I was just beginning to research how we could create the grass in our stargazing scene when I came across this method using paint effects. In this tutorial, Hermes demonstrates how you can simply paint clumps of grass with the stroke of your pen/mouse. These grass clumps can then easily be modified and animated by using the turbulence tab under the attributes. I will research more into how flexible this system is for creating our own style, particularly for adding elements that look like brush strokes, or on the opposite end of that, very flat and graphic.
In order to research more into how Paint Effects can be used I looked through chapter 10 of this book:
Mastering Autodesk Maya 2016
These were some of the questions which arose before or during my reading through the chapter.
Chapter 10 Paint Effects pg 419 – 471
What do I need to figure out from these chapters?
- How do I make my own custom shape to paint with?
- Can I shade these whatever way I want to? How can I make a custom grass shape and shade it the same colour? And then light it?
- Do they look good with light rendered with Maya software?
- How can I animate these with ‘turbulence’ to match the wind in the scene?
- What surface will I paint these on? Will the ground be visible?
- How can I shade and light the grass so that it only fluctuates between two colours when it blows in the wind. Dark grass that catches hard light. – light link only the grass, make the ground the same colour?
- Do you need to cache the wind/turbulence animation? Will the animation be retained in history?
These are some notes which I took while reading. There are still some areas which I haven’t covered yet e.g. Sorcha was telling me about painting along curves to create hair. At least I know that it’s possible.
Painting on 3D objects pg 425
- You can paint in any camera or through the paint effects window.
- You can create a bumpy/organic surface by lofting a surface between two dynamic hair curves (explained in a different chapter).
- Paint Effects can be used with pressure sensitivity on your stylus using the pressure mapping settings e.g. mapped to scale. I didn’t fully understand how to make this work at first so I searched online and found this video which helped:
Pluralsight Creative (2013) Top Tip: Using Pressure Sensitive Features Within Maya
- Both nurbs and polygon objects can be painted on.
- Make 3D objects “paintable”. Objects must be UV mapped in the 0 to 1 space. You can paint on a moving surface such as water. You can generate paint effects on a nurbs curve.
- A stroke node and a transform node is created when you paint. The brush node is also connected to the strokes and retains a construction history.
- Each stroke has its own brush node but you can edit brushes at the same time with brush sharing.
- You may need to make changes in the node editor e.g. to change the type of curve controlling the stroke.
- A different curve node is created depending on the type of surface which is painted on.
- Paint effects is a development of L-systems; mathematical algorithms used to simulate living organisms.
- Some brushes add shapes to the scene. Others work by affecting the appearance of geometry behind the brush. E.g. ‘erase’ paints black holes in the alpha channel.
- Mesh strokes don’t render in Mental Ray. However, strokes can be converted to polygons.
Rendering Paint Effects
- Light linking does not work with paint effects.
This article from Autodesk was helpful to load the Paint Effects shelf and add custom brushes to the shelf: Prepare to use Paint Effects.