diff --git a/models/PhotoMosaic.php b/models/PhotoMosaic.php
index 05b25169..f4e13392 100644
--- a/models/PhotoMosaic.php
+++ b/models/PhotoMosaic.php
@@ -10,11 +10,13 @@ class PhotoMosaic
 {
 	const NUM_DAYS_CUTOFF = 7;
 	private AssetIterator $iterator;
+	private $layouts;
 	private $queue = [];
 
 	public function __construct(AssetIterator $iterator)
 	{
 		$this->iterator = $iterator;
+		$this->layouts = $this->availableLayouts();
 	}
 
 	public function __destruct()
@@ -22,6 +24,28 @@ class PhotoMosaic
 		$this->iterator->clean();
 	}
 
+	private function availableLayouts()
+	{
+		static $layouts = [
+			// Single panorama
+			'panorama' => [Image::TYPE_PANORAMA],
+
+			// Big-small juxtapositions
+			'portrait' => [Image::TYPE_PORTRAIT, Image::TYPE_LANDSCAPE, Image::TYPE_LANDSCAPE],
+			'landscape' => [Image::TYPE_LANDSCAPE, Image::TYPE_LANDSCAPE, Image::TYPE_LANDSCAPE],
+
+			// Single row of three
+			'landscapes' => [Image::TYPE_LANDSCAPE, Image::TYPE_LANDSCAPE, Image::TYPE_LANDSCAPE],
+			'portraits' => [Image::TYPE_PORTRAIT, Image::TYPE_PORTRAIT, Image::TYPE_PORTRAIT],
+
+			// Fallback layouts
+			'duo' => [Image::TYPE_LANDSCAPE, Image::TYPE_LANDSCAPE],
+			'single' => [Image::TYPE_LANDSCAPE | Image::TYPE_PORTRAIT],
+		];
+
+		return $layouts;
+	}
+
 	private static function daysApart(Image $a, Image $b)
 	{
 		return $a->getDateCaptured()->diff($b->getDateCaptured())->days;