David Culp:

David Culp:

Silly me.  I was starting the timer at zero, so the first tracer didn't fly
until 0.25 seconds after pulling the trigger.  Now the timer starts at the
same value as "delay", so the first round comes out immediately.

Also, I've added an optional configuration attribute that allows you to change
the ballistics of the submodel.  This allows parachutes, or anything else
that has ballistics different from a bullet.  The attribute is called "eda",
which is the equivalent drag area.  Default value is 0.007, which gives the
same ballistics as the current tracers.  Increasing this value gives more
drag.  A value of 2.0 looks good for a parachute.

math stuff
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The deceleration of the ballictic object is now given by:

[ (rho) (Cd) ] / [ (1/2) (m) ] * A * (V * V)

where rho is sea-level air density, and Cd and m are fixed, bullet-like
values. So the calculation is:

0.0116918 * A * (V * V)

The value "A" is what I'm calling the "eda" (equivalent drag area).
########################################################################

A parachute model will have to be built so that the parachutist's feet
are in the forward x-direction.
Here is the submodel.xml config I use for "parachutes":

  <submodel>
    <name>flares</name>
    <model>Models/Geometry/flare.ac</model>
    <trigger>systems/submodels/submodel[0]/trigger</trigger>
    <speed>0.0</speed>
    <repeat>true</repeat>
    <delay>0.85</delay>
    <count>4</count>
    <x-offset>0.0</x-offset>
    <y-offset>0.0</y-offset>
    <z-offset>-4.0</z-offset>
    <yaw-offset>0.0</yaw-offset>
    <pitch-offset>0.0</pitch-offset>
    <eda>2.0</eda>
  </submodel>