Show HN: A CSS-Only Terrain Generator

(terra.layoutit.com)

284 points | by rofko 13 hours ago

24 comments

  • senfiaj 10 hours ago
    When I turn off JS, it shows a loader instead of the terrain. Is this really CSS-Only? I mean it's still a high achievement even with JS, but was expecting it would also work without JS. This one, for example, truly works without JS https://benjaminaster.com/css-minecraft/ .
    • arbll 9 hours ago
      I'm assuming it's the render engine that is in pure CSS. You could display a static map in CSS but things like the tools to modify the terrain definitely need JS.
      • thih9 7 hours ago
        I wanted to check if your assumption is correct but I couldn’t find the source code.

        Why do you think the renderer is pure css and not e.g. mostly css?

        • embedding-shape 6 hours ago
          The top right button has a "Download code" which gives you a .zip file. That .zip file doesn't have any JS in it, and renders the terrain just like in the online editor, except you can turn off JS and it still works.

          Edit: someone else wrote basically the same an hour ago: https://news.ycombinator.com/item?id=45814791

          • thih9 6 hours ago
            Looks like it’s a “(css-only terrain) generator” - a generator that lets the user create and download a css only terrain.

            As opposed to a “css-only (terrain generator)” - a terrain creation studio built with css only.

      • psygn89 9 hours ago
        You might not need it using the new :has() and different inputs as modifiers. Though that's a lot of :has() and probably would kill performance.
      • nightpool 9 hours ago
        GP linked an example of a similar project that allowed you to modify the terrain without any JS at all
    • decimaldesign 8 hours ago
      I think what's intended is that the completed and downloaded solution doesn't require any javascript.

      Build something then hit the Download Code button - that packaged HTML solution doesn't require any javascript to render locally.

      • senfiaj 6 hours ago
        Yeah, it worked, it seems to be a static rendered html with no interactivity though.
  • forthwall 11 hours ago
    Wow this really feels like roller coaster tycoon!!! (I can see lots of people refer to this to their favorite sim game though)

    Great work!

    • yreg 9 hours ago
      I really miss these building games that used an isometric grid. RC Tycoon, Zoo Tycoon, Sim City, TTD, …

      Yes, it's less realistic, but it is so pleasant to work with. Everything you build aligns perfectly and if you want, you can neatly fill the entire map.

      In comparison, (even with many mods) my Cities Skylines or Planet Coaster creations never look quite right. Building the roads and paths is always awkward and frustrating.

      (I've commented this before.)

      • accrual 6 hours ago
        Starcraft and The Sims 1 as well! Games that would let one rotate the isometric view once blew my mind, it was like going from 2D to 3D.
    • andruc 11 hours ago
      Funny, my mind went to OpenTTD
      • mig39 11 hours ago
        Both Rollercoaster Tycoon and Transport Tycoon Deluxe (which lives on in openTTD) are by the same author, and use the same engine :-)
        • lawlessone 6 hours ago
          Chris Sawyer, he made them with a tiny magnet that he used to write the games directly to a hard drive.
          • brendoelfrendo 2 hours ago
            I once heard he tickled a butterfly in Brazil to cause a cloud in the UK that diverted a cosmic ray onto his hard drive in the exact right spot to flip the required bit.
      • hulium 8 hours ago
        The biome button graphics are taken from the OpenTTD main menu.
    • devmor 10 hours ago
      Reminded me quite a bit of Populous[1] as well.

      1. https://en.wikipedia.org/wiki/Populous_(video_game)

    • Igrom 10 hours ago
      For me, "Briefing" from Ace Combat 2 played back in my head straight away.

      https://youtu.be/5uPVGs7bq3s?t=8

    • worldai 10 hours ago
      This is exactly what I thought of
    • lawlessone 7 hours ago
      I like it's also really 3d, while looking like older 2.5d games.
  • cmiller1 11 hours ago
    Lots of javascript for a "css-only" tool. Looks like just the rendering is css-only.
    • jonahx 10 hours ago
      You can open up your terrain in codepen with nothing but CSS/HTML, and it renders fine. It's just not interactive / draggable anymore.

      So the JS is only being used, essentially, as a nice UI for configuring your terrain and the camera angle from which it's viewed.

      This is still an incredible feat.

    • bogwog 11 hours ago
      I guess it'd be more accurate to call it a "Generator for CSS-Only Terrain", as the generator itself is not CSS-only.
    • embedding-shape 11 hours ago
      Not to mention of all of those pesky HTML tags and images, clearly not CSS-only, what a fraud.
      • cmiller1 11 hours ago
        "CSS-only" colloquially tends to mean HTML and CSS without Javascript, sometimes without images.
        • DonaldPShimoda 11 hours ago
          The tone of the parent comment suggests they were writing in jest and are aware that "CSS-only" includes HTML.
    • MarsIronPI 11 hours ago
      Yep. Can confirm this does not work with JS disabled. I'm disappointed by the misleading title.
      • shermantanktop 10 hours ago
        is it a Generator for CSS-Only Terrain? or a CSS-Only Generator which creates Terrain?

        We need PEMDAS for English.

        • Elfener 10 hours ago
          Let's use sexpr?

          actual meaning -> ((CSS-Only Terrain) Generator)

          incorrect interpretation -> (CSS-Only (Terrain Generator))

          • shermantanktop 5 hours ago
            maybe RPN?

            actual meaning -> CSS-Only Terrain + Generator +

            incorrect interpretation -> CSS-Only + Terrain Generator +

            Really we may need BNF here

  • julius-fx 11 hours ago
    This is incredible - looks like SimCity 2000.
  • mpeg 12 hours ago
    Reminds me of Populous!

