Show HN: A CSS 3D Engine (no WebGL)
github.com80 points by rofko 12 days ago
80 points by rofko 12 days ago
Over a weekend about a decade ago, I toyed with making a Final Fantasy Tactics-like game in the browser using CSS for the renderer. I could not get it to work in the time I gave it. I realized too late I needed to make some abstractions and stop trying to manipulate CSS directly.
Which is a long way of saying I appreciate how challenging this probably was to figure out. I love stuff like this.
But why not use WebGL? It's widely available, more efficient, and can render at a much higher quality.
Hi there! This is not trying to be a three.js replacement, scenes with huge polygon counts naturally should render in canvas.
For me, the interesting case is smaller low-poly or voxel scenes where loading a full 3D stack may be overkill, and where keeping the scene in DOM/CSS gives you easier integration with normal layout, styling, events, etc. Once you have the HTML, you don't even need to load the library to render a static model.
Also, part of the experiment is testing the browser’s limits and getting a clearer sense of where this approach works, where it breaks down, and what the tradeoffs are.
Cheers!
ha, so you could run this on the server and send down a page with no javascript at all? (with, i assume, a static camera only.) that's fun. i mean, you could also just render the model to an image at that point, but still, this is neat.
You can have a dynamic camera with 3D CSS only and no JS. The trick is move the scene instead of the "camera". CSS Doom uses this technique (although unlike the project I'm working on, it relies heavily on JS for the interaction logic).
Then there's "minecraft in CSS" which uses invisible form elements for camera rotation and works with no JS at all.
https://benjaminaster.com/css-minecraft/
It's been on HN before ( https://news.ycombinator.com/item?id=44100148 )
Yes, you can render on server and if you include CSS transitions/animations, you get an animated 3d render without the need for JS !
We haven't built it yet, but its on the roadmap
I'm all for experimentation but getting rid of JS in this case almost certainly results in worse performance. You're trading a bit of load time for significantly slower runtime/rendering.
Huh.... why would a CSS animation of a transform be slower than JS? This is strictly for the "CSS transform" case ofc - obviously pure webgl would be way faster.
I'm having a hard time seeing it. My experiments with CSS animation have always performed much better in CSS than JS (again, excluding it being pure webgl/canvas JS).
And ofc there's the nice bonus that it works if I haven't chosen to trust and whitelist their website for JS yet.
I meant slower vs. WebGL rendering, which requires JS. Each triangle is rendered as a DOM node. There can be thousands of triangles in a single model.
The gallery has been updated with more models. Compare the same model in PolyCSS vs. Three.js:
https://polycss.com/gallery/?model=205023689 (13 fps)
https://threejs.org/examples/#webgl_animation_skinning_morph (60 fps)
Oh. Sure, that is pretty obvious. A triangle in webgl is so much more lightweight than building it out of DOM elements but this was more about "if one is going to use this CSS system, why not support a pure CSS viewing mode" - which right now, it does not - rotation requires JS and is pretty stuttery. I was thinking it should actually be a bit smoother if there was a "toggle on/off rotation using a CSS animation" option. Plus, something like that could easily be done in pure CSS if JS was disabled, which would make the output all the more accessible and offer a good usecase.
It could also be helpful in scenarios where JS is restricted - emails? iframes? bulleting board user content? Dunno. Trying to come up with some that aren't just "nemo was running umatrix and doesn't trust your site just yet"
It's like transcoding a video into a GIF so that it can render everywhere. It will probably work but it's not really a serious option.