Fix WPILib 2026 protocol compatibility #15
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Replace qMakePair<T1,T2>() calls with QPair<T1,T2>() constructor Qt 6 requires rvalue references for qMakePair arguments
This fixes crashes when using QDriverStation with WPILib 2026 simulation. Changes: - Fix joystick size calculation to not include length byte in the count - Fix button encoding to use variable-length bytes ((numButtons+7)/8) instead of always sending 2 bytes - Add WPILib HAL limits (12 axes, 32 buttons, 12 POVs) to prevent protocol errors with controllers that exceed these limits - Support up to 32 buttons (was limited to 16) The crash was caused by WPILib's DecodeUDP receiving incorrect packet sizes, leading to invalid memory access. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
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Summary
This PR fixes crashes when using QDriverStation with WPILib 2026 simulation.
Problem
When connecting QDriverStation to WPILib 2026's simulation, the robot code would crash with a SIGSEGV in
DecodeUDPdue to protocol encoding mismatches.Root Cause
Two issues in the joystick packet encoding:
Joystick size calculation bug:
get_joystick_size()was including the length byte itself in the count. WPILib expects the length byte to represent the size of data after the length byte.Button encoding bug: The code always sent 2 bytes for button data, but WPILib expects
(numButtons + 7) / 8bytes (variable length based on button count).Changes
get_joystick_size()to correctly calculate joystick data size (excluding length byte)get_button_bytes()helper function for proper button byte count calculationTesting
Tested with:
Robot simulation now runs stably without crashes when QDriverStation connects.
Test plan
🤖 Generated with Claude Code