Custom resolution per mode, as in Bannerlator

Resolution gains Custom…: a width × height box (320×240 to 3840×2160, evened) with one-tap
presets for 4:3 (960×720, 1024×768, 1280×960), 16:10 (1280×800) and 16:9. A custom size replaces
the cap and the shape for that mode - the Shape row greys out and says so - and the compositor fits
it to the panel with bars where the shapes differ. Choosing any cap clears it. The device report
lists it for both modes.

app/src/main/java/com/steamdeck/launcher/MainActivity.kt

@@ -149,6 +149,7 @@ class MainActivity : ComponentActivity() {
     // The mode whose settings dialog is open, with what it shows; refreshed by openModeSettings().
     private var settingsMode by mutableStateOf<String?>(null)
     private var resolutionCap by mutableStateOf(1080)
+    private var customResolution by mutableStateOf<Pair<Int, Int>?>(null)
     private var fexPreset by mutableStateOf("")
     private var steamChannel by mutableStateOf("publicbeta")
     private var theme by mutableStateOf("paper")
@@ -414,7 +415,7 @@ class MainActivity : ComponentActivity() {
     private fun ModeSettingsHost(mode: String) {
         ModeSettingsPage(
             ModeSettings(
-                mode = mode, resolutionCap = resolutionCap, shapeMode = shapeMode,
+                mode = mode, resolutionCap = resolutionCap, customResolution = customResolution, shapeMode = shapeMode,
                 hdr = hdrOn, hdrReason = hdrReason,
                 linuxRows = linuxRows,
                 linuxSelected = if (mode == SessionService.MODE_STEAM) linuxSteam else linuxDesktop,
@@ -436,6 +437,7 @@ class MainActivity : ComponentActivity() {
             ),
             ModeSettingsActions(
                 onResolution = { cap -> SessionPrefs.setResolutionCap(this, mode, cap); resolutionCap = cap },
+                onCustomResolution = { size -> SessionPrefs.setCustomResolution(this, mode, size); customResolution = size },
                 onShape = { shape -> SessionPrefs.setShapeMode(this, shape); shapeMode = shape },
                 onHdr = { on -> SessionPrefs.setHdr(this, mode, on); hdrOn = on },
                 onSelectLinux = { id -> SessionPrefs.setLinuxDriver(this, mode, id); refreshDrivers() },
@@ -530,6 +532,7 @@ class MainActivity : ComponentActivity() {
         showApps = false
         refreshDrivers()
         resolutionCap = SessionPrefs.resolutionCap(this, mode)
+        customResolution = SessionPrefs.customResolution(this, mode)
         fexPreset = SessionPrefs.fexPreset(this)
         steamChannel = SessionPrefs.steamChannel(this)
         addedGamesDirs = SessionPrefs.addedGamesDirs(this)

app/src/main/java/com/steamdeck/launcher/SessionActivity.kt

@@ -456,6 +456,8 @@ class SessionActivity : ComponentActivity(), SurfaceHolder.Callback {
         // handheld panel. The mode's settings (the cog beside Play / Desktop) can change
         // the cap or lift it to the panel.
         val mode = SessionPrefs.prefMode(intent.getStringExtra(SessionService.EXTRA_MODE) ?: SessionService.MODE_STEAM)
+        // A custom resolution is taken as given; the compositor fits it to the panel.
+        SessionPrefs.customResolution(this, mode)?.let { return it }
         val cap = SessionPrefs.resolutionCap(this, mode)
         val height = (if (cap <= 0) panelH else minOf(panelH, cap.toFloat())).toInt()
         val width = (height * aspect).toInt()

app/src/main/java/com/steamdeck/launcher/core/DeviceReport.kt

@@ -109,6 +109,8 @@ object DeviceReport {
         k("Session output", SessionState.outputSize?.let { "${it.first}x${it.second}" })
         k("Session refresh", String.format(Locale.US, "%.2f Hz", SessionState.refreshHz))
         k("Shape setting", SessionPrefs.shapeMode(context))
+        k("Custom resolution (Steam)", SessionPrefs.customResolution(context, SessionService.MODE_STEAM)?.let { "${it.first}x${it.second}" } ?: "off")
+        k("Custom resolution (Desktop)", SessionPrefs.customResolution(context, SessionService.MODE_DESKTOP)?.let { "${it.first}x${it.second}" } ?: "off")
         k("Foldable", context.packageManager.hasSystemFeature("android.hardware.sensor.hinge_angle"))
 
         h("Drivers")

app/src/main/java/com/steamdeck/launcher/session/SessionPrefs.kt

@@ -308,6 +308,27 @@ object SessionPrefs {
         prefs(context).edit().putInt("resolutionCap.$mode", cap).apply()
     }
 
