diff --git a/src/drawing/drawing.c b/src/drawing/drawing.c
index 888b4e43cb..cb75ded2b0 100644
--- a/src/drawing/drawing.c
+++ b/src/drawing/drawing.c
@@ -178,74 +178,6 @@ void load_palette(){
 	platform_update_palette((char*)0x01424680, 10, 236);
 }
 
-/**
-*
-*  rct2: 0x006EC9CE
-* @param x (ax)
-* @param y (cx)
-* @param base_height (di)
-* @param clearance_height (si)
-*/
-void gfx_invalidate_tile_if_zoomed(int x, int y, int base_height, int clearance_height)
-{
-	x += 16;
-	y += 16;
-	int left, top, right, bottom;
-	switch (RCT2_GLOBAL(RCT2_ADDRESS_CURRENT_ROTATION, uint32)) {
-		case 0:
-			left = (-x + y) - 32;
-			right = (-x + y) + 32;
-			top = ((y + x) / 2) - 32 - clearance_height;
-			bottom = ((y + x) / 2) + 32 - base_height;
-			break;
-		case 1:
-			left = (-x - y) - 32;
-			right = (-x - y) + 32;
-			top = ((y - x) / 2) - 32 - clearance_height;
-			bottom = ((y - x) / 2) + 32 - base_height;
-			break;
-		case 2:
-			left = (x - y) - 32;
-			right = (x - y) + 32;
-			top = ((-y - x) / 2) - 32 - clearance_height;
-			bottom = ((-y - x) / 2) + 32 - base_height;
-			break;
-		case 3:
-			left = (x + y) - 32;
-			right = (x + y) + 32;
-			top = ((-y + x) / 2) - 32 - clearance_height;
-			bottom = ((-y + x) / 2) + 32 - base_height;
-			break;
-	}
-	for (rct_viewport** viewport_p = RCT2_ADDRESS(RCT2_ADDRESS_ACTIVE_VIEWPORT_PTR_ARRAY, rct_viewport*); *viewport_p; ++viewport_p)
-	{
-		rct_viewport* viewport = *viewport_p;
-		if (viewport->zoom < 1) {
-			if (right > viewport->view_x && bottom > viewport->view_y && left < viewport->view_x + viewport->view_width) {
-				if (left < viewport->view_x) {
-					left = viewport->view_x;
-				}
-				if (right > viewport->view_x + viewport->view_width) {
-					right = viewport->view_x + viewport->view_width;
-				}
-				if (top < viewport->view_y + viewport->view_height) {
-					if (top < viewport->view_y) {
-						top = viewport->view_y;
-					}
-					if (bottom > viewport->view_y + viewport->view_height) {
-						bottom = viewport->view_y + viewport->view_height;
-					}
-					left = ((left - viewport->view_x) >> viewport->zoom) + viewport->x;
-					top = ((top - viewport->view_y) >> viewport->zoom) + viewport->y;
-					right = ((right - viewport->view_x) >> viewport->zoom) + viewport->x;
-					bottom = ((bottom - viewport->view_y) >> viewport->zoom) + viewport->y;
-					gfx_set_dirty_blocks(left, top, right, bottom);
-				}
-			}
-		}
-	}
-}
-
 /**
  *
  *  rct2: 0x006ED7E5
diff --git a/src/drawing/drawing.h b/src/drawing/drawing.h
index 4e061cd5f8..a6269c8f01 100644
--- a/src/drawing/drawing.h
+++ b/src/drawing/drawing.h
@@ -83,7 +83,6 @@ rct_drawpixelinfo* clip_drawpixelinfo(rct_drawpixelinfo* dpi, int left, int widt
 void gfx_set_dirty_blocks(uint16 left, uint16 top, uint16 right, uint16 bottom);
 void gfx_draw_all_dirty_blocks();
 void gfx_redraw_screen_rect(short left, short top, short right, short bottom);
-void gfx_invalidate_tile_if_zoomed(int x, int y, int base_height, int clearance_height);
 void gfx_invalidate_screen();
 
