You can have two kinds of emitter shapes: spherical and cylindrical. The shapes are generated from the explosion’s object icon, associated to the explosion cloud:
• The spherical shape (as shown below on the left) is for explosions that are fairly spherical in shape with a well-defined center.
• The cylindrical shape (as shown below on the right) is useful for explosions where there is an emission area and a directional particle vector, like a mushroom cloud or the blast from a rocket as it takes off.
You can translate, rotate, scale, and deform the emitter object to animate the shape of the explosion. The more the emitter is deformed along a direction (or set of directions), the more the emission and speed of structures is enhanced accordingly.
SOFTIMAGE|XSI v.6.01