Off-grid Copy

It seems June was Clipboard month. Just to close on that topic, there is one interesting thing we did with the clipboard I would like to introduce: Off-grid Copying. You may ask what is that, and more important, do we really want it.

Imagine you want to copy a piece of a scene you have done. Normally you would create a selection box and copy its voxel contents into the clipboard. The selection box can be resized, but so far, the selection boxes have been necessarily aligned to the world axes.  What if you could rotate the selection box?

It does bring up an interesting possibility. Now you can get any slice of an existing object, no longer you are constrained to the horizontal or vertical.

The following video shows this in action:



In this case we were just rotating a selection box. The really nice bit about this is, it does not have to be a box. It can be any arbitrary volumetric shape.

This opens up a new set of tricks. You could for instance make a statue. Then select the statue using a regular on-grid selection box and copy it into the clipboard. Now comes the trick: you could use the clipboard contents (the statue) as the selection scope. This would copy the voxels as usual, but their outside shape will still conform to the original statue.

Another way to see it, is you can perform boolean operations using the clipboard. What I like about the approach is it feels simple once you try it. You do not need to understand the "booleaness" of it all. Just like you can have circular or even free-shaped selections in Photoshop, you can have your selection take any form you need. Sweet!

Copy Paste Paste Paste

I did not see this one coming. I must thank players for showing me this: Old-school copy and paste helps a lot when you are building with voxels. Take a look at this screenshot of a Landmark build:

It many not be obvious at a first glance, but a lot of what you see here is the result of copying and pasting.

It is true that non-voxel edition systems also have copying, but I believe this is a very different mechanic. A voxel clipboard is a new thing.

When you paste objects in a mesh based system (like Maya, or a traditional game engine editor), you are cloning objects or creating instances of them. This is very cool and allows you to do many invaluable tricks, however, every time you paste a new object goes into the scene. If you paste overlapping an existing object they do not merge into one. In some sense, pasting in mesh systems does not help you build a larger thing. You build an assembly of things.

In mesh based editors you get a sense that every paste counts. The scene complexity grows every time you press that Ctrl+V. Yes you could stack some boolean modifiers and have any new pasted meshes in them, but this is getting complex now. My interest is systems anyone at home can figure out.

Copy-Paste with voxels feels organic. It is more like the clipboard in a word processor. You get things you like and combine them in a new form. Then you copy the new form and use it as an element of something else. All this time you are working on only one thing, it remains simple in your mind. You are not leaving a long trail of objects behind you.

One thing is certain, we are taking the clipboard very seriously now. Here is a video showing some new cool tricks we are able to do:



There are still aliasing issues, just like with our line tool, so some configurations may not paste back into pristine conditions. I think this is alright as long as you remain aware of what the limits are. And of course, our plan is to continue to bring down these limits.

New renderer

Our new deferred renderer is taking shape:

I like the water in particular. Still many features missing, like point lights you can move around. And I haven't given up yet on a realtime global illumination hack. I think this is mandatory today to make interior spaces interesting.

This seems a lot of work. Does it make sense to build your own renderer? My interests are more around content generation and management.

Having a custom renderer has some advantages. It makes it very easy to get any project going. Once this engine is packaged into some form of SDK, it will help that anyone can make changes, compile them and run them without any third party libraries (just the OS and OpenGL).

And then, looking at the problems you get when implementing a renderer gives you some perspective. That tiny pixel in the horizon should grow and become a fully volumetric rock. Understanding how these distant features can be produced by the shaders helps tie them down to their close-range volumetric representations.

Grammar Time

Yes, grammars. The last update had a hint of this, but here you can see them in more detail. As you probably know, we are building a repertoire of architectural grammars. The following video shows a few of them:



This set is geared towards medieval, fantasy settings, but I suspect most of these grammars would hold for a different theme.

This system becomes very interesting once you consider ending building blocks could be replaced by elements that tie closely to your project's vision. At any time you could replace the arches, columns, ornaments, even bricks, by custom components you may have sculpted earlier. What the grammar gives you is the order and structure of these prefabs, but the final look and feel can be pretty much up to you.

As you can see for the moment we are focusing on smaller grammars. You can think of these as smart brushes that will allow to lay walls, floors, bridges, even towers in the locations you choose.

While grammars are able to express entire buildings (even cities), I believe we need to start small and allow you to place these smaller elements following your imagination. Also there is little point in generating an entire castle if the building elements are not interesting enough. So we are making sure we have a solid repertoire of grammars before we take on larger things. Even something as simple as a basic stair tool can save you a lot of time.

As usual let me know what you think. I'm in particular interested in how many of these do you think we would need for a particular theme, how generic or specific they should be, what kind of parameters would you like to have as inputs.

Video Update for April 2014

Wondering what happened in the last few months? Here is an update:


There are several things we did that were not covered in this update. You will notice a river in the background but there is no mention about water.

It is not that we are hydrophobic or that we want to tease you about this feature, we just want to spend more time improving the rendering.

I also go on in this update about how clean and sharp our new tools are. There is indeed a big difference in the new toolset, but still there are serious issues with aliasing when you bring detail beyond what the voxels can encode. For instance, the line tool now can do much better lines, but we still cannot do a one-voxel thick line that goes in any angle. This is because in order to fix the aliasing in this line would need sub-voxel resolution. So it OK to expect cleaner lines, but they can still break due to aliasing.