Project 2 : Shading

Due Date:
Tuesday, April 20: Bring sample of second material to class.
Tuesday, April 27: Critique

Reading: Chapters 5 and 8 (Kerlow)

To get started with shading in Power Animator, here are some tips.

To get started using RenderMan, look here.

In the Alias tutorial books, do the lesson titled Shading.

This assignment has 3 parts. Everyone will use the same camera and lights. Copy the file /home/cse458/data/proj2_setup to your wire directory (or just open it from Alias and save it to your wire directory). Import your model into this file.

1. Polka Dots

Cover each model with polka dots. The polka dots may be any size, but should be uniform in size, shape, and distribution on each model. They should also still look like polka dots. Here are a few ways to approach this problem:

1. There is a template polka dot pattern available: /home/cse458/data/polka.rgb. This texture tiles fairly well, but feel free to make your own. Alias provides several texture mapping options.

2. You might paint a polka dot texture that is warped so that it looks correct on your model. You can paint textures using whatever paint program you like. There is a painting application on the SGIs that you can start by typing paint at a UNIX prompt. You can also use Photoshop on the Mac in the smaller lab. See Tips below for more information about using Photoshop and the scanner.

3. StudioPaint is a 3D painting application that lets you paint textures directly on your model. To start it up: studiopaint, or select Utilities->studiopaint from the Power Animator menu.

2. Photorealism

Shade your model so that it looks exactly like the real object. Pay special attention to dents, smudges, scratches, and other "defects": it's often these details that make a model look real.

3. Effect.

Do one of the following:

(a) Second material. Make your object look like it's made of some completely different substance. (For example: leather, aluminum, terra cotta, Saran Wrap, matzoh, cork, terrycloth, papier mache, mosaic tile, vinyl, felt, skin, you name it.)

(b) Antiquity. Make your object look as if it has aged by a hundred years.

If you choose option (a), be sure to bring a real sample of your second material to class on Tuesday, April 20.

---

What we're looking for

We have different expectations for the results of each part of the assignment. The goal for the first part is polka dots that are round and evenly spaced, by whatever means necessary. This can be a lot harder than it looks, so just do your best. In the second part, you should emulate reality with all of its imperfections. Convince us that it's the real thing. In the third part, you should aim to convey the stated effect as well as possible. No cheating. ("Here you see my pepper grinder made out of... well... what does it look like to you? ... Mashed potatoes? Yeah, that's what I was going for.")

Since we will only see one view of the scene for each part (or all parts, if you like) of the assignment, take the time to position your model so that the best features are visible. We would like you to render your images using the camera we've given you in the setup file. (Remember that every time you change your view in the perspective window, you are actually moving the camera). It will be good practice to position and scale your object so that it looks good with the existing camera (since moving the camera may not be your resposibility for the final project). The final scenes should be rendered using the real render (as opposed to quick-render) option.

We'd also like you to use only the lights we've given you. Be sure to delete any duplicate or extra lights, as they can make your image look washed out. You may make slight adjustments to the positions of the lights if it will help illuminate a particular feature of your object, but try to keep the changes to a minimum. There will be plenty of room to use light creatively in the next assignment.

Your finished pictures should look roughly like this (with your object in place of the blue sphere, of course):

---

Turn in

Before the critique on Tuesday, hand in your project as follows:

1. Make a directory in /home/cse458/critique/shading with name that says something about the general scene (i.e. antique_shop).

2. In the new directory, put the following:
   1. Three high-quality rendered images (at a resolution of 720x486), one for each part of the assignment, named username_polkadot.rgb, username_photoreal.rgb, and username_effect.rgb. When you render a scene in Alias, the image is saved as a pix file (the Alias image format) in the pix subdirectory of your project. To convert this image to an rgb file:
      % fromalias myscene.pix myscene.rgb.

3. Make sure that the directory and files are world readable.

---

Tips

Where do you find interesting textures?

Look around on the Alias 3DCD (located at /usr/aw/3DCD). We would really like people to do their best job in making the textures look exactly like the object. If you are making a rock, make sure you don't just use a pre-packaged texture unless it is very close to the real texture.

You can scan images and objects in to PhotoShop on the Mac in the smaller lab. The fish texture in Fish Schtick was made by putting a real fish on the scanner bed! (Try not to make too much of a mess though...) You can also create textures from scratch using PhotoShop. Or you might want to modify an existing texture (changing various things like contrast, color, etc). For anything you do on the Mac, you will have to transfer your files to your SGI account. There is a program on the Mac called Fetch that will do this. If you need help using the Mac, please ask a TA for a demo during their office hours (or ask your classmates).