DIRECTOR: Add support for "get/set picture of cast"

engines/director/castmember.cpp

@@ -550,6 +550,30 @@ Common::String BitmapCastMember::formatInfo() {
 	);
 }
 
+PictureReference *BitmapCastMember::getPicture() const {
+	auto picture = new PictureReference;
+
+	// Not sure if we can make the assumption that the owning
+	// BitmapCastMember will live as long as any reference,
+	// so we'll make a copy of the Picture.
+	picture->_picture = new Picture(*_picture);
+
+	return picture;
+}
+
+void BitmapCastMember::setPicture(PictureReference &picture) {
+	delete _picture;
+	_picture = new Picture(*picture._picture);
+
+	// Force redither
+	delete _ditheredImg;
+	_ditheredImg = nullptr;
+
+	// Make sure we get redrawn
+	setModified(true);
+	// TODO: Should size be adjusted?
+}
+
 void BitmapCastMember::setPicture(Image::ImageDecoder &image, bool adjustSize) {
 	delete _picture;
 	_picture = new Picture(image);

engines/director/castmember.h

@@ -137,6 +137,8 @@ public:
 
 	Common::String formatInfo() override;
 
+	PictureReference *getPicture() const;
+	void setPicture(PictureReference &picture);
 	void setPicture(Image::ImageDecoder &image, bool adjustSize);
 
 	Picture *_picture = nullptr;

engines/director/lingo/lingo-builtins.cpp

@@ -1767,9 +1767,9 @@ void LB::b_objectp(int nargs) {
 }
 
 void LB::b_pictureP(int nargs) {
-	g_lingo->pop();
-	warning("STUB: b_pictureP");
-	g_lingo->push(Datum(0));
+	Datum d = g_lingo->pop();
+	Datum res((d.type == PICTUREREF) ? 1 : 0);
+	g_lingo->push(res);
 }
 
 void LB::b_stringp(int nargs) {

engines/director/lingo/lingo-object.cpp

@@ -963,7 +963,8 @@ Datum BitmapCastMember::getField(int field) {
 		d = _clut;
 		break;
 	case kThePicture:
-		warning("STUB: BitmapCastMember::getField(): Unprocessed getting field \"%s\" of cast %d", g_lingo->field2str(field), _castId);
+		d.type = PICTUREREF;
+		d.u.picture = getPicture();
 		break;
 	default:
 		d = CastMember::getField(field);
@@ -993,7 +994,12 @@ bool BitmapCastMember::setField(int field, const Datum &d) {
 		_clut = d.asInt();
 		return true;
 	case kThePicture:
-		warning("STUB: BitmapCastMember::setField(): Unprocessed setting field \"%s\" of cast %d", g_lingo->field2str(field), _castId);
+		if (d.type == PICTUREREF && d.u.picture != nullptr) {
+			setPicture(*d.u.picture);
+			return true;
+		} else {
+			warning("BitmapCastMember::setField(): Wrong Datum type %d for kThePicture (or nullptr)", d.type);
+		}
 		return false;
 	default:
 		break;

engines/director/lingo/lingo.cpp

@@ -938,6 +938,9 @@ void Datum::reset() {
 		case MENUREF:
 			delete u.menu;
 			break;
+		case PICTUREREF:
+			delete u.picture;
+			break;
 		default:
 			warning("Datum::reset(): Unprocessed REF type %d", type);
 			break;
@@ -1163,6 +1166,9 @@ Common::String Datum::asString(bool printonly) const {
 	case MENUREF:
 		s = Common::String::format("menu(%d, %d)", u.menu->menuIdNum, u.menu->menuItemIdNum);
 		break;
+	case PICTUREREF:
+		s = Common::String::format("picture: %p", (void*)u.picture->_picture);
+		break;
 	default:
 		warning("Incorrect operation asString() for type: %s", type2str());
 	}
@@ -1228,6 +1234,8 @@ const char *Datum::type2str(bool ilk) const {
 		return ilk ? "object" : "OBJECT";
 	case PARRAY:
 		return ilk ? "proplist" : "PARRAY";
+	case PICTUREREF:
+		return ilk ? "picture" :  "PICTUREREF";
 	case POINT:
 		return ilk ? "point" : "POINT";
 	case PROPREF:
@@ -1267,6 +1275,8 @@ int Datum::equalTo(Datum &d, bool ignoreCase) const {
 		return u.obj == d.u.obj;
 	case CASTREF:
 		return *u.cast == *d.u.cast;
+	case PICTUREREF:
+		return 0; // Original always returns 0 on picture reference comparison
 	default:
 		break;
 	}

engines/director/lingo/lingo.h

@@ -41,6 +41,7 @@ namespace Director {
 
 struct ChunkReference;
 struct MenuReference;
+struct PictureReference;
 struct TheEntity;
 struct TheEntityField;
 struct LingoArchive;
@@ -144,6 +145,7 @@ struct Datum {	/* interpreter stack type */
 		ChunkReference *cref; /* CHUNKREF */
 		CastMemberID *cast;	/* CASTREF, FIELDREF */
 		MenuReference *menu; /* MENUREF	*/
+		PictureReference *picture; /* PICTUREREF */
 	} u;
 
 	int *refCount;
@@ -209,6 +211,13 @@ struct MenuReference {
 	MenuReference();
 };
 
+struct PictureReference {
+	Picture *_picture = nullptr;
+	~PictureReference() {
+		delete _picture;
+	}
+};
+
 struct PCell {
 	Datum p;
 	Datum v;

engines/director/lingo/tests/equality.lingo

@@ -19,3 +19,8 @@ scummvmAssert("<Object:#FileIO" > 0)
 
 -- Invalid comparisons should return FALSE
 scummvmAssert(not (#test <= 0))
+
+-- Picture comparisons are always false, even between the exact same cast.
+set a to the picture of cast 1
+scummvmAssert(a <> a)
+scummvmAssert(a <> the picture of cast 1)   -- always false

engines/director/types.h

@@ -357,6 +357,7 @@ enum DatumType {
 	MENUREF,
 	OBJECT,
 	PARRAY,
+	PICTUREREF,
 	POINT,
 	PROPREF,
 	RECT,