 // palette
diff --git a/src/interface/viewport.c b/src/interface/viewport.c
index 71d6c5206a..c3bcf35d45 100644
--- a/src/interface/viewport.c
+++ b/src/interface/viewport.c
@@ -2471,4 +2471,36 @@ void get_map_coordinates_from_pos(int screenX, int screenY, int flags, sint16 *x
 	if (x != NULL) *x = RCT2_GLOBAL(0x9AC14C, int16_t);
 	if (y != NULL) *y = RCT2_GLOBAL(0x9AC14E, int16_t);
 	if (mapElement != NULL) *mapElement = RCT2_GLOBAL(0x9AC150, rct_map_element*);
-}
\ No newline at end of file
+}
+
+/**
+ * Left, top, right and bottom represent 2D map coordinates at zoom 0.
+ */
+void viewport_invalidate(rct_viewport *viewport, int left, int top, int right, int bottom)
+{
+	int viewportLeft = viewport->view_x;
+	int viewportTop = viewport->view_y;
+	int viewportRight = viewport->view_x + viewport->view_width;
+	int viewportBottom = viewport->view_y + viewport->view_height;
+	if (right > viewportLeft && bottom > viewportTop) {
+		left = max(left, viewportLeft);
+		top = max(top, viewportTop);
+		right = min(right, viewportRight);
+		bottom = min(bottom, viewportBottom);
+
+		uint8 zoom = 1 << viewport->zoom;
+		left -= viewportLeft;
+		top -= viewportTop;
+		right -= viewportLeft;
+		bottom -= viewportTop;
+		left /= zoom;
+		top /= zoom;
+		right /= zoom;
+		bottom /= zoom;
+		left += viewport->x;
+		top += viewport->y;
+		right += viewport->x;
+		bottom += viewport->y;
+		gfx_set_dirty_blocks(left, top, right, bottom);
+	}
+}
diff --git a/src/interface/viewport.h b/src/interface/viewport.h
index 62cfa47c7f..6cbcd5b264 100644
--- a/src/interface/viewport.h
+++ b/src/interface/viewport.h
@@ -130,4 +130,6 @@ void sub_0x68615B(int ebp);
 void sub_688485();
 void sub_688217();
 
+void viewport_invalidate(rct_viewport *viewport, int left, int top, int right, int bottom);
+
 #endif
diff --git a/src/peep/peep.c b/src/peep/peep.c
index 1c55217281..7b1557767d 100644
--- a/src/peep/peep.c
+++ b/src/peep/peep.c
@@ -2777,7 +2777,7 @@ static void peep_update_mowing(rct_peep* peep){
 
 		if ((map_element->properties.surface.terrain & MAP_ELEMENT_SURFACE_TERRAIN_MASK) == (TERRAIN_GRASS << 5)){
 			map_element->properties.surface.grass_length = 0;
-			gfx_invalidate_tile_if_zoomed(peep->next_x, peep->next_y, map_element->base_height * 8, map_element->base_height * 8 + 16);
+			map_invalidate_tile_zoom0(peep->next_x, peep->next_y, map_element->base_height * 8, map_element->base_height * 8 + 16);
 		}
 		peep->staff_lawns_mown++;
 		peep->var_45 |= (1 << 5);
@@ -2827,7 +2827,7 @@ static void peep_update_watering(rct_peep* peep){
 				continue;
 			
 			map_element->properties.scenery.age = 0;
-			gfx_invalidate_tile_if_zoomed(x, y, map_element->base_height * 8, map_element->clearance_height * 8);
+			map_invalidate_tile_zoom0(x, y, map_element->base_height * 8, map_element->clearance_height * 8);
 			peep->staff_gardens_watered++;
 			peep->var_45 |= (1 << 4);	
 		} while (!map_element_is_last_for_tile(map_element++));
@@ -2897,7 +2897,7 @@ static void peep_update_emptying_bin(rct_peep* peep){
 
 		map_element->properties.path.addition_status |= ((3 << peep->var_37) << peep->var_37);
 
-		gfx_invalidate_tile_if_zoomed(peep->next_x, peep->next_y, map_element->base_height * 8, map_element->clearance_height * 8);
+		map_invalidate_tile_zoom0(peep->next_x, peep->next_y, map_element->base_height * 8, map_element->clearance_height * 8);
 
 		peep->staff_bins_emptied++;
 		peep->var_45 |= (1 << 4);
@@ -3316,7 +3316,7 @@ static void peep_update_walking_break_scenery(rct_peep* peep){
 
 	map_element->flags |= MAP_ELEMENT_FLAG_BROKEN;
 
