Show HN: A CSS-Only Terrain Generator

(terra.layoutit.com)

232 points | by rofko 7 hours ago ago

70 comments

  • senfiaj 4 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 4 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 an hour 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 39 minutes 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 25 minutes 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 3 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 3 hours ago

        GP linked an example of a similar project that allowed you to modify the terrain without any JS at all

    • decimaldesign 2 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 32 minutes ago

        Yeah, it worked, it seems to be a static rendered html with no interactivity though.

  • forthwall 5 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 4 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 38 minutes 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 5 hours ago

      Funny, my mind went to OpenTTD

      • mig39 5 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 20 minutes ago

          Chris Sawyer, he made them with tiny a magnet that used to write the games directly to a hard drive.

      • hulium 3 hours ago

        The biome button graphics are taken from the OpenTTD main menu.

    • devmor 4 hours ago

      Reminded me quite a bit of Populous[1] as well.

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

    • Igrom 4 hours ago

      For me, "Briefing" from Ace Combat 2 played back in my head straight away.

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

    • lawlessone an hour ago

      I like it's also really 3d, while looking like older 2.5d games.

    • worldai 4 hours ago

      This is exactly what I thought of

  • cmiller1 5 hours ago

    Lots of javascript for a "css-only" tool. Looks like just the rendering is css-only.

    • jonahx 4 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 5 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.

      • tantalor 4 hours ago

        It's a "(CSS-only Terrain) Generator", not a "CSS-only (Terrain Generator)"

    • embedding-shape 5 hours ago

      Not to mention of all of those pesky HTML tags and images, clearly not CSS-only, what a fraud.

      • cmiller1 5 hours ago

        "CSS-only" colloquially tends to mean HTML and CSS without Javascript, sometimes without images.

        • DonaldPShimoda 5 hours ago

          The tone of the parent comment suggests they were writing in jest and are aware that "CSS-only" includes HTML.

    • MarsIronPI 5 hours ago

      Yep. Can confirm this does not work with JS disabled. I'm disappointed by the misleading title.

      • shermantanktop 5 hours ago

        is it a Generator for CSS-Only Terrain? or a CSS-Only Generator which creates Terrain?

        We need PEMDAS for English.

        • Elfener 4 hours ago

          Let's use sexpr?

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

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

  • julius-fx 5 hours ago

    This is incredible - looks like SimCity 2000.

  • mpeg 6 hours ago

    Reminds me of Populous!

    Very cool

    • rofko 5 hours ago

      Thank you! Populous and Transport Tycoon were two big inspirations for sure :)

      • drcursor 5 hours ago

        Next step Populous in only CSS + JS

      • johnh-hn 5 hours ago

        You nailed it. Well done!

    • johnh-hn 6 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 5 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 5 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 4 hours ago

          Do tell, I've been wanting to play Populous again for a few years...

          • dylan604 4 hours ago

            dosbox top result in search

  • bodge5000 4 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 5 hours ago

    Really cool, especially when I realised you could rotate the terrain and do some zooming as well.

  • em3rgent0rdr 4 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 4 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.

  • throwaway2037 4 hours ago

    It is giving Sega Genesis "Populous" vibes.

  • RugnirViking 6 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

  • w4yai 5 hours ago

    I got some rendering issues, but otherwise very cool !

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

    Firefox 144.0.2, Windows

    • rofko 5 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.

  • ryukoposting 5 hours ago

    Dark Reader mutilates the rendered output, but only certain tiles. No clear pattern as to what tiles get mangled. Peculiar.

  • stefs 5 hours ago

    1. what's a layou tit?

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

    3. the "flatten" tool is missing.

  • hersko 5 hours ago

    This is super cool! Wonder how hard it would be to use with an RTS game.

  • iagorodriguez 5 hours ago

    Amazing job by an amazing developer!

  • nefarious_ends 4 hours ago

    Very cool! Do you think it’s possible to do lakes and waterfalls?

    • rofko 4 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 6 hours ago

    Nice! Now do collision checks ;)

  • worldai 4 hours ago

    Impressive work

  • robertheadley 5 hours ago

    This is really cool.

  • ModernMech 5 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 5 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 an hour ago

      Stratagus has an android port at least ...

    • mock-possum 5 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 4 hours ago

        Anyone made a real-time-strategy engine for tiled games on mobile?

  • jimmydin7 6 hours ago

    looks sick! great job :)

  • OldGreenYodaGPT 5 hours ago

    Crazy that vibe coding can make things like this now! 2026 going to be crazy! There is no AI bubble