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816 Chapter 13: reactor
Timing
At the b ottom of the window, profiling and t iming
information is shown :
The information presented is:
•Thecurrenttime step (simulation step) (page
2–709) used for the simulation. This value is
initially taken from the Preview & Animation
rollout (page 2–806) but can also be changed by
using t he Performance menu (page 2–817).
•Thenumberofsubsteps (page 2–709) used for
the simulation. Again, this value is initially
taken from the Preview & Anima tion rollout
(page 2–806) but can a ls o b e changed by using
the Performance menu (page 2–817).
• The current simulation time; that is, the time
that the current image in the preview represents
in the final animation.
Duri ng the preview, reactor tries to run the
simulation in real time. In other words, if a
sim ulation step of one second takes only 0.7
second of CPU to simulate, reactor "waits" 0.3
second before simulating the next s tep. That way,
the animation is presented in the window at the
same speed as the final animation in 3ds Max.
However, for complex scenes or slow CPUs,
simulat ing a particular period of ti m e can t ake
actually more CPU time than the specified period.
For example, a simulation step of one second
might actually take two seconds to calculate. In
that case, it is not possible to present t he animation
in real time, and the animation is therefore
presented during the preview at a slower speed
that the final animation will have once it has been
created. When this happens, the previe w reports it
by appending an asterisk (*) to the current time:
Simulation menu
Play/Pause ( P )—Starts and p auses the simulation.
If the simulation is paused, the display remains
active and you can still pan, rotate, and zoom the
camera, but the physics world remains still.
Reset ( R )—Resets the s imulation, returning
objects to their init ial positions.
Display m enu
Impor tant: When About rollout > Choose Solver is set
to Havok 3, only Camera Settings is available from this
menu.
Camera S ettings—
Opens a dialog that allows you
to specify the near and far clipping planes for
the camera, and to change the camera’s field of
view (F.O.V.). The clipping planes can also be set
externally from the reactor utility Displa y rollout.
Faces—When on, the faces (and not the edges) of
the d isplay bodies are rendered.
Wireframe—When on, the edges (and not the
faces)ofthedisplaybodiesarerendered.
Sim Edges—When on, the edges of the physically
simulated geometry (the simulation geometry
for each body) are rendere d in the preview
window.Thisisusefulforseeingwhat’sphysically
happening in a simulation.
Gri d—When on, three 2D grids are displayed in
the XY, Y Z and ZX planes.
Origin—Whenon,theX(inred),Y(ingreen)and
Z (in blue) axis are displayed at the origin (0,0,0).
Flashlight On/Of f—When on, a flashlight located
behind the camera lights the scene. When off,
lights defined on the Display rollout of the utility
are used. If no lights are defined, the preview uses
a sing le fixed light.