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Flex Modifier 683
Fl ex M odi f ier
Select a Mesh , Patch, or NURBS object. > Modify panel >
Modifier List > Objec t-Space Modifiers > Flex
Select a Mesh, Patch, or NURBS object. > M odifiers menu
> Animation Modifiers > Flex Modifier
Flexcausesthetonguetowagastheheadrotates.
The Flex modifier simulates soft-body dy namics
using virtual springs between an object’s vertices.
You c an set the springs’ stiffness, or how actively
they keep vertices from coming close to each other,
as well as stretch, or how far apar t they can move.
At a more advanced level, you can also control the
sway, or how much the spring angle can change.
At its simplest, this system causes vertices to lag
behind an object as it moves.
FlexworkswithNURBS,patches,meshes,shapes,
FFD space war p s, and any plug-in-based object
types that can be deformed. You can combine Flex
with space warps such as Gravity, Wind, Motor,
Push, and PBomb to add realistic physically based
animation to an object. In addition, you can
apply deflectors to soft-body objects to simulate
collision.
Note: The Flex modifier is aware of
vertex/control-point motion in any animated
modifier that deforms points below Flex in the
modifier stack, such as the
Morpher modifier (page
1–721)
. Use this to simulate soft body motion on a
morphed or otherwise deform-animated object.
Tip: After applying the Flex modifier to an object
or sub-object selection, choose the F lex modifier’s
Center sub-object and use Move to change where
the flex effect is centered.
Tip: Using Flex’s advanced capabilities can
significantly i mpede real-time playback. In such
cases, use the
Point Cache modifier (page 1–750)
to record the vertex animation to disk, and then
play it back using the cache.
The antennae, with the Flex modifier ap p lied, move around
like springs reacting to the motion of the character’s head.
Sur fa ces I nfluenced by the Flex Modifier
• On a mesh surface, the Flex modifier influences
every vertex.
• On a p atch surface, the Flex modifier influences
both control points and tangent handles.
Tangent handles are u n locked and moved
independently by the Flex mod ifier.