Fun with Maya 4's Paint Effects
At first, Paint Effects seems like just a paint program with the option to paint trees and flowers, but it can also paint 3D objects onto other 3D objects. For example, you can paint a tree onto a terrain you've painted in a viewport, and the tree's componentsthe branches, twigs, and leaveswill actually exist in 3D space instead of looking like a flat, painted-on effect. You can also adjust and animate these elements to get a 3D environment with realistic light, movement, and shadows.
Paint Effects Overview
Paint Effects offers 3D artists a quick and easy way to add complex elements to a scene. Simple paint effects, such as Airbrush, Markers, and Swirl, are included in Maya's brush sets. You can see the potential of Paint Effects in more complex brushes, such as lightning and clouds, but it's the nature effectsflowers, shrubs, grasses, and treesthat really show off the possibilities of Paint Effects.
All this magic comes from tubes, which follow or continue the path of the stroke to simulate organic growth. For example, if you're painting a vine, tubes simulating leaves and tendrils can continue to "grow" from the main stalk. With the 3D effects that come from the brush's paint stroke, you can exhibit growth, dynamics, lighting, turbulence, and more. The paint stroke is attached to a NURBS curve, so it can be fully animated. You can edit the curve to grow, undulate, change shape, and move, and the brushes applied to the stroke will follow the curve. In the same manner, the brush type applied to a paint stroke can be changed so that a row of oaks, for example, can become a row of rose bushes.
With all these options, the palette of available 3D brushes is bogglingstars and galaxies, fire and lightning with inherent turbulence animation, trees and grasses that can be set to rustle in the wind, flowers and bushes that can grow as though in time-lapse photography, and much more. In contrast to the sometimes painstaking process of creating an animation, using Paint Effects is fast, fun, and easy.
Brushes and Strokes
You can find all the attributes for creating brush types in Maya in the Paint Effects Brush Settings dialog box (Hotbox | Paint Effects | Template Brush Settings). However, it's easier to create a brush by modifying one of the preset types. You can view the palette of preset brushes in Maya's Visor (hotkey: Shift+V; Window | General Editors | Visor on the menu; or Hotbox | Paint Effects | Get Brush).
A stroke is what's created when you paint with the Paint Effects tool, and it uses the settings of the brush type you've selected. The cursor becomes a pencil-like icon, and when you click and drag in the viewport, a paint stroke is created. This stroke is attached to a curve drawn over the surface of the object you're painting. You can offset the stroke from the surface curve for certain effects, such as fog patches that hover over the ground. After painting the stroke, you can select its curve to adjust the attached settings attached; to do that, select the stroke, and then choose Display | Show | Show Geometry | Stroke Path Curves. All the stroke and brush settings are in the Channel Box and Attribute Editor, as with other scene elements you create in Maya.
There are simple strokes and strokes with tubes (or "growth strokes"). Simple strokes are like paint strokesa single line created by brush motion. With growth strokes, as you drag the mouse to create the stroke, this action creates tubes that grow, separate, or expand to continue outward in several directions from the stroke. Tubes grow one "segment" for each step of the growth process; segments are straight, so increasing the Segments setting produces a smoother appearance. Another important setting is Tube Completion. When it's enabled, the tubes continue growing automatically for their full "life span" (defined by the number of segments). Usually, you leave this setting enabled.
Starting Paint Effects
Because using Paint Effects can require a lot of system resources, some people leave it disabled when they aren't planning to use it. To enable it, choose Window | Settings/Preferences | Preferences on the main menu; in the Preferences dialog box, select Modules in the Categories list box. Select the Load Paint Effects on Startup check box (if it's not already), and then close the Preferences dialog box and restart Maya. Paint Effects is then added to Maya's Rendering menu.
Choosing a Paint Mode
When you have designated a surface as paintable, you can then paint in one of the following three modes:
Model View mode: Painting in one of the normal 3D panels (in either Wireframe or Shaded mode). When painting in this mode, you see only a wireframe representation of your stroke and brush type.
Paint Scene mode: In this mode, when you switch into the Paint Effects panel, you'll see a shaded preview of your scene file. Paint Scene mode, shown in Figure 1, looks like the Perspective view, and can give you a good idea of what your paint strokes will look like by rendering them as you create them (although your display updates more slowly in this mode).
Figure 1 Painting flames in the Paint Scene mode.
Paint Canvas mode: Starts out as a white empty "canvas" when you switch into the Paint Effects panelgood for testing out brushes before trying them in your scene. Paint Canvas mode works as a sort of advanced 2D paint mode to create textures or paintings that can be saved as image files, and can store the depth and alpha channels of brushes.
To change the current panel to the Paint Effects panel, you press 8 or choose Hotbox | Panels | Panel | Paint Effects. You will be in Paint Scene or Paint Canvas mode (depending on the mode you were in last). To toggle between Paint Scene and Paint Canvas mode, right-click in the Paint Effects panel and choose Paint Scene or Paint Canvas.
Note that in tutorials, mouse button names are abbreviated as follows: LMB, left mouse button; MMB, middle mouse button; and RMB, right mouse button.