From time to time, people ask me how to “cut edges” in AC3D since the way AC3D handles edges is a bit different than other programs. Usually, I use the Divide Loop plug-in which is normally the fastest, easiest way to go. But, every now and then you get an edge that isn’t well suited for Divide Loop. In these cases, I use a combination of Insert Vertex and Slice Surface.

This video shows you how:

A QUICK SIDE NOTE: It is much faster to use the hotkeys (ctrl+shift+I and ctrl+shift+L) than it is to use the menus… the whole process can be completed in only a few seconds if you use the hotkeys. However, for the sake of clarity, I use the menus in the video so you can actually see what I’m doing.

The tiny little 320×240 render of the plasma for the POV-Ray tutorial was a bit hard to see, so I did a render in 1920 x 1080 resolution for those of you interested in seeing the details. It’s still a bit compressed, but the image is a lot clearer. You’ll find it here: download the video.

Enjoy!

POV-Ray has some very powerful commands for rendering realistic plasmas and explosions, but not very many people know how to use them well. This tutorial will show you how.

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Autodesk has a fun quiz on their site called the Fake or Foto test. In the quiz, you have to look at each image, and guess whether it is real or a render. Surprisingly, I aced it the very first time!

After I took the quiz, I went back and documented all the things that made me think a particular image was real or fake. That way I could see what it was that clued me so that I might improve my own work. In almost all cases, it wasn’t that the CG images were obviously wrong in any way, it was simply that the real images had more “detail” in them.

For years, the limitation has been what the software could do, but I’m not so sure that’s true anymore. In games especially, production costs have gone up as graphics have become more realistic simply because making detailed images is very time consuming. The relationship between time, money and graphics detail is linear. The problem, of course, is that neither time nor money are infinite. Limited budget means limited production cycles, which means limited time to spend adding things like scratches, scrapes and nose hairs. Eventually, we’ll reach a point where we can’t add more detail not because we’re out of RAM–we can’t add more detail because we’re out of time! Truthfully, I think we’re on the horizon of that already.

While I’m certain that there are still numerous improvements to be made in traditionally researched areas such as lighting, I think technological improvements to workflow have more potential to improve the quality of computer graphics in the near future than virtually any other area. Automated procedural geometry, better methodologies and tools that allow for less restrictive workflow patterns–such as recent advancements in re-topology interfaces–can allow us to complete the same job in less time and with far less effort. We know the artists and software can do it; now we need to make it practical.

For the curious, here are my impressions from the Autodesk quiz:

** WARNING ** Spoilers follow. You might want to take the quiz yourself before you read my analysis of the images.

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Ambient occlusion is a lighting technique that is commonly used to create soft shadows on objects. Ambient occlusion isn’t used to create the type of shadows that are cast from objects with a light shining directly on them. Instead, ambient occlusion generates the type of deep shadows that appear in the corners or creases of things, where it is hard for the light to reach.

Technically speaking, ambient occlusion is a global illumination technique. However, in common usage of the term it is often referred to as a cheap alternative to global illumination. To clear up any confusion, what most renderers refer to as “global illumination” is actually an amalgamation of several techniques such as radiosity, metropolis light transport, image-based lighting or photon mapping. The actual techniques used differ slightly from renderer to renderer. Some renderers include an ambient occlusion term as part of their global illumination calculation; others do not.

Like most global illumination techniques, ambient occlusion is dependent on the other geometry in the scene. Ambient occlusion on its own generates less realistic lighting than “full” global illumination. However, ambient occlusion is much faster and less complex to calculate than other methods which is why it is still popular among game developers and in production animation.

(Left) Without Ambient Occlusion. (Right) With Ambient Occlusion
Click for larger image.

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