fix(android): animate visible idle sphere efficiently

CHANGELOG.md

@@ -18,6 +18,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/), and this
 
 ### Fixed
 
+- **The Android Sphere remains gently animated while visibly idle.** New chats and the ambient Sphere behind messages now use a low-cost layer breath, while hidden/backgrounded and motion-disabled surfaces stay still and active agent/voice states retain their full procedural animation.
 - **Desktop daemon connections recover instead of exiting after an interrupted Relay socket.** Healthy daemons retry through Relay restarts and repeated failed reconnect attempts, oversized desktop-tool results fail within a bounded response instead of closing the shared WebSocket, and terminal failures leave an accurate stopped status for the tray.
 - **Desktop computer control follows Hermes' current CUA Driver contract.** CUA Driver 0.20 and newer are accepted when their manifest, daemon/MCP arguments, required tools, and canonical path remain compatible, and Windows sessions use the manifest-declared direct standard-mode runtime instead of a potentially stale machine-wide daemon. Current 0.21 installations no longer fall back solely because of an obsolete upper version pin or daemon contract.
 

app/src/main/kotlin/com/hermesandroid/relay/ui/components/MorphingSphere.kt

@@ -14,6 +14,7 @@ import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableFloatStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.withFrameNanos
+import androidx.compose.ui.graphics.graphicsLayer
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.clipToBounds
 import androidx.compose.ui.geometry.Offset
@@ -25,6 +26,8 @@ import androidx.compose.ui.text.rememberTextMeasurer
 import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import com.hermesandroid.relay.ui.theme.LocalBrand
+import kotlinx.coroutines.delay
+import kotlin.math.sin
 
 /**
  * ASCII morphing sphere — the visual embodiment of the AI agent.
@@ -53,6 +56,32 @@ import com.hermesandroid.relay.ui.theme.LocalBrand
 private const val SPHERE_TIME_UNITS_PER_SEC = 1f
 private const val SPHERE_TWO_PI = 6.2832f
 private const val SPHERE_COLOR_RADIANS_PER_SEC = 0.7854f
+private const val SPHERE_IDLE_BREATH_RADIANS_PER_SEC = 0.72f
+private const val SPHERE_IDLE_BREATH_SCALE = 0.012f
+private const val SPHERE_IDLE_LAYER_FRAME_INTERVAL_MS = 184L
+
+internal enum class SphereMotionMode {
+    Still,
+    AmbientLayer,
+    Procedural,
+}
+
+internal fun sphereMotionMode(
+    state: SphereState,
+    voiceMode: Boolean,
+    motionVisible: Boolean,
+    fixedTime: Float?,
+    fixedColorPhase: Float?,
+): SphereMotionMode {
+    if (!motionVisible || fixedTime != null || fixedColorPhase != null) {
+        return SphereMotionMode.Still
+    }
+    return if (state == SphereState.Idle && !voiceMode) {
+        SphereMotionMode.AmbientLayer
+    } else {
+        SphereMotionMode.Procedural
+    }
+}
 
 @Composable
 fun MorphingSphere(
@@ -64,7 +93,8 @@ fun MorphingSphere(
     voiceMode: Boolean = false,
     skin: SphereSkin = LocalSphereSkin.current,
     fixedTime: Float? = null,
-    fixedColorPhase: Float? = null
+    fixedColorPhase: Float? = null,
+    motionVisible: Boolean = true,
 ) {
     val brand = LocalBrand.current
     // Gate reactive inputs on what the skin declares it honors — this is the
@@ -104,16 +134,21 @@ fun MorphingSphere(
     val cg2 by animateFloatAsState(targetC.g2, spec, label = "cg2")
     val cb2 by animateFloatAsState(targetC.b2, spec, label = "cb2")
 
-    // Continuous motion runs only for active agent/voice states. Idle is a
-    // stable frame: the 58x34 text grid is expensive enough that even a
-    // throttled cosmetic drift dominated measured screen-on CPU. Active states
-    // retain full display-rate motion and dt-based timing.
+    // Active states retain the full procedural animation. Visible Idle uses a
+    // lightweight graphics-layer breath: redrawing the 58x34 glyph grid just
+    // for ambient drift was the measured screen-on hotspot, while transforming
+    // its cached layer preserves the intended living Sphere at far lower cost.
     val animatedTime = remember { mutableFloatStateOf(0f) }
     val animatedColorPhase = remember { mutableFloatStateOf(0f) }
-    val fullFrameRate = state != SphereState.Idle || effVoiceMode
-    val driveAnimation = (fixedTime == null || fixedColorPhase == null) && fullFrameRate
-    if (driveAnimation) {
-        LaunchedEffect(fullFrameRate) {
+    val motionMode = sphereMotionMode(
+        state = state,
+        voiceMode = effVoiceMode,
+        motionVisible = motionVisible,
+        fixedTime = fixedTime,
+        fixedColorPhase = fixedColorPhase,
+    )
+    if (motionMode == SphereMotionMode.Procedural) {
+        LaunchedEffect(motionMode) {
             var lastNanos = withFrameNanos { it }
             while (true) {
                 val now = withFrameNanos { it }
@@ -127,6 +162,25 @@ fun MorphingSphere(
             }
         }
     }
+    val idleBreathPhase = remember { mutableFloatStateOf(0f) }
+    LaunchedEffect(motionMode) {
+        if (motionMode != SphereMotionMode.AmbientLayer) {
+            idleBreathPhase.floatValue = 0f
+            return@LaunchedEffect
+        }
+        var lastNanos = withFrameNanos { it }
+        while (true) {
+            val now = withFrameNanos { it }
+            val dtSec = (now - lastNanos).coerceAtLeast(0L) / 1_000_000_000f
+            lastNanos = now
+            idleBreathPhase.floatValue =
+                (idleBreathPhase.floatValue + dtSec * SPHERE_IDLE_BREATH_RADIANS_PER_SEC) %
+                SPHERE_TWO_PI
+            // The frame wait plus this delay caps the gentle layer-only pulse
+            // near 5fps while active procedural states retain display-rate motion.
+            delay(SPHERE_IDLE_LAYER_FRAME_INTERVAL_MS)
+        }
+    }
 
