source-engine/thirdparty/stb/docs/stb_voxel_render_interview.md

# An interview with STB about stb_voxel_render.h

**Q:**
I suppose you really like Minecraft?

**A:**
Not really. I mean, I do own it and play it some, and
I do watch YouTube videos of other people playing it
once in a while, but I'm not saying it's that great.

But I do love voxels. I've been playing with voxel rendering
since the mid-late 90's when we were still doing software
rendering and thinking maybe polygons weren't the answer.
Once GPUs came along that kind of died off, at least until
Minecraft brought it back to attention.

**Q:**
Do you expect people will make a lot of Minecraft clones
with this?

**A:**
I hope not!

For one thing, it's a terrible idea for the
developer. Remember before Minecraft was on the Xbox 360,
there were a ton of "indie" clones (some maybe making
decent money even), but then the real Minecraft came out
and just crushed them (as far as I know). It's just not
something you really want to compete with.

The reason I made this library is because I'd like
to see more games with Minecraft's *art style*, not
necessary its *gameplay*.

I can understand the urge to clone the gameplay. When
you have a world made of voxels/blocks, there are a
few things that become incredibly easy to do that would
otherwise be very hard (at least for an indie) to do in 3D.
One thing is that procedural generation becomes much easier.
Another is that destructible environments are easy. Another
is that you have a world where your average user can build
stuff that they find satisfactory.

Minecraft is at a sort of local maximum, a sweet spot, where
it leverages all of those easy-to-dos. And so I'm sure it's
hard to look at the space of 'games using voxels' and move
away from that local maximum, to give up some of that.
But I think that's what people should do.

**Q:**
So what else can people do with stb_voxel_render?

**A:**
All of those benefits I mentioned above are still valid even
if you stay away from the sweet spot. You can make a 3D roguelike
without player-creation/destruction that uses procedural generation.
You could make a shooter with pre-designed maps but destructible
environments.

And I'm sure there are other possible benefits to using voxels/blocks.
Hopefully this will make it easier for people to explore the space.

The library has a pretty wide range of features to allow
people to come up with some distinctive looks. For example,
the art style of Continue?9876543210 was one of the inspirations
for trying to make the multitexturing capabilities flexible.
I'm terrible at art, so this isn't really something I can
come up with myself, but I tried to put in flexible
technology that could be used multiple ways.

One thing I did intentionally was try to make it possible to
make nicer looking ground terrain, using the half-height
slopes and "weird slopes". There are Minecraft mods with
drivable cars and they just go up these blocky slopes and,
like, what? So I wanted you to be able to make smoother
terrain, either just for the look, or for vehicles etc.
Also, you can spatially cross-fade between two ground textures for
that classic bad dirt/grass transition that has shipped
in plenty of professional games. Of course, you could
just use a separate non-voxel ground renderer for all of
this. But this way, you can seamlessly integrate everything
else with it. E.g. in your authoring tool (or procedural
generation) you can make smooth ground and then cut a
sharp-edged hole in it for a building's basement or whatever.

Another thing you can do is work at a very different scale.
In Minecraft, a person is just under 2 blocks tall. In
Ace of Spades, a person is just under 3 blocks tall. Why
not 4 or 6? Well, partly because you just need a lot more
voxels; if a meter is 2 voxels in Mineraft and 4 voxels in
your game, and you draw the same number of voxels due to
hardware limits, then your game has half the view distance
of Minecraft. Since stb_voxel_render is designed to keep
the meshes small and render efficiently, you can push the
view distance out further than Minecraft--or use a similar
view distance and a higher voxel resolution. You could also
stop making infinite worlds and work at entirely different
scales; where Minecraft is 1 voxel per meter, you could
have 20 voxels per meter and make a small arena that's
50 meters wide and 5 meters tall.

Back when the voxel game Voxatron was announced, the weekend
after the trailer came out I wrote my own little GPU-accelerated
version of the engine and thought that was pretty cool. I've
been tempted many times to extract that and release it
as a library, but
I don't want to steal Voxatron's thunder so I've avoided
it. You could use this engine to do the same kind of thing,
although it won't be as efficient as an engine dedicated to
that style of thing would be.

**Q:**
What one thing would you really like to see somebody do?

**A:**
Before Unity, 3D has seemed deeply problematic in the indie
space. Software like GameMaker has tried to support 3D but
it seems like little of note has been done with it.

Minecraft has shown that people can build worlds with the
Minecraft toolset far more easily than we've ever seen from those
other tools. Obviously people have done great things with
Unity, but those people are much closer to professional
developers; typically they still need real 3D modelling
and all of that stuff.

So what I'd really like to see is someone build some kind
of voxel-game-construction-set. Start with stb_voxel_render,
maybe expose all the flexibility of stb_voxel_render (so
people can do different things). Thrown in lua or something
else for scripting, make some kind of editor that feels
at least as good as Minecraft and Infinifactory, and see
where that gets you.

**Q:**
Why'd you make this library?

**A:**
Mainly as a way of releasing this technology I've been working
on since 2011 and seemed unlikely to ever ship myself. In 2011
I was playing the voxel shooter Ace of Spades. One of the maps
that we played on was a partial port of Broville (which is the
first Minecraft map in stb_voxel_render release trailer). I'd
made a bunch of procedural level generators for the game, and
I started trying to make a city generator inspired by Broville.

But I realized it would be a lot of work, and of very little
value (most of my maps didn't get much play because people
preferred to play on maps where they could charge straight
at the enemies and shoot them as fast as possible). So I
wrote my own voxel engine and started working on a procedural
city game. But I got bogged down after I finally got the road
generator working and never got anywhere with building
generation or gameplay.

stb_voxel_render is actually a complete rewrite from scratch,
but it's based a lot on what I learned from that previous work.

**Q:**
About the release video... how long did that take to edit?

**A:**
About seven or eight hours. I had the first version done in
maybe six or seven hours, but then I realized I'd left out
one clip, and when I went back to add it I also gussied up
a couple other moments in the video. But there was something
basically identical to it that was done in around six.

**Q:** 
Ok, that's it. Thanks, me.

**A:**
Thanks *me!*