Stefan, who is my good friend and long term partner, not partner like lovers, but like New York city cop type partner, solving mystery's and busting crime, was asking about using the maya paint effects. We wanted to know how to randomly scatter grass on a mesh, rather then painting it individually with brush strokes. So here we go, weee!
1: Assuming you have a mesh setup and ready to go, make sure you are in 'rendering' sets or hit 'F6'. Then goto 'Paint Effects' in the menu bar, and with your mesh selected hit 'Make Paintable'.
This will allow you to paint on your mesh now with paint effects, constraining your brush to that mesh so you don't go randomly all over the place like some kind of clown.
2: Select 'Get brush' in the 'Paint Effects' menu, this will allow you to choose from many different types of brushes, i suggest the brick one because it looks like err... lets go with the grass, found under grasses.
3: Once you have selected your brush, select your mesh. In the paint effects menu go to 'Auto Paint' -> 'Paint Random' and hit the option box. This will pop up an option box like this:
The main options you will need to look at are 'Spans U:' and 'Spans V'. This is how many strokes you along U and V. The more you have the more grass you will have. I hit it up to 100 and it crashed Maya. 30 seems to work well, for a nice lush grass.
4: Hit 'Apply'. Maya will think for a bit, then your grass will be applied. You may find your grass coming out looking like this:
The grass is just to small to notice at the moment. To fix this, we just need to up the 'Global Scale' in the 'Attributes editor'. You should just be able to go straight to your attributes editor now and change the global scale, should be under 'GrassClump100' (will be the tap next to 'strokeShape'. The number will depend on how many U and V spans you set, as it creates a random brush across your mesh to these spans. If you dont have any grass selected you can first open up your outliner and select 'Stroke 1', then open your Attributes editor, select 'GrassClump100' and find 'Global Scale'
Now you have some nice looking grass, randomly scattered across your mesh. saves time, and money, and time.
Also note, that where you change your 'Global Scale' options in your Attributes Editor, there are many other options you can play with to make your paint effects look the way you want them. For more info on this, check out the Maya help files, or Google search.
Hot Tup: I got none, eat it.