Posts Tagged ‘render’

AC3D Plugin: Material by Crease Angle and Planar Map by Material

Monday, June 15th, 2009

Two new plugins today!

The first plugin, Set Material by Crease Angle, sets the materials of a model based on the crease angle of the mesh. For each selected area, the plugin creates a new color in the palette and “flood-fills” the area until the angle between the surfaces exceeds the crease angle of the mesh. The result is that contiguous areas are all set with the same palette material, and a new material is applied wherever a discontinuity occurs. This allows you to easily break a model into sections along its creases for easier texture mapping, or many other purposes.

The second plugin, Planar Map by Material, actually includes three new commands.

The first command is Fit UV Coordinates to Map. This command is essentially the same as the “max” button in the TCE, forcing all UV coordinates into the 0-1 range, but unlike “max” this scales the map proportionally instead of independently on each axis.

The second command is Adjust UVs for Bilinear Filter. This is useful for game developers. This command scales your texture coordinates by a ratio of 240/256. The purpose is to create a small seam along the edge of the texture map so that if your game is using mipmapping with a bilinear or trilinear filter, the texture won’t bleed into its neighbors in your texture cache nor will it bleed into itself if you haven’t clamped the edges.

The last command, Planar Map by Surface Material, is probably the most useful of the three. Planar Map by Surface Material applies a “best fit” planar projection to all surfaces grouped by material in the current selection. If you section your model by material, this will treat each material color as a contiguous group and apply whichever planar projection fits it best in the TCE. You’ll still need to do some manual adjustment after you map it this way–especially texture packing, as this leaves plenty of room between areas so the surfaces aren’t too difficult to select–but it can save a lot of time in laying down a base mapping before you manually refine each area.

More information about each plugin is available in the readme.

Download the Material by Crease Angle plugin. (Requires Windows XP, AC3D 6.2 or above.)

Download the Planar Map by Material plugin. (Requires Windows XP, AC3D 6.2 or above.)

Rendering Plasma in POV-Ray

Friday, January 25th, 2008

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.

[youtube: 350 292]
An turntable of a plasma cloud rendered in POV-Ray
UPDATE: download the high-res version


Why Researching Workflow Matters

Friday, November 30th, 2007

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.