COVERING OUR TRACKS July 2007
by John Mantzefield
copyright 2007

This months cover was created with Cinema4D XL v8.5 from Maxon.com. The modeling functions that were used to make the cover scene were for the most part described in my other recent COT articles. The primary difference between this cover image and the others is that all of the surface texturing and shading of the objects in the scene were accomplished through the use of Procedural texture maps. After the shapes of things are created for a scene and positioned in 3D space the next step is to apply colors and/or textures to their surfaces. This process is usually called surface or texture mapping. Cinema4D has three methods of creating these surface maps: importing photos (pictures of surfaces like a brick wall or tree trunk), using BodyPaint (a built-in paint program for painting directly on 3D objects), and procedural mapping.

PICTURES FROM MATH FORMULAS
Procedural texture mapping employs algorithms, which are defined as “an explicit set of rules for solving a problem”. While this is interesting background information for the 3D artist it doesn’t explain how to complete a project. All digital images are stored on a hard drive as a file that’s made up of numbers, so it follows that if you want to change the picture, just change the numbers... that’s what the algorithmic mapping function in a 3D program can do. In actual practice there are no math formulas visible in Cinema4D, just dialog boxes with sliders and percent or amount fields that you can change to get different images that are shown in a preview window. C4D Comes with dozens of procedural mapping shaders and other effects, and there are many others that can be downloaded or purchased commercially.

cot_july-07-1
If you look closely at the cover image’s surfaces you will see what looks like coarse and polished Stone, dark colored glass and mental surfaces. The image on the left Shows how a single procedural texture can be used to achieve a variety of effects when it is applied to the different surface material mapping channels. The image to the left shows how a procedural map that looks like the one in the next image below at top right would appear when it’s applied to the model. In the image to the left at ”B” the same map was applied to the Diffusion channel, in “C” it’s applied to the Transparency channel and in “D” it was applied to the Bump channel.


cot_july-07-2
The image to the left Shows approximately one-third of the procedural textures supplied with C4D. Each of these textures has several menu adjustments that allow you to produce a large variety of maps. In addition to this variability the texture maps can be applied one on top of the other in a manor which is very similar to Layers in Photoshop.

LEARNING CURVES & TECHNIQUES
One of my goals in writing these articles is hopefully to clarify what may seem like a bewildering field of endeavor. While many of the programs I’ve mentioned are complex and take time to learn, it’s worth it because this achievement frees the graphic artist to create whatever you can imagine. To help you along the path I’ll include a resource list at the end of the article.
cot_july-07-3
If you’re working with 2D imaging tools like Photoshop, Elements or Painter you can create stunning backgrounds (for photos or web site graphics) and masking effects (for decorative boarders) with the procedural functions in those programs. All of the numbered pictures the images to the left (except 1) Were created with Photoshop CS2. To create these pictures filters and other Photoshop functions require an image to apply their opreations to. The kind of image you’ll need varies depending on the filter or function - some require only a solid fill color, while others work best with a graduated range of colors or on a photo. One interesting technique is to take a photograph and apply Filter>Blur, then choose Gaussian Blur to get an image to apply a filter to. Another way to get an interesting base image is to put two or three images in a Layer Group and shift the Transfer Modes of the top Layers until you get something interesting.

IMAGES FROM FILTERS
Here’s the details on what’s depicted in the image above. Number 1 is a C4D material texture map from a free set of materials called Shader Club. In number 2 I started with a gray filled Layer, then applied the Filter>Noise>Add Noise and in Distribution choose Gaussian. Then with Filter>Blur I applied a Gaussian Blur. The brushed metal effect in number 3 was made from a horizontal Graduated background that had two shades of gray. I applied Filter>Noise>Add Noise and in Distribution choose Gaussian. Next I added a Filter>Blur>Motion Blur and set the Angle to 0. In number 4 the filter effects were made with the Filter>Pixelate>Mezzotint filter where the left area uses Coarse Dots, the center uses Short Lines and the right area uses Long Strokes. Number 5 was made with the Filter>Pixelate>Pointillize filter, then the Image>Adjustment>Levels was used to increase the images contrast. Next the right half had the Filter>Blur>Motion Blur applied with the Angle set to 0. The Filter>Render>Clouds was used in number 6. This filter uses the current Foreground and Background colors (you don’t apply this one to an image), and here the right half had the Image>Adjustment>Levels applied to increase it’s contrast. The Cloud filter can be used to create a mottled background similar to those used in portrait photography. Try making a backgrounds from two or three layers of Cloud patterns and combine them using various Layer Transfer Modes. In number 7 the filter I applied was the Filter>Render>Texture Fill where you choose a grayscale image. Here I used two grayscale images supplied with CS2 for Lighting Effects. And finally in number 8 the filers that were applied are found in Filter>Sketch where two types were used: Graphic Pen and Halftone Pattern.

RESOURCE LIST
DVD/CD tutorials from the following vendors allow you to watch the lessons on your Mac as professional instructors teach you how to use your software.
macacademy.com - Mac Academy - A wide range of titles
photoshopvideos.com - Reasonably priced training for Photoshop
totaltraining.com - An Adobe products training company
vtc.com - Virtual Training Inc. A wide range software titles
---------------
MAGAZINE SUBSCRIPTION LIST
cameraarts.com - An art photo magazine
layersmagazine.com - Adobe products how-to and reviews
pcphotomag.com & popphoto.com - general digital photo topics and reviews
digitalphotopro.com - bi-monthly pro photo magazine
---------------
DIGITAL PHOTO / CAMERA RESOURCES
steves-digicams.com - Steve’s Digicams is one of the best review and resource sites
dpreview.com - Digital Photography Review is another good review and resource site
photosolve.com - Photosolve makes high quality digital camera LCD screen viewers
bhphotovideo.com - B&H Photo is one of the best all around photo and electronics suppliers on the web
bogenimaging.us - Bogen is a distributors of Gitzo and Manfrotto tripods and more
prophotosupply.com - Local photo supplies from Pro Photo Supply - 1112 NW 19th - 503-241-1112