From 764b5d938bfc67d7569f9ab513bfc7c91749ec80 Mon Sep 17 00:00:00 2001
From: enricobuehler <buehler@unom.io>
Date: Mon, 13 Jul 2026 22:24:03 +0200
Subject: [PATCH] fix(gamepad): resolve the menu diagonal tie-break
 horizontally on all clients (G25)

The gamepad-UI navigation resolvers disagreed on which way a perfect 45-degree
stick push (|x| == |y|) resolves: the SDL core picked horizontal (`ax >= ay`)
while Apple (`abs(x) > abs(y)`) and Android (`abs(Y) >= abs(X)`) picked vertical.
Align Apple (`>` -> `>=`) and Android (`>=` -> `>`) to the SDL core so an exact
diagonal moves focus the same way on every client (horizontal wins). This is
client-local menu navigation only and never reaches the wire. Completes the last
deferred G25 sub-part.

Verified: Apple `swift build` + full suite (124 pass); Android `:app:compileDebugKotlin`.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
---
 .../app/src/main/kotlin/io/unom/punktfunk/GamepadNav.kt      | 5 ++++-
 .../Sources/PunktfunkKit/Gamepad/GamepadMenuInput.swift      | 4 +++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/clients/android/app/src/main/kotlin/io/unom/punktfunk/GamepadNav.kt b/clients/android/app/src/main/kotlin/io/unom/punktfunk/GamepadNav.kt
index a9e8994b..dd98af48 100644
--- a/clients/android/app/src/main/kotlin/io/unom/punktfunk/GamepadNav.kt
+++ b/clients/android/app/src/main/kotlin/io/unom/punktfunk/GamepadNav.kt
@@ -241,7 +241,10 @@ private fun resolveDir(s: NavInputState): NavDir? {
     if (s.hatY >= 0.5f) return NavDir.DOWN
     if (s.hatX <= -0.5f) return NavDir.LEFT
     if (s.hatX >= 0.5f) return NavDir.RIGHT
-    return if (abs(s.stickY) >= abs(s.stickX)) {
+    // Horizontal wins an exact |x| == |y| diagonal tie (Y must be strictly greater to take the
+    // vertical branch), matching the SDL core and Apple nav so a perfect 45° push resolves the
+    // same on every client.
+    return if (abs(s.stickY) > abs(s.stickX)) {
         when {
             s.stickY <= -STICK_HIGH -> NavDir.UP
             s.stickY >= STICK_HIGH -> NavDir.DOWN
diff --git a/clients/apple/Sources/PunktfunkKit/Gamepad/GamepadMenuInput.swift b/clients/apple/Sources/PunktfunkKit/Gamepad/GamepadMenuInput.swift
index fb6d21e6..d162ebeb 100644
--- a/clients/apple/Sources/PunktfunkKit/Gamepad/GamepadMenuInput.swift
+++ b/clients/apple/Sources/PunktfunkKit/Gamepad/GamepadMenuInput.swift
@@ -140,7 +140,9 @@ public final class GamepadMenuInput {
         let stick = gamepad.leftThumbstick
         let x = stick.xAxis.value
         let y = stick.yAxis.value
-        if abs(x) > abs(y), abs(x) > deadzone {
+        // Horizontal wins an exact |x| == |y| diagonal tie (>=), matching the SDL core and Android
+        // nav so a perfect 45° push resolves to the same direction on every client.
+        if abs(x) >= abs(y), abs(x) > deadzone {
             return x > 0 ? .right : .left
         } else if abs(y) > deadzone {
             return y > 0 ? .up : .down