[Q] CPE v2.2 "3D signature splat" (Public.Splat3D) – file format specification questions

[prom05]

Hello Command support team,

We are working with Command: Professional Edition and would like to use the
3D signature splat mechanics override introduced in v2.2. We hold
aspect-dependent RCS data for several aircraft (full azimuth x elevation grids
in dBsm, at several frequencies from about 1 to 10 GHz) and want to convert it
into splat files.

Our only reference so far is the blog post "When high fidelity counts: 3D
radar splat in Command PE" (https://command.matrixgames.com/?p=5546) and its
example file, Aircraft_1723_RadarAD.csv. Below is what we have inferred from
it. Could you confirm or correct it, and answer the questions that follow? If
a formal specification or manual section exists, that alone would probably
answer most of them.

If time is short, the most important for us are 5 (units), 8-10 (angle
conventions), 11 (interpolation) and 2 (signature type names).

Our current understanding:
- Files go in Resources\Overrides\Public.Splat3D\ and are named
Aircraft_<DBID>_<SignatureType>.csv, one per aircraft per signature type.
- Row 1 is an empty cell followed by the elevation samples, ascending,
-90 to 90 degrees.
- Every later row is an azimuth sample (ascending, -180 to 180 degrees, both
ends included) followed by one value per elevation.
- Samples may be irregularly spaced.
- "RadarAD" corresponds to the database's "Radar, A-D Band" signature.

B. Values
5. What unit are the values in? Command's database signatures are in dBsm,
but the example values (1 to 90) look implausible as dBsm (90 dBsm is
10^9 m2), so we want to be certain. What units apply to the visual and IR
signature types?
6. Are the values absolute signatures that replace the 6-side database
values, or modifiers applied to them?
7. Do external stores, signature modifiers and stealth flags still adjust a
splat signature? If so, how?

C. Angle conventions
8. Is azimuth 0 the nose? Is positive azimuth toward the right wing
(clockwise viewed from above) or toward the left?
9. Does positive elevation mean the observer is above the aircraft, seeing
its top surface?
10. Are the angles measured in the aircraft body frame, so that pitch and bank
change the aspect, or relative to heading and the local horizon only?

D. Sampling and interpolation
11. How are values between samples computed: linear, nearest neighbour or
something else? If linear, is it done in dB or in linear (m2) terms?
12. Must the table include -180/180 and -90/90? What happens for look angles
outside the table?

E. Frequency
15. With only two radar bands (A-D and E-M), is one table per band the
intended approach? Is there any provision for per-frequency or
per-polarization tables?
16. How does CPE decide which band's table applies to a given emitter?

F. AFSIM compatibility
17. The v2.2 release notes say CPE "can directly use AFSIM-format signature
tables". Does that mean only the CSV grid layout, or can CPE also read
AFSIM signature definitions or files directly (for example inline tables
with an explicit units token)? If the latter, which constructs are
supported?
18. Are signature states supported (for example weapon bay open or gear
down)?

[blu3s]

Hi!

For Professional support, please log in to your Matrix account through the Professional Portal and access the Help Desk from there.

Cheers!