Using HitchHiker – Building a Matte/Shadow material utility

Dec 21, 2010 by LoneRobot    2 Comments    Posted under: 3dsMax, DotNet, Imaging, Maxscript

This post is to show how you can use Hitchhiker to develop maxscript tools in super quick time. Any auto thumbnailer is going to have about a million uses in production in my humble opinion, as most of the development time on a utility is spend building the UI functionality. Whilst on the subject of dotnet controls, I would like to draw attention to another dotnet thumbnail control out there, written by TD Jason Labbe. It’s got a few things that Hitchhiker doesn’t have like multi select, so might be useful if Hitchhiker hasn’t quite got the functionality you need. Nice job Jason! You can read about it here

The Problem

On our last production, we had to consolidate a lot of complex sets into background renders as we were on tight deadlines. Often, the shot would need some form of contact shadow as well as masking so the obvious choice was to use the mental ray matte material. Depending on the type of shot, HD render times could be cut from 10 minutes per frame to around 45 seconds, with no perceptible loss of detail or quality.

The Solution

I wrote a utility that allowed the user to browse for the rendered backgrounds and quickly set the material up as a matte material, ready to be assigned to the background objects and rendered.

This utility is a good example of what you can use HitchHiker for. The browsing window allows you to pick the map that you want, and with the new cache mode property on the latest hitchhiker, is very fast. The greatest thing was that I wrote this entire script on my train ride home one day. This was exactly why I wrote HitchHiker, a plug and play solution to speed up my deployment of production scripts.

The material setup is simple,  matte/shadow.reflection (mi) shader is made with an Environment/Background Map (mi) shader. The texturemap is then set to screen and the blur taken down. You have to option to include the alpha so that you can use the render for composition. While the script itself is simple, it’s an example of how you can speed up a common bottleneck with very small programming outlay. Suffice to say, it checks that Mental Ray is the production renderer, as the materials are only compatible with that, but if you wanted to adjust it for use with an alternative material setup, it would be very easy. There is a method called :

CreateMatteShader <texmap> <slotnumber>

This could be changed to whatever you liked.

There is another assembly that is included with this script too, called ImageBot. It is an extended picturebox that allows you to zoom in on an area by dragging a marquee with the the right mouse button. This could also be used in other scripts, for example a rendered frame buffer.

How to use the script

Make a copy of your scene and render all static elements and save the rendered background file. Start MonsterMatte and use HitchHiker to navigate to the rendered file and select it. Press ‘Create Shader’. The matte material will be created and added to the designated material slot.

Apply the material to anything in the scene that isn’t animated and render – watch how fast it goes!

Installation

To install, just download the script below and copy the folders to the root of your max installation. You’ll see the macroscript listed under the ‘LoneRobot’ category and is called MonsterMatte. It’s not really a monster tool, but unfortunately when I was writing this article that monster mash song kept going round my head, damn pesky irritating brain.

Merry Xmas!

Got anything to say? Go ahead and leave a comment!