From: Jeff_Holinski@mindlink.bc.ca (Jeff Holinski)
Subject: Re: Imagine 2.0: Bad graphic quality??!
Organization: MIND LINK! - British Columbia, Canada
Date: Mon, 23 Nov 1992 02:28:33 GMT


The reason your sandstone won't stay still is that the roughness you're using
is a random thing. It randomly dithers the mountain to make it look rough.
To get roughness that will animate try this:
1: make a plane and set it to maximum roughness.
2: render an image of it looking straight down on it from above with a light
source to one side.
3: The image you get will be suitable for an altitiude map. Basicly you want
a full screen image of randomly dithered greyscales. You might be able to get
suitable results from DPaint's airbrush.
4: Select your mountain and go into the attribute window and select brush and
set the map type as an altitude map. Also select mirror and repeat.
5: Save the object and test render it.
6: Roughness on the mountain should be set at 0 before it's saved.

Since the object's roughness is now handled by an altitude map instead of
randomly you should be able to animate it properly now.
A couple of other things to try for better renderings are:
Set you quickrender to quarter-screen ham. You'll be able to see your test
renderings sooner and will waste less time on stuff that don't work.
Try to make your objects 500 units or larger. Imagine has a bit of a problem
with real small objects.
Lighting is the biggest problem Imagine has. A few tips are:
Indoor scenes should be lit with diminishing lights.  If you don't use
diminsihing lights the scene won't look right. Lights can be set at up to
32000 on red, green, and blue. You won't use values that high but you will
often have to get up into the over 255 range. When you change the size of an
object you will also change the way it's lit. For example: You build a
kitchen and manage to get all the lighting set up so it looks OK. You realize
you have to enlarge the object to make it fit the rest of the house. You
kitchen would now be too dark because the light has to travel further to
illuminate any surfaces. You'll have to do a lot of test renderings to get
decent results.

Problems with full traces:
If you lose parts of objects in full trace mode you should go into the Action
Editor and all a size bar to the globals. Set the xyz sizes at 0. This will
auto-size the Imagine universe for each frame it renders.

If your scanline renderings come out OK but your images are really dark in
full trace you probably have your lights inside objects. (lightbulbs, candle
flames, ect) The problem is that the surface of your lightbulb is not letting
the light through unless you set the transparency to maximum which doesn't
look real. The best solution I've found it to move the light outside of the
object and make sure the object's not too close to a wall so you can't tell
exactly where the light comes from.

Hope this advice helps you get a little better results. If you don't have it
already you should also get 'Understanding Imagine 2.0' by Steve Worley. It's
an excellent reference book that has a lot of information that's not in the
Imagine manual.


Organization: Freshman, CIT general, Carnegie Mellon, Pittsburgh, PA