+    /**
+     * A fixed size for the session's display, per mode, or null. When set it replaces both the
+     * cap and the shape: the compositor fits it to the panel with bars where the shapes differ.
+     */
+    fun customResolution(context: Context, mode: String): Pair<Int, Int>? =
+        parseResolution(prefs(context).getString("customRes.$mode", null))
+
+    fun setCustomResolution(context: Context, mode: String, size: Pair<Int, Int>?) {
+        prefs(context).edit().putString("customRes.$mode", size?.let { "${it.first}x${it.second}" }).apply()
+    }
+
+    /** "1024x768" (or ×, or *) to an even size inside 320x240..3840x2160; anything else is null. */
+    fun parseResolution(text: String?): Pair<Int, Int>? {
+        val parts = text?.trim()?.split('x', 'X', '×', '*')?.map { it.trim() } ?: return null
+        if (parts.size != 2) return null
+        val w = parts[0].toIntOrNull() ?: return null
+        val h = parts[1].toIntOrNull() ?: return null
+        if (w !in 320..3840 || h !in 240..2160) return null
+        return Pair(w and 1.inv(), h and 1.inv())
+    }
+
     /**
      * What the desktop shell composites with: pixman (software, the default - the Adreno stand-in
      * is not a DRM render node, so labwc's gbm allocator cannot use it), or gles2 / vulkan for a

app/src/main/java/com/steamdeck/launcher/ui/ModeSettingsDialog.kt

@@ -6,6 +6,10 @@ import androidx.compose.foundation.layout.size
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
@@ -18,6 +22,8 @@ class DriverRow(val id: String, val name: String, val detail: String, val remova
 class ModeSettings(
     val mode: String,
     val resolutionCap: Int,
+    /** A fixed session size, or null for the cap and shape. */
+    val customResolution: Pair<Int, Int>? = null,
     val shapeMode: String,
     val hdr: Boolean,
     val hdrReason: String?,
@@ -50,6 +56,8 @@ class AddedGameRow(val folderPath: String, val folderName: String, val exePath:
 
