render item frame contents with the item geometry like vanilla ItemFrameRenderer (fixed context, 8 rotations, all facings), frame block models, map contents incl. pixelpics photos, invisible frames, head skins/banner patterns from item meta

src/main/java/eu/mhsl/minecraft/pixelpics/utils/ImageMapRenderer.java

@@ -109,6 +109,11 @@ public class ImageMapRenderer extends MapRenderer {
         return Math.min(0.999, noise * 0.7 + sweep * 0.3);
     }
 
+    /** The blank-film map colour a photo shows while it is still being rendered. */
+    public static byte filmColor() {
+        return film();
+    }
+
     private static byte film() {
         if (!filmResolved) {
             filmIndex = MapColorPalette.mapIndex(MapColorPalette.nearestPos(206, 202, 190));

src/main/java/eu/mhsl/minecraft/pixelpics/utils/MapColorPalette.java

@@ -17,6 +17,7 @@ public final class MapColorPalette {
     private static byte[] indices;
     private static int[] rgb;
     private static double[][] lab;
+    private static int[] argbByIndex; // all 256 map colour bytes → ARGB (transparent slots alpha 0)
 
     private MapColorPalette() {}
 
@@ -48,9 +49,24 @@ public final class MapColorPalette {
             rgb[i] = rgbs.get(i);
             lab[i] = labs.get(i);
         }
+        argbByIndex = new int[256];
+        for (int i = 0; i < 256; i++) {
+            try {
+                Color c = MapPalette.getColor((byte) i);
+                argbByIndex[i] = c.getAlpha() < 255 ? 0 : (0xFF << 24) | (c.getRGB() & 0xFFFFFF);
+            } catch (Throwable t) {
+                argbByIndex[i] = 0;
+            }
+        }
         initialized = true;
     }
 
+    /** ARGB of a raw map colour byte as the client draws it; transparent slots are 0. */
+    public static int argb(byte mapColor) {
+        ensure();
+        return argbByIndex[mapColor & 0xFF];
+    }
+
     public static int size() {
         ensure();
         return indices.length;