Monday 17 October 2022

Grass Waving Tutorial in Maya

Below a is a free tutorial on how to animate grass waving in Maya using the Paint Effects Tool, part of our series of tutorials on FX Animation

The tutorial shows how to use wind speed to simulate a light breeze in a grassy field.  

Also covered is how to export a geo cache and re-import the cache back into Maya. 

Paint Effects Tool
This tutorial shows how to create animation using the Paint Effects Tool in Maya, how to convert the Paint Effect into polygons and export a geo cache - so that you can then re-import the grass animation back into Maya.  The same tutorial can also be used to cover other plants such as trees, flowers and shrubs.

Animate Grass Waving in Maya
Watch the tutorial below


Lesson Plan
To see how to complete this tutorial step by step, follow the lesson plan below:

What You Will Learn
1. Use the Paint Effects tool in Maya to create the effect of grass 
2. Animate the grass so that it waves in the wind. 
3. Convert your paint effects into polygons. 
4. Light your set and create a movie file.

About Paint Effects
Note that the Paint Effects Tool can be used to create all sorts of things in Maya, from grass, trees, flowers, a blue neon sign or even a light bulb.  But Paint Effects has a big drawback: it is a heavy user of RAM, and will quickly slow down your workstation. So we will need to convert the paint effects into Polygons, export a geo cache, re-import the cache back into Maya, and then re-apply the textures. 

Work Method

Create Your Grass
1. File/Project window/new. Name yr project grassWave. Set to it.
2. Make sure you're in the Animation Mode from the drop-down window. Go to Windows/Content Browser
3. Select the PaintEffects tab and search for Paint Effect/Grasses/Grass Clump. Select the paint tool and paint a stripe of grass on your grid.  Note that one brush stroke = one object. 
4. In the grid, you will see the grass appear. You must turn on Strokes in your Maya Viewport. If nothing shows up, go into the grassClump1 tab in the Attribute Editor and increase Global Scale to make the grass bigger. Adjust density to get more or less grass.
5. Render a single frame using the Maya Software Render (Paint Effects will not render in Mental Ray).

Animate the Grass
6. To animate the grass, look inside the GrassClump1 tab . Find the Tubes tab, open it up, and find the Behaviour sub-tab. Click on the Turbulence sub-sub tab (simple, eh?) and under Turbulence Type select Grass Wind or Tree Wind. Set Turbulence for 2.0. Press play in your time line to see the result. Set Turbulence Speed to 0.6.
7. Under the Time Tab, press the button “Enable Timewarp”.
8. Adjust the settings until you like the result.  

Convert the Grass Effect to Polygons
9. When you are happy with the animation, convert it to polygons. Modify/Convert/Paint Effects to Polygons. You now have polygons in your shot. 

Export a Geo Cache
10. Select the polygons in the Outliner, and export the polygons as a geo cache (If you don’t select the polys correctly, this will not work) Make sure you are in the Animation Tab. Cache/Geometry/Export Cache 

Import Your Geo Cache back Into The Shot and Re-apply the Textures
11. Cache/Geometry/Import/cache/. Now you should have the geo cache in your shot.
12. Go to the Outliner and delete the original Paint Effect nodes – we don’t need them.
13. We now have grass waving in the wind with textures. 

Create a Shot Camera
14. Create/cameras camera. Name it shotCamera. Point it at your set and under panels select Look Through Selected. Adjust your camera view until you are happy with it. 

You're done!

FX Animation 
Increasingly FX animation is a growing part of the animation production pipeline.   FX animators tend not to occupy the same roles as keyframe animators; they tend to be specialists in FX, simulations and dynamics. 

Traditional keyframe animators don't need to become experts in dynamics and simulations, but they do need to know the basics.

Free FX tutorials
We have many FX tutorials available to our students at Escape Studios:

The Escape Studios Animation Blog offers a personal view on the art of animation and visual effects.  


1 comment: