|Maya: Use nCloth to animate scroll unrolling|
nCloth is an incredibly powerful dynamic engine built into Maya. Simulating cloth and fabric is really easy, and in this tutorial I will show you how to use it to create a scroll unrolling. The first part is creating a profile of the scroll in 2D vector program. I’ll be using Illustrator.
1. Select the spiral tool, use the following settings: Radius: 400px, Decay: 90%, Segments:20
2. Object -> Path -> Simplify… Check Straight Lines
3. Save as legacy Illustrator file, I chose version 3 because anything higher wasn’t importing into Maya
1. Open new scene, File -> Import, Select Adobe Illustrator as file type
2. Using the CV Curve tool, draw a straight line. This will serve as the path curve. Now select the spiral and then the line. Surface -> Extrude.
3. In order to use this with nCloth, we need to convert this to a polygon object.
4. Modify -> Convert -> NURBS to Polygons options. Refer to figure 3 for all the settings. These are the only two settings that you need to change, Type: Quads, Tessellation method: General
5. We need to add some more polygons in the U direction for the scroll. Edit Mesh -> Add Divisions, Division in U: 2, Divisions in V: 1. Do this two time.
6. Now create a cube, and shape it into a pole that the scroll will constrain to. Otherwise the scroll will simply free fall due to gravity.
7. Now smooth the polygon scroll: Mesh -> Smooth. Select all the edges on left and right side of the scroll, extrude. Use your discretion when extruding, the extruded faces will be used to hold the hair system we’re adding in later. In polyExtrudeEdge1 panel, under Poly Extrude Edge History, change Z value under Local Translate to -0.099.
8. Make sure the polygon model has a UV layout. This is important since the hair system is dependent on UVs. Use the UV texture Editor to layout the UVs for the scroll.
9. Switch to nCloth mode, select your scroll: nCloth -> Create nCloth.
10. Switch to component mode and select all the points on the top border. Now select the pole: nConstraint -> Transform. The scroll is now constrained to the pole.
11. Select the extruded faces we made earlier. It’s time to make some hair. Switch to Dynamics mode: Hair -> Create Hair options. Just ensure At selected points/faces is selected. Now you got fringes for your scroll. You might need to adjust the hair settings in the hairSystemShape attribute, such clump and hair shape.
12. You will need to tweak the nCloth settings in order to get the right look and feel for the animation. I used the following settings:
Collide and Self Collide checked
Collision Flag: Edge, Self Collision Flag: VertexEdge
Self Collide Width Scale: 2
Stretch Resistance: 600
Compression Resistance: 800
Bend Resistance: 0.5
Max Iterations: 500
Max Self Collide Iterations: 10
Self Trapped Check
Everything else is default
Gravity and Wind
Air Density: 1
Wind Speed: 0
Wind Direction: 0,0,0
Space Scale: 0.1
13. It’s time to see the animation. Make sure the timeline is long enough. I usually set mine to 1000 frames. Select Window -> Playblast. This shows you an accurate version of the dynamic simulation.
Take a look at the final animation here.
Thanks for reading.