diff --git a/src/windows/track_place.c b/src/windows/track_place.c
index 1023196bae..eb1b933d26 100644
--- a/src/windows/track_place.c
+++ b/src/windows/track_place.c
@@ -304,14 +304,69 @@ static void window_track_place_draw_mini_preview()
  *
  *  rct2: 0x0068A15E
  */
-static void sub_68A15E(int x, int y, short *ax, short *bx)
+static void sub_68A15E(int screenX, int screenY, int *x, int *y, int *direction, rct_map_element **mapElement)
 {
-	int eax, ebx, ecx, edx, esi, edi, ebp;
-	eax = x;
-	ebx = y;
-	RCT2_CALLFUNC_X(0x0068A15E, &eax, &ebx, &ecx, &edx, &esi, &edi, &ebp);
-	*ax = *((short*)&eax);
-	*bx = *((short*)&ebx);
+	int z;
+	rct_map_element *myMapElement;
+	rct_viewport *viewport;
+	get_map_coordinates_from_pos(screenX, screenY, 0xFFF6, x, y, &z, &myMapElement, &viewport);
+
+	if (z == 0) {
+		*x = 0x8000;
+		return;
+	}
+
+	RCT2_GLOBAL(0x00F1AD3E, uint8) = z;
+	RCT2_GLOBAL(0x00F1AD30, rct_map_element*) = myMapElement;
+
+	if (z == 4) {
+		// myMapElement appears to be water
+		z = myMapElement->properties.surface.terrain;
+		z = (z & MAP_ELEMENT_WATER_HEIGHT_MASK) << 4;
+	}
+
+	RCT2_GLOBAL(0x00F1AD3C, uint16) = z;
+	RCT2_GLOBAL(0x00F1AD34, uint16) = *x;
+	RCT2_GLOBAL(0x00F1AD36, uint16) = *y;
+	RCT2_GLOBAL(0x00F1AD38, uint16) = *x + 31;
+	RCT2_GLOBAL(0x00F1AD3A, uint16) = *y + 31;
+
+	rct_xy16 start_vp_pos = screen_coord_to_viewport_coord(viewport, screenX, screenY);
+	rct_xy16 map_pos = { *x + 16, *y + 16 };
+
+	for (int i = 0; i < 5; i++) {
+		if (RCT2_GLOBAL(0x00F1AD3E, uint8) != 4) {
+			z = map_element_height(map_pos.x, map_pos.y);
+		} else {
+			z = RCT2_GLOBAL(0x00F1AD3C, uint16);
+		}
+		map_pos = viewport_coord_to_map_coord(start_vp_pos.x, start_vp_pos.y, z);
+		map_pos.x = clamp(RCT2_GLOBAL(0x00F1AD34, uint16), map_pos.x, RCT2_GLOBAL(0x00F1AD38, uint16));
+		map_pos.y = clamp(RCT2_GLOBAL(0x00F1AD36, uint16), map_pos.y, RCT2_GLOBAL(0x00F1AD3A, uint16));
+	}
+
+	// Determine to which edge the cursor is closest
+	int myDirection;
+	int mod_x = map_pos.x & 0x1F;
+	int mod_y = map_pos.y & 0x1F;
+	if (mod_x < mod_y) {
+		if (mod_x + mod_y < 32) {
+			myDirection = 0;
+		} else {
+			myDirection = 1;
+		}
+	} else {
+		if (mod_x + mod_y < 32) {
+			myDirection = 3;
+		} else {
+			myDirection = 2;
+		}
+	}
+
+	*x = map_pos.x & ~0x1F;
+	*y = map_pos.y & ~0x1F;
+	if (direction != NULL) *direction = myDirection;
+	if (mapElement != NULL) *mapElement = myMapElement;
 }
 
 /**
@@ -483,7 +538,7 @@ static void window_track_place_toolupdate()
 	RCT2_GLOBAL(RCT2_ADDRESS_MAP_SELECTION_FLAGS, uint16) &= ~7;
 
 	// Get the tool map position
-	sub_68A15E(x, y, &x, &y);
+	sub_68A15E(x, y, &x, &y, NULL, NULL);
 	if (x == (short)0x8000) {
 		window_track_place_clear_provisional();
 		return;
@@ -545,7 +600,7 @@ static void window_track_place_tooldown()
 	map_invalidate_map_selection_tiles();
 	RCT2_GLOBAL(RCT2_ADDRESS_MAP_SELECTION_FLAGS, uint16) &= ~7;
 
-	sub_68A15E(x, y, &x, &y);
+	sub_68A15E(x, y, &x, &y, NULL, NULL);
 	if (x == (short)0x8000)
 		return;