SOFTWARE: MAYA | MASH | ARNOLD
HOW TO USE SIMPLE MASH NETWORKS TO ACHIEVE TRULY RANDOMISED GEOMETRY DISTRIBUTION IN MAYA
Matt Burn explains:
“Randomisation is something that, as artists, the naked eye and human imagination simply cannot help but curate. We ‘free-willed’ beings cannot avoid making deliberate decisions while forming subconscious creative opinions during the artistic process. One could argue that we are ultimately incapable of generating something truly random, despite our best efforts. Luckily for us, computer software code isn’t limited by such instinctive deliberations.
In the context of CG, deliberate hand placement of environmental geometry inevitably leads to an unintentionally designed and considered aesthetic. We artists could sit there for hours trying to position objects by eye in a way that we think is random, but in truth it is not. No matter how hard we try, we’ll always struggle to emulate the truly random organic essence of mother nature. There is beauty to be found in chaos.
When lighting the Xgen grass for this 3D scene, it became apparent that something was missing. Our concept artist suggested adding some simple floral touches – bursts of colour to break up the green. However, after my initial placement efforts, ‘randomly’ positioning flowers by eye wasn’t working. It was just too… perfect.
Then I remembered MASH, a tool in Maya I had previously used for scattering trees around an environment. Using simple MASH node networks allowed me to achieve true randomisation of the geometry placement. By simply creating a few interlinked nodes and adjusting a few slider attributes, I landed somewhere I was much happier with, in an extremely short amount of time.
Of course, MASH is not just restricted to distributing flowers. Its toolset could be utilised to deliver a wide variety of outcomes – e.g. generating organic flocking bird movement, creating explosions, procedurally positioning roof tiles or even simulating dynamic flowing blood cells. MASH has so many interesting features and powerful possibilities for 3D artists that it’s impossible to list them all here – its extensive toolset is both useful and flexible.
Like everything in the world of CG, there are many, many ways to skin a cat. The end result could be reached a different way – combining nparticles with a geometry instancer and some simple per-particle expressions might also have been an option. Other techniques, software, plugins, MEL/ Python scripts are of course readily available.
We can’t possibly cover every setting, so let me keep this simple. MASH, like Maya, is huge. It goes way deeper than this walkthrough and the possibilities are literally endless. The real excitement starts when you begin experimenting with combinations of the available nodes yourself, but here are the basics of setting up a simple MASH network system to start with. Have fun with it!