rusty-telemetry/src/parser_ksudp.rs
Jan-Peter v. Hunnius d86a87ab7d refactor: fix all compiler + clippy warnings
- analysis.rs: use .clamp() instead of .max().min(), saturating_sub,
  inline corner_start into corner_start_s (dead assignment removed)
- binary_utils.rs, parser_pcars.rs: use std::array::from_fn for array reads
- recording.rs: std::io::Error::other() instead of Error::new(ErrorKind::Other),
  #[allow(dead_code)] on diagnostic methods (len, total_pushed, dropped_count, ring_stats)
- track_model.rs: prefix unused path vars with _, #[allow(dead_code)] on exists()
- parser_ksudp.rs: fix doc list item indentation
- session.rs: std::mem::take instead of mem::replace(..., Default::default())

cargo build: 0 warnings, clippy: 0 warnings, 33 tests pass
2026-06-25 11:40:38 +02:00

284 lines
10 KiB
Rust

// rusty-telemetry — Sim racing telemetry analysis platform
// Copyright (C) 2026 Jan-Peter v. Hunnius
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>.
//! Binary parser for KSUDP RTCarInfo packets (Assetto Corsa port 9996).
//!
//! After the 3-phase handshake, AC sends continuous RTCarInfo structs at ~20 Hz.
//! This parser converts the raw binary data into a `TelemetryFrame`.
//!
//! IMPORTANT: The AC RTCarInfo C struct uses **natural alignment** (not packed).
//! This means padding bytes exist:
//!
//! - 3 bytes after `char identifier` (offset 0) before `int size` (offset 4)
//! - 2 bytes after the 6 bools (offsets 20-25) before the next float (offset 28)
//!
//! Total struct size: 328 bytes (not 323).
use crate::binary_utils::{read_bool, read_f32, read_f32_4, read_i32};
use crate::telemetry_frame::{FeedSource, TelemetryFrame};
/// Minimum expected packet size for a naturally-aligned RTCarInfo struct.
/// The `size` field in the packet itself reports the true struct size (328).
const MIN_PACKET_SIZE: usize = 328;
/// Parse error type for KSUDP packets.
#[derive(Debug)]
pub enum KsudpParseError {
/// Packet too short to contain a valid RTCarInfo.
TooShort { actual: usize, expected: usize },
/// Invalid identifier byte (expected 0x61 = 'a').
InvalidIdentifier { got: u8 },
}
impl std::fmt::Display for KsudpParseError {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
match self {
KsudpParseError::TooShort { actual, expected } => {
write!(f, "packet too short: {} bytes (expected >= {})", actual, expected)
}
KsudpParseError::InvalidIdentifier { got } => {
write!(f, "invalid identifier: 0x{:02x} (expected 0x61 = 'a')", got)
}
}
}
}
impl std::error::Error for KsudpParseError {}
/// Parse a raw KSUDP RTCarInfo packet into a `TelemetryFrame`.
///
/// Field offsets follow the naturally-aligned C struct layout:
/// - offset 0: char identifier
/// - offset 4: int size (3 bytes padding after char)
/// - offset 8: float speedKmh
/// - offset 12: float speedMph
/// - offset 16: float speedMs
/// - offset 20: bool isAbsEnabled .. isEngineLimiterOn (6 bools at 20-25)
/// - offset 28: float accG_vertical (2 bytes padding after bools)
/// - offset 32: float accG_horizontal
/// - offset 36: float accG_frontal
/// - offset 40: int lapTime
/// - offset 44: int lastLap
/// - offset 48: int bestLap
/// - offset 52: int lapCount
/// - offset 56: float gas
/// - offset 60: float brake
/// - offset 64: float fuel (not clutch — KSUDP has no clutch input)
/// - offset 68: float engineRPM
/// - offset 72: float steer
/// - offset 76: int gear
/// - offset 80: float cgHeight
/// - offset 84: float[4] wheelAngularSpeed
/// - offset 100: float[4] slipAngle
/// - offset 116: float[4] slipAngleContactPatch
/// - offset 132: float[4] slipRatio
/// - offset 148: float[4] tyreSlip
/// - offset 164: float[4] ndSlip
/// - offset 180: float[4] wheelLoad
/// - offset 196: float[4] wheelDy
/// - offset 212: float[4] wheelMz
/// - offset 228: float[4] tyreDirtyLevel
/// - offset 244: float[4] camberRAD
/// - offset 260: float[4] tyreRadius
/// - offset 276: float[4] tyreLoadedRadius
/// - offset 292: float[4] suspensionHeight
/// - offset 308: float carPositionNormalized
/// - offset 312: float carSlope
/// - offset 316: float worldX
/// - offset 320: float worldY
/// - offset 324: float worldZ
///
/// # Errors
/// Returns `KsudpParseError` if the packet is too short or has an invalid identifier.
pub fn parse_rt_car_info(data: &[u8]) -> Result<TelemetryFrame, KsudpParseError> {
if data.len() < MIN_PACKET_SIZE {
return Err(KsudpParseError::TooShort {
actual: data.len(),
expected: MIN_PACKET_SIZE,
});
}
let identifier = data[0];
if identifier != b'a' {
return Err(KsudpParseError::InvalidIdentifier { got: identifier });
