Land the press-rebound fix that raced the #1248 merge

Sources/KeyPathAppKit/UI/KeyboardStage/KeyboardStageInteraction.swift

@@ -157,12 +157,17 @@ extension KeyboardStageScene {
         copy.keys = keys.map { key in
             let pressLevel = interaction.pressed[key.keyCode] ?? 0
             let holdLevel = interaction.held[key.keyCode] ?? 0
-            let level = max(pressLevel, holdLevel)
-            guard abs(level) > 0.001 else { return key }
+            // Gate on the signed components, not their collapsed max: during
+            // the rebound a plain tap has pressLevel slightly negative and no
+            // hold level, and max(negative, 0) would discard exactly the
+            // frames the above-rest lift exists for.
+            guard abs(pressLevel) > 0.001 || abs(holdLevel) > 0.001 else {
+                return key
+            }
 
             var responsiveKey = key
             responsiveKey.opacity = max(responsiveKey.opacity, 0.98)
-            responsiveKey.interactionLevel = max(0, level)
+            responsiveKey.interactionLevel = max(0, max(pressLevel, holdLevel))
             let positivePress = max(0, pressLevel)
             let positiveHold = max(0, holdLevel)
             // The sub-linear press term makes the glow linger behind the

Sources/KeyPathAppKit/UI/KeyboardStage/KeyboardStageSceneBuilder.swift

@@ -124,11 +124,15 @@
                 dim(keys: &keys, except: [capsKeyID], opacity: 0.88)
                 keys[capsIndex].role = .escape
                 keys[capsIndex].pressure = 0.12
-                keys[capsIndex].translation.y = 0.12 * 0.023
                 keys[capsIndex].glow = 0.85
                 keys[capsIndex].opacity = 1
                 keys[capsIndex].scale = 0.78
-                keys[capsIndex].translation = KeyboardStagePoint(x: -0.48, y: -0.52)
+                // The authored transform pose owns the base translation; the
+                // physical press travel is applied on top of it.
+                keys[capsIndex].translation = KeyboardStagePoint(
+                    x: -0.48,
+                    y: -0.52 + 0.12 * 0.023
+                )
                 keys[capsIndex].legend = KeyboardStageLegend(
                     primary: "esc",
                     previous: "caps lock",
@@ -576,7 +580,7 @@
             ("control", "⌃", [KeyCode.leftControl, KeyCode.rightControl]),
             ("option", "⌥", [KeyCode.leftOption, KeyCode.rightOption]),
             ("shift", "⇧", [KeyCode.leftShift, KeyCode.rightShift]),
             ("command", "⌘", [KeyCode.leftCommand, KeyCode.rightCommand]),
         ]
 
         return descriptors.enumerated().compactMap { index, descriptor in
@@ -739,7 +743,7 @@
             25, // 9
             29, // 0
             27, // -
             24, // =
         ]
         static let tab: UInt16 = 48
         static let space: UInt16 = 49
@@ -762,7 +766,7 @@
             leftOption,
             rightOption,
             leftControl,
             rightControl,
         ]
     }
 }

Tests/KeyPathTests/KeyboardStage/KeyboardStageSceneTests.swift

@@ -63,7 +63,7 @@
             "hyper-token-control": [59, 62],
             "hyper-token-option": [58, 61],
             "hyper-token-shift": [56, 60],
             "hyper-token-command": [54, 55],
         ]
 
         for token in modifierTokens(in: scene) {
@@ -329,7 +329,7 @@
                 PhysicalKey(keyCode: 122, label: "f1", x: 1.05, y: 0),
                 PhysicalKey(keyCode: PhysicalKey.unmappedKeyCode, label: "touch id", x: 2.1, y: 0),
                 PhysicalKey(keyCode: 18, label: "1", x: 0, y: 1.05),
                 PhysicalKey(keyCode: 57, label: "caps", x: 0, y: 2.1, width: 1.5),
             ]
         )
 
@@ -361,7 +361,7 @@
                 PhysicalKey(keyCode: 56, label: "shift", x: 0, y: 3.15, width: 2),
                 PhysicalKey(keyCode: 59, label: "control", x: 2.05, y: 3.15),
                 PhysicalKey(keyCode: 58, label: "option", x: 3.1, y: 3.15),
                 PhysicalKey(keyCode: 55, label: "command", x: 4.15, y: 3.15),
             ]
         )
         let scene = KeyboardStageSceneBuilder.make(
@@ -393,7 +393,7 @@
             name: "Keyboard Stage Selected Keymap Legends",
             keys: [
                 PhysicalKey(keyCode: 18, label: "1", x: 0, y: 0),
                 PhysicalKey(keyCode: 19, label: "2", x: 1.05, y: 0),
             ]
         )
         let keymap = LogicalKeymap(
@@ -521,6 +521,21 @@
         XCTAssertEqual(otherKey, originalOtherKey)
     }
 
+    func testReleaseReboundLiftsTheCapAboveRest() throws {
+        let scene = makeScene(moment: .capsInstalled)
+        let responsiveScene = scene.applyingInteraction(
+            KeyboardStageInteractionLevels(pressed: [57: -0.025], held: [:])
+        )
+        let caps = try capsKey(in: responsiveScene)
+        let baseCaps = try capsKey(in: scene)
+
+        // The underdamped release dips slightly negative; the cap must rise
+        // a hair above its rest position, with no residual press styling.
+        XCTAssertLessThan(caps.translation.y, baseCaps.translation.y)
+        XCTAssertEqual(caps.interactionLevel, 0)
+        XCTAssertEqual(caps.pressure, baseCaps.pressure)
+    }
+
     func testLivePressRespondsOnANeutralNonCapsKey() throws {
         let scene = makeScene(moment: .capsInstalled)
         let neutral = try XCTUnwrap(scene.keys.first { key in
@@ -574,7 +589,7 @@
     func testLivePressUsesAnAccentFaceAndReadableLegendThroughoutRelease() {
         let roles: [KeyboardStageKeyRole] = [
             .standard, .modifier, .dimmed, .recommended, .escape,
             .hyper, .launcher, .installed,
         ]
         let levels = stride(from: Float(0.005), through: 1, by: 0.005)
         for appearance in [KeyboardStageDisplayMode.Appearance.light, .dark] {
@@ -605,7 +620,7 @@
 
     func testInstructionalRolesKeepAPhysicalKeyFaceAndUseTheRimForEmphasis() {
         let roles: [KeyboardStageKeyRole] = [
             .recommended, .escape, .hyper, .launcher, .installed,
         ]
 
         for appearance in [KeyboardStageDisplayMode.Appearance.light, .dark] {
@@ -671,7 +686,7 @@
             .hyperApplying,
             .hyperInstalled,
             .launcher,
             .handoff,
         ]
     }