Gnomon DVD: Paint Effects 101
Ethan Summers introduces us to paint effects, which he refers to as part paint program, part particles system, part L-system (branching), part post-effect. It’s intuitive, yet there is a huge number of attributes that we can tweak and could get technical. We could pretty much get a lot out of paint effects in Maya: plants, food, fire, cities.
The 2D paint effects allows us to paint like in real life. There is not much undo, lots of different brushes. Nice!
3D paint effects has things like length and tube attributes, giving it volumes. We could convert the strokes into polygons, then render with mental ray. A thing to take note would be to have quad on during conversion, so our renders would look better.
3D brush modes like mesh deals with things like displacement. It gives you haflway between paint effects and polygons. Thin line brush suits the painting of hair.
We can adjust the display settings for faster performance, pen pressure, use different brush modes (paint, smear, blur, erase) etc. Use hokey ‘8’ to go to paint effects view.
In attributes, the forward twist checkbox makes the strokes function like sprites. Texture attributes override shading attributes. There are some fake shadows that we can cast, like the 3D cast that is extremely cheap, but otherwise, enabling shadows will allow lights to cast shadows on it.
For glow effects, Ethan recommends using shaderGlow which is more accurate.
Much of the technical aspects of paint effects lies in tubes attributes. We can adjust the look of the most minute detail within here. A tip about leaves is to us leaf forward twist so we populate leaves for the shot instead of getting high poly count.
Flow animation is an exciting attribute which allows us to animate the growth of a paint effect stroke. Start time and end time will affect if the stroke dies off or remains throughout the timeline. Time clip makes the segments grow out simultaneously. Using flow animation, we can make polygons that emits particles along the path of its growth, a rather useful application.
To paint on an object, we need to go under paint effects> make paintable. B key changes the brush size, while M key changes the offset distance. Under brush animation, we could use loop brush animation when we apply something like turbulence to a tree and want to render an instance of that so that it can be applied to a card in the distance with many trees, creating the illusion of swaying trees. Make brush spring simulates something like hair, which follows through an animation. Control curves allows us to animate certain portions of the stroke, like a bird landing on a branch. Pressure mappings can connect a curve to different attributes of a stroke, like controlling size of individual trees along a path.
I feel the possibilities are endless in paint effects. Though it might be a costlier way to do a shot, I feel like it’s amazing if directors get to play with this.