diff --git a/newgrf.c b/newgrf.c
index 0cd835ac2f..dc5a55210f 100644
--- a/newgrf.c
+++ b/newgrf.c
@@ -862,9 +862,9 @@ static bool StationChangeInfo(uint stid, int numinfo, int prop, byte **bufp, int
 						if ((byte) dtss->delta_x == 0x80) break;
 						dtss->delta_y = grf_load_byte(&buf);
 						dtss->delta_z = grf_load_byte(&buf);
-						dtss->width = grf_load_byte(&buf);
-						dtss->height = grf_load_byte(&buf);
-						dtss->unk = grf_load_byte(&buf);
+						dtss->size_x = grf_load_byte(&buf);
+						dtss->size_y = grf_load_byte(&buf);
+						dtss->size_z = grf_load_byte(&buf);
 						dtss->image = grf_load_dword(&buf);
 
 						/* Remap flags as ours collide */
diff --git a/rail_cmd.c b/rail_cmd.c
index fc05800e45..1dd401df6a 100644
--- a/rail_cmd.c
+++ b/rail_cmd.c
@@ -1382,8 +1382,8 @@ default_waypoint:
 			AddSortableSpriteToDraw(
 				image,
 				ti->x + dtss->delta_x, ti->y + dtss->delta_y,
-				dtss->width, dtss->height,
-				dtss->unk, ti->z + dtss->delta_z
+				dtss->size_x, dtss->size_y,
+				dtss->size_z, ti->z + dtss->delta_z
 			);
 		}
 	}
diff --git a/sprite.h b/sprite.h
index 21a9f32cf0..9dca01a668 100644
--- a/sprite.h
+++ b/sprite.h
@@ -12,8 +12,9 @@ typedef struct DrawTileSeqStruct {
 	int8 delta_x; // 0x80 is sequence terminator
 	int8 delta_y;
 	int8 delta_z;
-	byte width,height;
-	byte unk; // 'depth', just z-size; TODO: rename
+	byte size_x;
+	byte size_y;
+	byte size_z;
 	uint32 image;
 } DrawTileSeqStruct;
 
diff --git a/station_cmd.c b/station_cmd.c
index 4433b518f6..1e8a4ea12b 100644
--- a/station_cmd.c
+++ b/station_cmd.c
@@ -2119,7 +2119,12 @@ static void DrawTile_Station(TileInfo *ti)
 		}
 
 		if ((byte)dtss->delta_z != 0x80) {
-			AddSortableSpriteToDraw(image, ti->x + dtss->delta_x, ti->y + dtss->delta_y, dtss->width, dtss->height, dtss->unk, ti->z + dtss->delta_z);
+			AddSortableSpriteToDraw(
+				image,
+				ti->x + dtss->delta_x, ti->y + dtss->delta_y,
+				dtss->size_x, dtss->size_y,
+				dtss->size_z, ti->z + dtss->delta_z
+			);
 		} else {
 			AddChildSpriteScreen(image, dtss->delta_x, dtss->delta_y);
 		}
diff --git a/unmovable_cmd.c b/unmovable_cmd.c
index 306a9b447c..7da8360418 100644
--- a/unmovable_cmd.c
+++ b/unmovable_cmd.c
@@ -165,8 +165,10 @@ static void DrawTile_Unmovable(TileInfo *ti)
 					image |= ormod;
 				}
 				AddSortableSpriteToDraw(
-					image, ti->x + dtss->delta_x, ti->y + dtss->delta_y,
-					dtss->width, dtss->height, dtss->unk, ti->z + dtss->delta_z
+					image,
+					ti->x + dtss->delta_x, ti->y + dtss->delta_y,
+					dtss->size_x, dtss->size_y,
+					dtss->size_z, ti->z + dtss->delta_z
 				);
 			}
 			break;