on distance, using draw palettes.
- Floor textures: Pretty basic, using horizontal TLINE
- Multiple floors! Normally, I see raycasters render just one floor (Caped Feline Arena and Anarch are notable exceptions), so this is a bit unusual, and it allows more interesting designs.
- Ceilings. Although texture-less, ceilings are rendered separately from the sky, and allow for features such as archways, underpasses, and building interiors.
- Animated doors: They are also rendered halfway on the tile to stand out from the walls.
- Z-buffer and clipped sprites: This piece is not very efficient yet, but works pretty well.
Gameplay
You can walk around, open doors, pick up and fire weapons (but can't defeat the enemies yet).
- Variety of objects: Solid obstacles, ceiling decor (can be walked under), floor decor (cannot be walked through, but can be shot over)
- Five weapons: Infinite pistol, shotgun, Gatling gun, flamethrower, and a rocket launcher (unfinished).
- One large level, hoping to keep it like that for final game. Might not be possible with number of objects per level.
- Health and weapon pickups.
- Weapon switching: When picking up a new weapon and when running out of ammo.
- Enemies: Basic move-aim-fire behavior, in beginning stages.
Known issues
- Looking through open doors is slow. This is due to calculations on which vertical slice must be rendered for the door on each ray.
- Adding many objects will slow the game down a lot, due to many visibility and collision calculations.
Thanks
Big thanks to other PICO-8 first-person games for motivation:
- Trial of the Sorcerer
- Caped Feline Arena
- Star Beast
- Whiplash Taxi Co
This is a truly fantastic "open world" tech demo... Would stairs (or other such magic) be possible in this? It looks like you're occluding rendering anything above a certain height, so I imagine you could do the opposite (e.g. find stairs, go up, set new minimum z-height)
> This is a truly fantastic "open world" tech demo...
Thank you!
> Would stairs (or other such magic) be possible in this?
I believe so, in a way. What I envision is this:
- When player walks up the stairs, head position gets higher
- When player head position is right above the first floor, player is teleported to an identical-looking "second floor" (somewhere else on the map)
- Now player is on the "second" floor, so move the head position to the bottom, as if player is still coming up the stairs
- When player walks all the way up the stairs, their head position is back at mid-height.
(I hope this made sense)
The biggest issue with multiple floors (or having the view above the first floor) is that it becomes difficult to calculate occlusions for sprites - I'd have to use a 2D z-buffer, and clip the sprites using that, which would probably be slow... Or there might be a clever way to do that using upper memory? I would need to think about it.
@yaky - this is looking good! Really interested to see if you can keep it a single map.
If you decide to investigate multi-floors, I would highly recommend https://www.lexaloffle.com/bbs/?tid=46713 by paloblancogames for an example of a 2D z-buffer (I have adapted this for my current project), as well as Zep's cast.p8 demo (for an example of the most stripped down multi-level raycaster). You won't be able to use your tline floors (I think), but with textured walls it might not be that noticeable anyway.
Thanks for the CFA shout-out too :)
> If you decide to investigate multi-floors, I would highly recommend https://www.lexaloffle.com/bbs/?tid=46713 by paloblancogames for an example of a 2D z-buffer
Thanks! That's one 3D game I remember seeing a while ago, but couldn't recall the name of.
> Thanks for the CFA shout-out too :)
I see you also made Cab Ride, which was one of the first games I played on PICO-8, it's super chill.
Excellent starting point.
As you realized, raycasting is a bit of a dead-end for complex features, totally biaised, but see how Doom did propose better answers to many of your questions.
what would make this more impressive would be for it to have jump feaatures, and replace moving to the side with press twise on left or right to move left or right. that way you can build with parkour, and have more fun on the map.
@YoungSauce, with the current engine, limited jumping is possible to implement (as long as head height does not get above the first floor). I thought of having jumpable gaps/platforms, but I think it would be difficult to do that in a good way. For parkour-like game, a multi-floor engine like Sally Neptune (mentioned above) would work best IMO.
@yaky i was mainly thinking more floors, so there was a bit of exploration to it. and jumping u can duck enemies.
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