materials : fix shaders on preview sphere of materials

hrt/prefab/Material.hx

@@ -59,11 +59,11 @@ class Material extends Prefab {
 		return r;
 	}
 
-	public function getMaterials() {
+	public function getMaterials(includePreviewMats : Bool = false) {
 		var mats = findFirstLocal3d().getMaterials();
 
 		#if editor
-		if (mats != null) {
+		if (!includePreviewMats && mats != null) {
 			var idx = mats.length - 1;
 			while (idx >= 0) {
 				if (mats[idx].name == "previewMat")

hrt/prefab/Shader.hx

@@ -97,7 +97,7 @@ class Shader extends Prefab {
 
 		if( Std.isOfType(parent, Material) ) {
 			var material : Material = cast parent;
-			for( m in material.getMaterials() )
+			for( m in material.getMaterials(true) )
 					callb(null, m);
 		} else {
 			var objs = [];