fix(Joystick): fix 0-to-MAX trigger axis calibration and UI preview

[M4rkoHR]

• Lower movement delta thresholds during Joystick mode so half-axis (0-to-MAX) triggers auto-detect.
• Update _validateAndAdjustCalibrationValues to prevent resetting valid trigger spans that do not cross 0.
• Stretch half-axis values in _adjustChannelRawValue to display full -MAX to +MAX travel in the QML Attitude Controls preview.

Description

When calibrating a gamepad trigger or other half-axis control (which physically outputs 0 to 32767 rather than -32768 to 32767) mapped to a primary attitude control like Throttle, the calibration workflow previously suffered from three key issues:

1. Auto-Detect Failure: Triggers resting at 0 or 16383 failed to trigger automatic stick movement detection during _inputStickDetect and _inputStickMin because the logic required crossing a hardcoded negative center threshold (0). Users were forced to manually click the "Next" button to proceed.
2. Validation Reset: At the end of calibration, _validateAndAdjustCalibrationValues() reset any non-extension channel whose channelMin did not cross a negative lower bound (_calValidMinValue). This wiped valid trigger calibrations back to default -32768 bounds.
3. UI Preview Clipping: Because the QML Attitude Controls preview expects a normalized -32768 to 32767 range, applying non-negative trigger inputs against default bounds caused the preview dot to sit at the middle (0) at rest and only move through the upper half of the display.

Changes Made:

• _inputStickDetect & _inputStickMin: Lowered the movement delta requirement in Joystick mode to 8000 and updated the _inputStickMin check to compare movement relative to the captured center value rather than hardcoded 0.
• _validateAndAdjustCalibrationValues: Added a validSpan check (channelMax - channelMin > 10000) so valid half-axis calibrations are retained rather than reset to defaults, and automatically sets channelTrim to the true midpoint when a trigger edge-resting trim is detected.
• _adjustChannelRawValue: Added linear range normalization in Joystick mode to scale physical 0 -> 32767 inputs across the full -32768 -> 32767 range for proper QML Attitude Controls preview rendering.

Type of Change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update
• Refactoring (no functional changes)
• CI/Build changes
• Other

Testing

• Tested locally
• Added/updated unit tests
• Tested with simulator (SITL)
• Tested with hardware

Platforms Tested

• Linux
• Windows
• macOS
• Android
• iOS

Flight Stacks Tested

• PX4
• ArduPilot

Screenshots

Throttle at minimum (channel 5):

Throttle at maximum:

Checklist

• I have read the Contribution Guidelines
• I have read the Code of Conduct
• My code follows the project's coding standards
• I have added tests that prove my fix/feature works
• New and existing unit tests pass locally

Related Issues

#11017

By submitting this pull request, I confirm that my contribution is made under the terms of the project's dual license (Apache 2.0 and GPL v3).

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[codecov]

Codecov Report

❌ Patch coverage is 3.33333% with 58 lines in your changes missing coverage. Please review.
✅ Project coverage is 34.52%. Comparing base (f29efd3) to head (f31d2da).
⚠️ Report is 354 commits behind head on master.

Files with missing lines	Patch %	Lines
...VehicleSetup/RemoteControlCalibrationController.cc	3.33%	56 Missing and 2 partials ⚠️

❌ Your patch check has failed because the patch coverage (3.33%) is below the target coverage (30.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #15032      +/-   ##
==========================================
+ Coverage   25.47%   34.52%   +9.05%     
==========================================
  Files         769      945     +176     
  Lines       65912    85676   +19764     
  Branches    30495    39492    +8997     
==========================================
+ Hits        16788    29583   +12795     
+ Misses      37285    36440     -845     
- Partials    11839    19653    +7814     

Flag	Coverage Δ
unittests	34.52% <3.33%> (+9.05%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...VehicleSetup/RemoteControlCalibrationController.cc	31.80% <3.33%> (+31.80%)	⬆️

... and 662 files with indirect coverage changes

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[github-actions]

Build Results

Platform Status

Platform	Status	Details
Linux	Passed	View
Windows	Passed	View
MacOS	Passed	View
Android	Passed	View

All builds passed.

Pre-commit

Check	Status	Details
pre-commit	Failed (non-blocking)	View

Pre-commit hooks: 2 passed, 76 failed, 7 skipped.

Test Results

linux-coverage-integration: 52 passed, 0 skipped
linux-coverage-unit: 185 passed, 0 skipped
linux-sanitizers-integration: 31 passed, 0 skipped
linux-sanitizers-unit: 185 passed, 0 skipped
Total: 453 passed, 0 skipped

Code Coverage

Coverage: 70.6%

No baseline available for comparison

Artifact Sizes

Artifact	Size
QGroundControl	253.11 MB
QGroundControl-aarch64	177.29 MB
QGroundControl-installer-AMD64	128.44 MB
QGroundControl-installer-AMD64-ARM64	70.81 MB
QGroundControl-installer-ARM64	99.55 MB
QGroundControl-linux	84.76 MB
QGroundControl-mac	84.76 MB
QGroundControl-x86_64	189.57 MB
No baseline available for comparison

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_{Updated: 2026-09-03 09:18:52 UTC • Commit: f31d2da • Triggered by: Linux}