     val time = fixedTime ?: animatedTime.floatValue
     val colorPhase = fixedColorPhase ?: animatedColorPhase.floatValue
@@ -138,7 +192,18 @@ fun MorphingSphere(
     val textMeasurer = rememberTextMeasurer(cacheSize = 64)
     val glyphStrings = remember { HashMap<Char, String>(32) }
 
-    Canvas(modifier = modifier.fillMaxSize().clipToBounds()) {
+    Canvas(
+        modifier = modifier
+            .fillMaxSize()
+            .graphicsLayer {
+                if (motionMode == SphereMotionMode.AmbientLayer) {
+                    val scale = 1f + sin(idleBreathPhase.floatValue) * SPHERE_IDLE_BREATH_SCALE
+                    scaleX = scale
+                    scaleY = scale
+                }
+            }
+            .clipToBounds(),
+    ) {
         val canvasW = size.width
         val canvasH = size.height
         val cellW = canvasW / cols

app/src/main/kotlin/com/hermesandroid/relay/ui/components/avatar/SphereAvatar.kt

@@ -1,9 +1,12 @@
 package com.hermesandroid.relay.ui.components.avatar
 
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
 import androidx.compose.ui.Modifier
 import com.hermesandroid.relay.ui.components.MorphingSphere
 import com.hermesandroid.relay.ui.components.SphereReactivity
+import com.hermesandroid.relay.util.AppForegroundTracker
 
 /**
  * Default ambient visualization — the ASCII [MorphingSphere].
@@ -34,6 +37,7 @@ object SphereAvatar : AgentAvatar {
 
     @Composable
     override fun Render(state: AvatarRenderState, modifier: Modifier) {
+        val appForeground by AppForegroundTracker.isForeground.collectAsState()
         MorphingSphere(
             modifier = modifier,
             state = state.state,
@@ -46,6 +50,7 @@ object SphereAvatar : AgentAvatar {
             // call did with fixedTime/fixedColorPhase = 0f.
             fixedTime = if (state.paused) 0f else null,
             fixedColorPhase = if (state.paused) 0f else null,
+            motionVisible = appForeground,
         )
     }
 }

app/src/test/kotlin/com/hermesandroid/relay/ui/components/MorphingSphereMotionPolicyTest.kt

@@ -0,0 +1,44 @@
+package com.hermesandroid.relay.ui.components
+
+import org.junit.Assert.assertEquals
+import org.junit.Test
+
+class MorphingSphereMotionPolicyTest {
+    @Test
+    fun `visible idle sphere uses lightweight ambient motion`() {
+        assertEquals(
+            SphereMotionMode.AmbientLayer,
+            sphereMotionMode(
+                state = SphereState.Idle,
+                voiceMode = false,
+                motionVisible = true,
+                fixedTime = null,
+                fixedColorPhase = null,
+            ),
+        )
+    }
+
+    @Test
+    fun `hidden or paused idle sphere is still`() {
+        assertEquals(
+            SphereMotionMode.Still,
+            sphereMotionMode(SphereState.Idle, false, false, null, null),
+        )
+        assertEquals(
+            SphereMotionMode.Still,
+            sphereMotionMode(SphereState.Idle, false, true, 0f, 0f),
+        )
+    }
+
+    @Test
+    fun `visible active and voice states keep procedural motion`() {
+        assertEquals(
+            SphereMotionMode.Procedural,
+            sphereMotionMode(SphereState.Thinking, false, true, null, null),
+        )
+        assertEquals(
+            SphereMotionMode.Procedural,
+            sphereMotionMode(SphereState.Idle, true, true, null, null),
+        )
+    }
+}

docs/dev-loop.md

@@ -68,6 +68,25 @@ Rule of thumb: where a surface is CI-gateable, write the **failing test first**
 is the deliberate exception — CI only covers lint + unit there, so on-device
 verification stays a manual maintainer step and a fix is never "done" from CI alone.
 
+### Emulator UI evidence
+
+Hermes Android is dark-mode-first. Before emulator screenshots, animation
+review, or renderer performance measurements, explicitly enable Android dark
+mode and restart the app so evidence is not captured in the emulator's light
+default:
+
+```bash
+adb -s <emulator-serial> shell cmd uimode night yes
+adb -s <emulator-serial> shell am force-stop com.axiomlabs.hermesrelay.sideload
+adb -s <emulator-serial> shell am start -n \
+  com.axiomlabs.hermesrelay.sideload/com.hermesandroid.relay.MainActivity
+adb -s <emulator-serial> shell cmd uimode night
+```
+
+Confirm the final command reports `Night mode: yes` before capturing evidence.
+Use host GPU acceleration where available; software rendering is useful for
+compatibility but is not representative performance evidence.
+
 ## Local bridge: `scripts/start-issue.sh`
 
 ```bash