    Very cool

    • rofko 11 hours ago
      Thank you! Populous and Transport Tycoon were two big inspirations for sure :)
      • chubs 6 hours ago
        Also reminded me a lot of simcity 2000. Congrats, it's very neat!
      • drcursor 11 hours ago
        Next step Populous in only CSS + JS
      • johnh-hn 11 hours ago
        You nailed it. Well done!
    • johnh-hn 12 hours ago
      I just came here to say the same thing. The raise and lower tools in particular reminded me of it.

      For anyone who hasn't heard of it before: https://en.wikipedia.org/wiki/Populous_(video_game)

      • dylan604 11 hours ago
        You guys have sent me down memory lane. Hopefully, I don't forget when I have free time to search, but hopefully I can find this to play in an emulator somewhere. This was the very first game I ever bought even though I didn't have an Amiga but had one that was very accessible.

        edit: couldn't wait. did the search. it's very much available to play online. hello rabbit hole...

        • johnh-hn 11 hours ago
          Just in case you never came across it, I think the second game is much better than the first one. Enjoy the nostalgia trip!
        • linsomniac 10 hours ago
          Do tell, I've been wanting to play Populous again for a few years...
          • dylan604 9 hours ago
            dosbox top result in search
  • bodge5000 10 hours ago
    I've used a few terrain generators before but I think this one might be my favourite. Obviously the fact its a "CSS only" demo project restricts things a bit, but its got enough going for it regardless.

    It actually comes at a really good time for me, I'm currently trying to make the transition from 2d game dev to 3d and things like this are really helpful.

  • paulbjensen 10 hours ago
    Really cool, especially when I realised you could rotate the terrain and do some zooming as well.
  • em3rgent0rdr 10 hours ago
    Impressive, but there is a noticeable lag after modifying the terrain or moving the camera. Is there a way to know if the browser is using the GPU or CPU for rendering, and is there are way to see the milliseconds per frame?
    • bob1029 9 hours ago
      It looks like a layout/style/composition issue with the browser engine.

      In Safari I'm seeing 91% CPU time on paint, 6% on layout, 2% on styles. It looks like it's taking somewhere between 100-200ms on my machine to chunk through a state change each time.

      > Is there a way to know if the browser is using the GPU or CPU for rendering, and is there are way to see the milliseconds per frame?

      For Safari, you would go to the Web Inspector and navigate to the Timelines tab. Chrome has a similar thing.

  • RugnirViking 12 hours ago
    Really reminds me of openttd, especially the sandy border around the water

    Looks really cool and runs great on my phone.

    Seems like there's some kind of rendering bug in the corners sometimes causing the walls to intersect the grass

  • kataqatsi 5 hours ago
    for those interested in more CSS-Only art, Lynn Fisher makes some neat stuff

    https://a.singlediv.com/

  • w4yai 11 hours ago
    I got some rendering issues, but otherwise very cool !

    https://i.imgur.com/qT6ozyh.png

    Firefox 144.0.2, Windows

    • rofko 11 hours ago
      Thanks for the report! Are you using a dark mode extension by any chance? I’ve seen that happen with Dark Reader in Chrome.
  • throwaway2037 10 hours ago
    It is giving Sega Genesis "Populous" vibes.
  • ryukoposting 11 hours ago
    Dark Reader mutilates the rendered output, but only certain tiles. No clear pattern as to what tiles get mangled. Peculiar.
  • stefs 11 hours ago
    1. what's a layou tit?

    2. does it sometimes raise / lower by 2 units?

    3. the "flatten" tool is missing.

  • hersko 10 hours ago
    This is super cool! Wonder how hard it would be to use with an RTS game.
  • iagorodriguez 11 hours ago
    Amazing job by an amazing developer!
  • nefarious_ends 10 hours ago
    Very cool! Do you think it’s possible to do lakes and waterfalls?
    • rofko 10 hours ago
      Definitely! I'm planning for more landscape features for next versions. I think rivers will be a great addition, and waterfalls/rapids sound really interesting too. In the end it's a matter of adding a few classes and designing some sprites.
  • cluckindan 11 hours ago
    Nice! Now do collision checks ;)
  • robertheadley 11 hours ago
    This is really cool.
  • worldai 10 hours ago
    Impressive work
  • ModernMech 11 hours ago
    This thing is killing my CPU, what's the actual bottleneck here for CSS? Is it the number of elements visible and rendered at once? Is it the calculation engine backing CSS is super slow? Or just that most of the work is being done on the CPU it seems (on my machine, rotating around the map, my integrated GPU goes to 20% but CPU stays around 40-50%).
  • EGreg 11 hours ago
    Can someone please reimplement something like Warcraft 2 on a mobile web device?

    It would be a hit, I’m telling you. Even from 1995.

    Some people are still playing it 30 years later, obsessively.

    And myth ii by Bungie is a classic too

    • o11c 7 hours ago
      Stratagus has an android port at least ...
    • mock-possum 10 hours ago
      The controls would take some serious reworking to make it work on mobile - I could see adding a ‘pause’ feature to give you time to scrub your fingers all over the screen to issue all your unit and build orders, performant pinch to zoom would nearly negate the need for a mini map, lots of reworked GUI for building stuff and managing workers
      • EGreg 10 hours ago
        Anyone made a real-time-strategy engine for tiled games on mobile?
  • jimmydin7 12 hours ago
    looks sick! great job :)
  • OldGreenYodaGPT 11 hours ago
    Crazy that vibe coding can make things like this now! 2026 going to be crazy! There is no AI bubble