-	map_invalidate_tile(
+	map_invalidate_tile_zoom1(
 		peep->next_x, 
 		peep->next_y, 
 		(map_element->base_height << 3) + 32, 
@@ -3541,7 +3541,7 @@ static void peep_update_using_bin(rct_peep* peep){
 		// Then placeing the new value.
 		map_element->properties.path.addition_status |= rubbish_in_bin << selected_bin;
 
-		gfx_invalidate_tile_if_zoomed(peep->next_x, peep->next_y, map_element->base_height << 3, map_element->clearance_height << 3);
+		map_invalidate_tile_zoom0(peep->next_x, peep->next_y, map_element->base_height << 3, map_element->clearance_height << 3);
 		peep_state_reset(peep);
 	}
 }
diff --git a/src/ride/ride.c b/src/ride/ride.c
index c1a2538c99..67fcaee246 100644
--- a/src/ride/ride.c
+++ b/src/ride/ride.c
@@ -1756,12 +1756,12 @@ static void ride_chairlift_update(rct_ride *ride)
 	x = (ride->var_13A & 0xFF) * 32;
 	y = (ride->var_13A >> 8) * 32;
 	z = ride->var_13E * 8;
-	map_invalidate_tile(x, y, z, z + (4 * 8));
+	map_invalidate_tile_zoom1(x, y, z, z + (4 * 8));
 
 	x = (ride->var_13C & 0xFF) * 32;
 	y = (ride->var_13C >> 8) * 32;
 	z = ride->var_13F * 8;
-	map_invalidate_tile(x, y, z, z + (4 * 8));
+	map_invalidate_tile_zoom1(x, y, z, z + (4 * 8));
 }
 
 /**
@@ -1837,7 +1837,7 @@ static void ride_spiral_slide_update(rct_ride *ride)
 		x += RCT2_GLOBAL(0x0098DDB8 + (rotation * 4), sint16);
 		y += RCT2_GLOBAL(0x0098DDBA + (rotation * 4), sint16);
 
-		gfx_invalidate_tile_if_zoomed(x, y, mapElement->base_height * 8, mapElement->clearance_height * 8);
+		map_invalidate_tile_zoom0(x, y, mapElement->base_height * 8, mapElement->clearance_height * 8);
 	}
 }
 
diff --git a/src/ride/station.c b/src/ride/station.c
index c982a44757..9dffe1680a 100644
--- a/src/ride/station.c
+++ b/src/ride/station.c
@@ -300,7 +300,7 @@ static void ride_invalidate_station_start(rct_ride *ride, int stationIndex, int
 		mapElement->properties.track.sequence |= 0x80;
 
 	// Invalidate map tile
-	map_invalidate_tile(x, y, mapElement->base_height * 8, mapElement->clearance_height * 8);
+	map_invalidate_tile_zoom1(x, y, mapElement->base_height * 8, mapElement->clearance_height * 8);
 }
 
 rct_map_element *ride_get_station_start_track_element(rct_ride *ride, int stationIndex)
diff --git a/src/windows/sign.c b/src/windows/sign.c
index 1c92097184..7c9cc5ed9e 100644
--- a/src/windows/sign.c
+++ b/src/windows/sign.c
@@ -623,7 +623,7 @@ static void window_sign_small_dropdown()
 		((w->var_492 & 0x7) << 5);
 	map_element->flags |= ((w->var_492 & 0x18) << 2);
 
-	gfx_invalidate_viewport_tile(x, y, map_element->base_height * 8, map_element->clearance_height * 8);
+	map_invalidate_tile(x, y, map_element->base_height * 8, map_element->clearance_height * 8);
 	window_invalidate(w);
 }
 
diff --git a/src/world/map.c b/src/world/map.c
index 826df6347e..381a568992 100644
--- a/src/world/map.c
+++ b/src/world/map.c
@@ -66,9 +66,11 @@ static void map_update_grass_length(int x, int y, rct_map_element *mapElement);
 static void map_set_grass_length(int x, int y, rct_map_element *mapElement, int length);
 static void sub_68AE2A(int x, int y);
 
-void rotate_map_coordinates(sint16* x, sint16* y, int rotation){
+void rotate_map_coordinates(sint16 *x, sint16 *y, int rotation)
+{
 	int temp;
-	switch (rotation){
+
+	switch (rotation) {
 	case MAP_ELEMENT_DIRECTION_WEST:
 		break;
 	case MAP_ELEMENT_DIRECTION_NORTH:
@@ -660,16 +662,6 @@ int map_is_location_in_park(int x, int y)
 	return 0;
 }
 
