Guard against models providing quads with null orientations.

src/main/java/appeng/thirdparty/codechicken/lib/model/Quad.java

@@ -46,7 +46,6 @@ public class Quad implements IVertexProducer, ISmartVertexConsumer
 	public CachedFormat format;
 
 	public int tintIndex = -1;
-	// TODO, sometimes this is null because people don't do models properly.
 	public EnumFacing orientation;
 	public boolean diffuseLighting = true;
 	public TextureAtlasSprite sprite;
@@ -130,6 +129,10 @@ public class Quad implements IVertexProducer, ISmartVertexConsumer
 			{
 				this.vertexIndex = 0;
 				this.full = true;
+				if(orientation == null)
+				{
+				    calculateOrientation(false);
+                }
 			}
 		}
 	}
@@ -195,7 +198,17 @@ public class Quad implements IVertexProducer, ISmartVertexConsumer
 			vec[1] = (float) MathHelper.clamp( vec[1], bb.minY, bb.maxY );
 			vec[2] = (float) MathHelper.clamp( vec[2], bb.minZ, bb.maxZ );
 		}
+		calculateOrientation(true);
+	}
 
+    /**
+     * Re-calculates the Orientation of this quad,
+     * optionally the normal vector.
+     *
+     * @param setNormal If the normal vector should be updated.
+     */
+	public void calculateOrientation( boolean setNormal )
+    {
         this.v1.set( this.vertices[3].vec );
         this.t.set( this.vertices[1].vec );
         this.v1.sub( this.t );
@@ -207,7 +220,7 @@ public class Quad implements IVertexProducer, ISmartVertexConsumer
         this.normal.cross( this.v2, this.v1 );
         this.normal.normalize();
 
-		if( this.format.hasNormal )
+        if( this.format.hasNormal && setNormal)
         {
             for( Vertex vertex : this.vertices )
             {