3D software is cool. also grass is insane

3D. I like 3D stuff. I also make 3D stuff. I use the free 3D software Blender to make all of my cool 3D scenes and stuff. (though you probably already know that from the about page) Knowing how to use 3D software is super cool, because if you want something, you can just make it. Want to make a super cinematic shot of a bottle? You can do that. Want to make realistic grass? You can do that. Want to make an animation of red and blue dorito bags fighting on the moon? You can do that as well.

I think enabling regular people like me to make 3D scenes is just so much power. Right now, I could open up Blender, and create realistic grass in roughly five minutes. Speaking of grass, do you know how hard grass is to render? No seriously grass is insane. To get good grass you have to have at bare minimum, 10,000 hairs per square meter! (fig 3) That doesn't seem so bad though, right? I mean, after all, there are lots of blades of grass in just one square meter. But let's look into what a blade of grass is made of. A single basic blade of grass is a tetrahedron with three faces. (bottom face not rendered) But a blade of grass isn't just that, it has to be tall, and curve a little to look realistic. So when you add a few loop cuts, in this case five, you get 18 faces. That is kind of a lot. So now we're dealing with 180,000 faces per square meter. Now you see how insane it is. For reference, the 3D title text that says "Tangets" has only 2,513 faces. That's 71 times fewer faces! If you know anything about computers, you know that the fewer faces the easier.

Since realistic grass is so hard to render, I've always wondered how people render huge fields of grass, specifically this (fig 4) Kane Pixels video. The amount of grass in this scene would drastically increase the render time, but I mean he's a producer I think so I guess he has a render farm or something.

When it comes to video games, I do like the approach of scattering a 2D grass image with a random Z rotation on the ground. I think that's probably the best and easiest way of rendering grass for video games. Take Scrap Mechanic for example. The grass is rendered in exactly this way, and grass further out is not rendered. To my knowledge, many games take this approach. It's kind of ironic, isn't it? One of the simplest things that everyone knows about, and yet we have so much trouble recreating it efficiently.
anyway thank you for coming to my talk ted.