-/**
- *
- *  rct2: 0x006ECB60
- * NOTE: x, y and z are in pixels, not tile units
- */
-void map_invalidate_tile(int x, int y, int zLow, int zHigh)
-{
-	RCT2_CALLPROC_X(0x006ECB60, x, 0, y, 0, zHigh, zLow, 0);
-}
-
 /**
  *
  *  rct2: 0x006E0E01
@@ -897,7 +889,7 @@ void game_command_remove_banner(int* eax, int* ebx, int* ecx, int* edx, int* esi
 	uint8 bannerType = banner->type;
 	if (*ebx & GAME_COMMAND_FLAG_APPLY) {
 		map_element_remove_banner_entry(map_element);
-		map_invalidate_tile(x, y, z, z + 32);
+		map_invalidate_tile_zoom1(x, y, z, z + 32);
 		map_element_remove(map_element);
 	}
 	rct_scenery_entry *scenery_entry = (rct_scenery_entry*)object_entry_groups[OBJECT_TYPE_BANNERS].chunks[bannerType];
@@ -1003,7 +995,7 @@ void game_command_set_fence_colour(int* eax, int* ebx, int* ecx, int* edx, int*
 			if(scenery_entry->wall.flags & 0x80){
 				map_element->properties.fence.item[0] = color3;
 			}
-			map_invalidate_tile(x, y, z, z + 0x48);
+			map_invalidate_tile_zoom1(x, y, z, z + 0x48);
 		}
 		*ebx = 0;
 	} else {
@@ -1167,7 +1159,7 @@ void game_command_set_banner_colour(int* eax, int* ebx, int* ecx, int* edx, int*
 			window_invalidate(window);
 		}
 		gBanners[map_element->properties.banner.index].colour = color;
-		map_invalidate_tile(x, y, z, z + 32);
+		map_invalidate_tile_zoom1(x, y, z, z + 32);
 	}
 	
 	*ebx = 0;
@@ -1953,7 +1945,7 @@ void game_command_remove_fence(int* eax, int* ebx, int* ecx, int* edx, int* esi,
 	}
 
 	map_element_remove_banner_entry(map_element);
-	map_invalidate_tile(x, y, map_element->base_height * 8, (map_element->base_height * 8) + 72);
+	map_invalidate_tile_zoom1(x, y, map_element->base_height * 8, (map_element->base_height * 8) + 72);
 	map_element_remove(map_element);
 	*ebx = 0;
 }
@@ -2478,7 +2470,7 @@ void game_command_place_fence(int* eax, int* ebx, int* ecx, int* edx, int* esi,
 		}
 
 		RCT2_GLOBAL(0x00F64EBC, rct_map_element*) = map_element;
-		map_invalidate_tile(position.x, position.y, map_element->base_height * 8, map_element->base_height * 8 + 72);
+		map_invalidate_tile_zoom1(position.x, position.y, map_element->base_height * 8, map_element->base_height * 8 + 72);
 	}
 
 	if (RCT2_GLOBAL(RCT2_ADDRESS_PARK_FLAGS, uint32) & PARK_FLAGS_NO_MONEY){
@@ -2706,15 +2698,6 @@ void game_command_place_large_scenery(int* eax, int* ebx, int* ecx, int* edx, in
 	*ebx = MONEY32_UNDEFINED;
 }
 
-/**
- *
- *  rct2: 0x006EC6D7
- */
-void map_invalidate_tile_full(int x, int y)
-{
-	RCT2_CALLPROC_X(0x006EC6D7, x, 0, y, 0, 0, 0, 0);
-}
-
 int map_get_station(rct_map_element *mapElement)
 {
 	return (mapElement->properties.track.sequence & 0x70) >> 4;
@@ -2975,7 +2958,7 @@ void map_remove_intersecting_walls(int x, int y, int z0, int z1, int direction)
 			continue;
 
 		map_element_remove_banner_entry(mapElement);
-		map_invalidate_tile(x, y, mapElement->base_height * 8, mapElement->base_height * 8 + 72);
+		map_invalidate_tile_zoom1(x, y, mapElement->base_height * 8, mapElement->base_height * 8 + 72);
 		map_element_remove(mapElement);
 		mapElement--;
 	} while (!map_element_is_last_for_tile(mapElement++));
@@ -3084,7 +3067,7 @@ static void map_set_grass_length(int x, int y, rct_map_element *mapElement, int
 	mapElement->properties.surface.grass_length = length;
 	z0 = mapElement->base_height * 8;
 	z1 = z0 + 16;
-	gfx_invalidate_viewport_tile(x, y, z0, z1);
+	map_invalidate_tile(x, y, z0, z1);
 }
 
 void sub_6A7594()
@@ -3334,32 +3317,6 @@ bool map_element_is_underground(rct_map_element *mapElement)
 	return true;
 }
 