}
let reported_size = read_i32(data, 4) as usize;
if data.len() < reported_size && reported_size > 0 {
eprintln!(
"[WARN] KSUDP: reported struct size {} but packet is {} bytes",
reported_size,
data.len()
);
}
let frame = TelemetryFrame {
source: FeedSource::Ksudp,
raw_size: data.len(),
speed_kmh: read_f32(data, 8),
speed_mph: read_f32(data, 12),
speed_ms: read_f32(data, 16),
is_abs_enabled: read_bool(data, 20),
is_abs_in_action: read_bool(data, 21),
is_tc_in_action: read_bool(data, 22),
is_tc_enabled: read_bool(data, 23),
is_in_pit: read_bool(data, 24),
is_engine_limiter_on: read_bool(data, 25),
acc_g_vertical: read_f32(data, 28),
acc_g_horizontal: read_f32(data, 32),
acc_g_frontal: read_f32(data, 36),
lap_time_ms: read_i32(data, 40),
last_lap_ms: read_i32(data, 44),
best_lap_ms: read_i32(data, 48),
lap_count: read_i32(data, 52),
throttle: read_f32(data, 56),
brake: read_f32(data, 60),
clutch: 0.0, // offset 64 is fuel level (0.0-1.0), not clutch; KSUDP has no clutch input
engine_rpm: read_f32(data, 68),
steer: read_f32(data, 72),
gear: read_i32(data, 76),
cg_height: read_f32(data, 80),
wheel_angular_speed: read_f32_4(data, 84),
slip_angle: read_f32_4(data, 100),
slip_angle_contact_patch: read_f32_4(data, 116),
slip_ratio: read_f32_4(data, 132),
tyre_slip: read_f32_4(data, 148),
nd_slip: read_f32_4(data, 164),
wheel_load: read_f32_4(data, 180),
wheel_dy: read_f32_4(data, 196),
wheel_mz: read_f32_4(data, 212),
tyre_dirty_level: read_f32_4(data, 228),
camber_rad: read_f32_4(data, 244),
tyre_radius: read_f32_4(data, 260),
tyre_loaded_radius: read_f32_4(data, 276),
suspension_height: read_f32_4(data, 292),
car_position_normalized: read_f32(data, 308),
car_slope: read_f32(data, 312),
world_x: read_f32(data, 316),
world_y: read_f32(data, 320),
world_z: read_f32(data, 324),
spline_position: read_f32(data, 308),
..Default::default()
};
Ok(frame)
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_parse_minimal_valid_packet() {
let mut packet = vec![0u8; MIN_PACKET_SIZE];
packet[0] = b'a';
packet[4..8].copy_from_slice(&(MIN_PACKET_SIZE as i32).to_le_bytes());
packet[8..12].copy_from_slice(&123.4f32.to_le_bytes());
packet[76..80].copy_from_slice(&3i32.to_le_bytes());
packet[68..72].copy_from_slice(&7500.0f32.to_le_bytes());
packet[40..44].copy_from_slice(&78123i32.to_le_bytes());
let frame = parse_rt_car_info(&packet).unwrap();
assert_eq!(frame.source, FeedSource::Ksudp);
assert!((frame.speed_kmh - 123.4).abs() < 0.01);
assert_eq!(frame.gear, 3);
assert!((frame.engine_rpm - 7500.0).abs() < 0.01);
assert_eq!(frame.lap_time_ms, 78123);
}
#[test]
fn test_too_short() {
let packet = vec![b'a', 0, 0, 0, 0];
let result = parse_rt_car_info(&packet);
assert!(result.is_err());
if let Err(KsudpParseError::TooShort { actual, .. }) = result {
assert_eq!(actual, 5);
} else {
panic!("Expected TooShort error");
}
}
#[test]
fn test_invalid_identifier() {
let mut packet = vec![0u8; MIN_PACKET_SIZE];
packet[0] = b'x';
let result = parse_rt_car_info(&packet);
assert!(result.is_err());
if let Err(KsudpParseError::InvalidIdentifier { got }) = result {
assert_eq!(got, b'x');
} else {
panic!("Expected InvalidIdentifier error");
}
}
#[test]
fn test_boolean_flags() {
let mut packet = vec![0u8; MIN_PACKET_SIZE];
packet[0] = b'a';
packet[20] = 1;
packet[21] = 0;
packet[22] = 1;
packet[23] = 1;
packet[24] = 0;
packet[25] = 1;
let frame = parse_rt_car_info(&packet).unwrap();
assert!(frame.is_abs_enabled);
assert!(!frame.is_abs_in_action);
assert!(frame.is_tc_in_action);
assert!(frame.is_tc_enabled);
assert!(!frame.is_in_pit);
assert!(frame.is_engine_limiter_on);
}
#[test]
fn test_per_wheel_arrays() {
let mut packet = vec![0u8; MIN_PACKET_SIZE];
packet[0] = b'a';
for i in 0..4 {
let val = (i as f32 + 1.0) * 0.1;
packet[132 + i * 4..132 + i * 4 + 4].copy_from_slice(&val.to_le_bytes());
}
let frame = parse_rt_car_info(&packet).unwrap();
assert!((frame.slip_ratio[0] - 0.1).abs() < 0.001);
assert!((frame.slip_ratio[1] - 0.2).abs() < 0.001);
assert!((frame.slip_ratio[2] - 0.3).abs() < 0.001);
assert!((frame.slip_ratio[3] - 0.4).abs() < 0.001);
}
#[test]
fn test_world_coordinates() {
let mut packet = vec![0u8; MIN_PACKET_SIZE];
packet[0] = b'a';
packet[316..320].copy_from_slice(&100.5f32.to_le_bytes());
packet[320..324].copy_from_slice(&2.3f32.to_le_bytes());
packet[324..328].copy_from_slice(&(-50.7f32).to_le_bytes());
let frame = parse_rt_car_info(&packet).unwrap();
assert!((frame.world_x - 100.5).abs() < 0.01);
assert!((frame.world_y - 2.3).abs() < 0.01);
assert!((frame.world_z - (-50.7)).abs() < 0.01);
}
}