81 lines
4.1 KiB
Text
81 lines
4.1 KiB
Text
|
Lead Computer Configuration:
|
||
|
|
|
||
|
|
The following properties will need to be set to configure the lead computer for your aircraft.
|
||
|
|
|
||
|
|
These are set in the aircraft's *set.xml file in the section where you are setting initialization values
|
||
|
|
for various properties. This MUST happen before the nasal section in the *set.xml file.
|
||
|
|
|
||
|
|
The following five values can be found in the submodels.xml configuration file where the guns
|
||
|
|
ballistics are configured.
|
||
|
|
|
||
|
|
/controls/armament/gunsight/z-gunOffsetFeet = Gun position on z axis relative to the sight line in feet.
|
||
|
|
|
||
|
|
Will = <z-offset>offset value</z-offset> + distance from aircraft center line to sight line height in feet.
|
||
|
|
|
||
|
|
/controls/armament/gunsight/y-gunOffsetFeet = Gun position on y axis relative to the sight line in feet.
|
||
|
|
|
||
|
|
Will = <y-offset>abs value</y-offset> if the guns are equally distributed about the aircraft center line
|
||
|
|
set this to 0. If this value in non-zero this is in feet.
|
||
|
|
|
||
|
|
/controls/armament/gunsight/gunElevationDegrees = <pitch-offset>gun pitch setting</pitch-offset> in degrees.
|
||
|
|
|
||
|
|
/controls/armament/gunsight/ballisticCoefficienct = <eda>xxxxx</eda>
|
||
|
|
|
||
|
|
/controls/armament/gunsight/muzzleVelocity = <speed>xxxxx</speed> = In feet per second
|
||
|
|
|
||
|
|
Additional parameters need to be set that are not in the submodels.xml file.
|
||
|
|
|
||
|
|
/controls/armament/gunsight/gunHarminizationRangeFeet = Range where the sight and the bullet
|
||
|
|
path cross is straight and level flight in feet.
|
||
|
|
|
||
|
|
/controls/armament/gunsight/timeStep = The computer cycle time in seconds.
|
||
|
|
|
||
|
|
This will typically be values between 0.5 and 0.05. These correspond to
|
||
|
|
lead computer update frequencies of 2 to 20 times per second. Use a slower update
|
||
|
|
rate for older purely mechanical gun sights and faster rates for newer fully
|
||
|
|
digital gun sights. Slower rates will tend to make the gun sight lag.
|
||
|
|
|
||
|
|
/controls/armament/gunsight/dampingFactor = The computer damping factor adjustment.
|
||
|
|
|
||
|
|
The optimum dampingFactor is 1.0. Lower values will make the reticle less stable and
|
||
|
|
prone to over shoot and jitter. However using lower values may result in a more
|
||
|
|
accurate simulation of older mechanical gun sights which were under damped. Modern
|
||
|
|
gun sights will be well damped and for those this should be set to 1.0. This value is
|
||
|
|
capped by the lead computer and values above 1.0 will result in 1.0 being used and
|
||
|
|
values below 0.3 will result in 0.3 being used.
|
||
|
|
|
||
|
|
/controls/armament/gunsight/MaxAzimuth and /controls/armament/gunsight/MaxElevation = The
|
||
|
|
maximum deflection of the sight reticle in mils. Used to limit the movement of the reticle
|
||
|
|
to the mechanical limits of sight being simulated.
|
||
|
|
|
||
|
|
Lead Computer Input Values:
|
||
|
|
|
||
|
|
/controls/armament/gunsight/range = The range to the target in feet.
|
||
|
|
|
||
|
|
With radar ranging this value will be constantly changing. Internally the lead computer
|
||
|
|
also uses this data to calculate the rate at which the range changes (IE. how fast
|
||
|
|
the target is being closed in on).
|
||
|
|
|
||
|
|
/controls/armament/gunsight/computer-on = 0 to turn the lead computer off and 1 to start the
|
||
|
|
lead computer. Cycling power will reinitialize the lead computer.
|
||
|
|
|
||
|
|
Lead Computer Output:
|
||
|
|
|
||
|
|
/controls/armament/gunsight/azimuth and /controls/armament/gunsight/elevation = Deflection
|
||
|
|
needed to hit the target in mils. 1 mil = 1 foot at a 1000 foot range. These values are
|
||
|
|
used to drive the sight reticle animation. This is usually done by applying these to a
|
||
|
|
factor that is then using the resulting product to move the reticle in the animation code.
|
||
|
|
|
||
|
|
Including the Lead Computer in the Aircraft's Set File:
|
||
|
|
|
||
|
|
For the lead computer to function it needs to be added to the aircrafts *set.xml file's nasal section.
|
||
|
|
|
||
|
|
This will look something like this.
|
||
|
|
|
||
|
|
<nasal>
|
||
|
|
<!-- your other nasal files -->
|
||
|
|
<!-- the following three lines must be exactly like this -->
|
||
|
|
<name of you gun sight>
|
||
|
|
<file>Aircraft/Instruments-3d/computing-gun-sights/Nasal/lead-computer.nas</file>
|
||
|
|
</name of your gun sight>
|
||
|
|
</nasal>
|