ACCESS: Implemented buildRow for vertical screen scrolling

2 files changed, 23 insertions, 3 deletions

diff --git a/engines/access/asurface.cpp b/engines/access/asurface.cpp
index dbbf119171..96cb1991be 100644
--- a/engines/access/asurface.cpp
+++ b/engines/access/asurface.cpp
@@ -337,12 +337,12 @@ void ASurface::moveBufferRight() {
 
 void ASurface::moveBufferUp() {
 	byte *p = (byte *)getPixels();
-	Common::copy(p + w, p + (w * h), p);
+	Common::copy(p + (w * TILE_HEIGHT), p + (w * h), p);
 }
 
 void ASurface::moveBufferDown() {
 	byte *p = (byte *)getPixels();
-	Common::copy_backward(p, p + (w * (h - 1)), p + (w * h));
+	Common::copy_backward(p, p + (w * (h - TILE_HEIGHT)), p + (w * h));
 }
 
 } // End of namespace Access
diff --git a/engines/access/room.cpp b/engines/access/room.cpp
index 37746d1b7c..f32bc95ae0 100644
--- a/engines/access/room.cpp
+++ b/engines/access/room.cpp
@@ -339,7 +339,27 @@ void Room::buildColumn(int playX, int screenX) {
 }
 
 void Room::buildRow(int playY, int screenY) {
-	error("TODO: buildRow");
+	if (playY < 0 || playY >= _playFieldHeight)
+		return;
+	assert(screenY <= (_vm->_screen->h - TILE_HEIGHT));
+
+	const byte *pSrc = _playField + screenY *_playFieldWidth + _vm->_screen->_scrollCol;
+
+	// WORKAROUND: Original's use of '+ 1' would frequently cause memory overruns
+	int w = MIN(_vm->_screen->_vWindowWidth + 1, _playFieldWidth);
+
+	for (int x = 0; x < w; ++x) {
+		byte *pTile = _tile + (*pSrc << 8);
+		byte *pDest = (byte *)_vm->_buffer1.getBasePtr(w * TILE_WIDTH, screenY);
+
+		for (int tileY = 0; tileY < TILE_HEIGHT; ++tileY) {
+			Common::copy(pTile, pTile + TILE_WIDTH, pDest);
+			pTile += TILE_WIDTH;
+			pDest += _vm->_buffer1.pitch;
+		}
+
+		++pSrc;
+	}
 }
 
 void Room::loadPlayField(int fileNum, int subfile) {