 class ModeSettingsActions(
     val onResolution: (Int) -> Unit,
+    /** Null clears it. */
+    val onCustomResolution: (Pair<Int, Int>?) -> Unit = {},
     val onShape: (String) -> Unit,
     val onHdr: (Boolean) -> Unit,
     val onSelectLinux: (String) -> Unit,
@@ -88,16 +96,25 @@ fun ModeSettingsPage(s: ModeSettings, a: ModeSettingsActions) {
     ) {
         SettingsGroup("Display") {
             val default = SessionPrefs.defaultResolutionCap(s.mode)
+            var editCustom by remember { mutableStateOf(false) }
+            val custom = s.customResolution
             ChoiceRow(
                 host, "res", "Resolution", "Applies next session.",
                 listOf(720 to "Up to 720p", 900 to "Up to 900p", 1080 to "Up to 1080p", 0 to "The panel's own")
-                    .map { (cap, label) -> cap to (if (cap == default) "$label - the default" else label) },
-                s.resolutionCap, note = "720p can improve menu responsiveness.",
-                onPick = a.onResolution,
+                    .map { (cap, label) -> cap to (if (cap == default) "$label - the default" else label) } +
+                    (CUSTOM to (custom?.let { "Custom · ${it.first}×${it.second}" } ?: "Custom…")),
+                if (custom != null) CUSTOM else s.resolutionCap, note = "720p can improve menu responsiveness.",
+                onPick = { v -> if (v == CUSTOM) editCustom = true else { a.onCustomResolution(null); a.onResolution(v) } },
             )
             ChoiceRow(
-                host, "shape", "Shape", "The panel's shape stays at 16:9 or wider; pick Exactly this panel for a 4:3 or 3:2 screen.",
-                com.steamdeck.launcher.session.SessionPrefs.shapeChoices, s.shapeMode, onPick = a.onShape,
+                host, "shape", "Shape",
+                if (custom != null) "Set by the custom resolution." else "The panel's shape stays at 16:9 or wider; pick Exactly this panel for a 4:3 or 3:2 screen.",
+                com.steamdeck.launcher.session.SessionPrefs.shapeChoices, s.shapeMode, enabled = custom == null, onPick = a.onShape,
+            )
+            if (editCustom) CustomResolutionDialog(
+                initial = custom,
+                onSave = { size -> editCustom = false; a.onCustomResolution(size) },
+                onDismiss = { editCustom = false },
             )
         }
         SettingsGroup("HDR") {
@@ -267,3 +284,59 @@ private fun DriverRowMenu(
         }
     }
 }
+
+/** The Resolution menu's "Custom…" entry. */
+private const val CUSTOM = -1
+
+/** Width × height for the session, with the common handheld shapes one tap away. */
+@OptIn(androidx.compose.foundation.layout.ExperimentalLayoutApi::class)
+@Composable
+private fun CustomResolutionDialog(initial: Pair<Int, Int>?, onSave: (Pair<Int, Int>) -> Unit, onDismiss: () -> Unit) {
+    var w by remember { mutableStateOf(initial?.first?.toString() ?: "") }
+    var h by remember { mutableStateOf(initial?.second?.toString() ?: "") }
+    val parsed = SessionPrefs.parseResolution("${w}x$h")
+    androidx.compose.material3.AlertDialog(
+        onDismissRequest = onDismiss,
+        title = { Text("Custom resolution") },
+        text = {
+            androidx.compose.foundation.layout.Column {
+                Text(
+                    "The session's display size. It replaces the cap and the shape; a size that does not match the panel's shape gets bars.",
+                    fontSize = 13.sp, color = MaterialTheme.colorScheme.onSurfaceVariant,
+                )
+                androidx.compose.foundation.layout.Row(
+                    verticalAlignment = androidx.compose.ui.Alignment.CenterVertically,
+                    modifier = Modifier.padding(top = 12.dp),
+                ) {
+                    val numbers = androidx.compose.foundation.text.KeyboardOptions(keyboardType = androidx.compose.ui.text.input.KeyboardType.Number)
+                    androidx.compose.material3.OutlinedTextField(
+                        w, { v -> w = v.filter(Char::isDigit).take(4) }, label = { Text("Width") },
+                        singleLine = true, keyboardOptions = numbers, modifier = Modifier.weight(1f),
+                    )
+                    Text("×", fontSize = 18.sp, modifier = Modifier.padding(horizontal = 10.dp))
+                    androidx.compose.material3.OutlinedTextField(
+                        h, { v -> h = v.filter(Char::isDigit).take(4) }, label = { Text("Height") },
+                        singleLine = true, keyboardOptions = numbers, modifier = Modifier.weight(1f),
+                    )
+                }
+                androidx.compose.foundation.layout.FlowRow(
+                    horizontalArrangement = androidx.compose.foundation.layout.Arrangement.spacedBy(6.dp),
+                    modifier = Modifier.padding(top = 10.dp),
+                ) {
+                    for ((pw, ph, tag) in listOf(Triple(960, 720, "4:3"), Triple(1024, 768, "4:3"), Triple(1280, 960, "4:3"), Triple(1280, 800, "16:10"), Triple(1152, 648, "16:9"), Triple(1280, 720, "16:9"))) {
+                        androidx.compose.material3.AssistChip(
+                            onClick = { w = pw.toString(); h = ph.toString() },
+                            label = { Text("$pw×$ph · $tag", fontSize = 12.sp) },
+                        )
+                    }
+                }
+                if (parsed == null && (w.isNotEmpty() || h.isNotEmpty())) Text(
+                    "Between 320×240 and 3840×2160.", fontSize = 12.sp, color = MaterialTheme.colorScheme.error,
+                    modifier = Modifier.padding(top = 6.dp),
+                )
+            }
+        },
+        confirmButton = { androidx.compose.material3.TextButton(enabled = parsed != null, onClick = { parsed?.let(onSave) }) { Text("Use") } },
+        dismissButton = { androidx.compose.material3.TextButton(onClick = onDismiss) { Text("Cancel") } },
+    )
+}