-void map_rotate_position(int direction, int *x, int *y)
-{
-	int offsetX, offsetY;
-
-	switch (direction) {
-	case 0:
-		offsetX = (*x);
-		offsetY = (*y);
-		break;
-	case 1:
-		offsetX = (*y);
-		offsetY = -(*x);
-		break;
-	case 2:
-		offsetX = -(*x);
-		offsetY = -(*y);
-		break;
-	case 3:
-		offsetX = -(*y);
-		offsetY = (*x);
-		break;
-	}
-	*x = offsetX;
-	*y = offsetY;
-}
-
 rct_map_element *map_get_large_scenery_segment(int x, int y, int z, int direction, int sequence)
 {
 	rct_map_element *mapElement = map_get_first_element_at(x >> 5, y >> 5);
@@ -3385,7 +3342,7 @@ bool map_large_scenery_get_origin(
 	rct_map_element *mapElement;
 	rct_scenery_entry *sceneryEntry;
 	rct_large_scenery_tile *tile;
-	int offsetX, offsetY;
+	sint16 offsetX, offsetY;
 
 	mapElement = map_get_large_scenery_segment(x, y, z, direction, sequence);
 	if (mapElement == NULL)
@@ -3396,7 +3353,7 @@ bool map_large_scenery_get_origin(
 
 	offsetX = tile->x_offset;
 	offsetY = tile->y_offset;
-	map_rotate_position(direction, &offsetX, &offsetY);
+	rotate_map_coordinates(&offsetX, &offsetY, direction);
 
 	*outX = x - offsetX;
 	*outY = y - offsetY;
@@ -3410,12 +3367,11 @@ bool map_large_scenery_get_origin(
  */
 void sign_set_colour(int x, int y, int z, int direction, int sequence, uint8 mainColour, uint8 textColour)
 {
-	// RCT2_CALLPROC_X(0x006B9B05, x, direction << 8, y, z | (type << 8), 0, 0, 0);
-
 	rct_map_element *mapElement;
 	rct_scenery_entry *sceneryEntry;
 	rct_large_scenery_tile *sceneryTiles, *tile;
-	int x0, y0, z0, offsetX, offsetY;
+	sint16 offsetX, offsetY;
+	int x0, y0, z0;
 
 	// Get the given segment of the large scenery element
 	mapElement = map_get_large_scenery_segment(x, y, z, direction, sequence);
@@ -3428,7 +3384,7 @@ void sign_set_colour(int x, int y, int z, int direction, int sequence, uint8 mai
 	tile = &sceneryTiles[sequence];
 	offsetX = tile->x_offset;
 	offsetY = tile->y_offset;
-	map_rotate_position(direction, &offsetX, &offsetY);
+	rotate_map_coordinates(&offsetX, &offsetY, direction);
 	x0 = x - offsetX;
 	y0 = y - offsetY;
 	z0 = (z * 8) - tile->z_offset;
@@ -3438,7 +3394,7 @@ void sign_set_colour(int x, int y, int z, int direction, int sequence, uint8 mai
 	for (tile = sceneryTiles; tile->x_offset != -1; tile++, sequence++) {
 		offsetX = tile->x_offset;
 		offsetY = tile->y_offset;
-		map_rotate_position(direction, &offsetX, &offsetY);
+		rotate_map_coordinates(&offsetX, &offsetY, direction);
 
 		x = x0 + offsetX;
 		y = y0 + offsetY;
@@ -3450,7 +3406,94 @@ void sign_set_colour(int x, int y, int z, int direction, int sequence, uint8 mai
 			mapElement->properties.scenerymultiple.colour[0] |= mainColour;
 			mapElement->properties.scenerymultiple.colour[1] |= textColour;
 
-			gfx_invalidate_viewport_tile(x, y, mapElement->base_height * 8 , mapElement->clearance_height * 8);
+			map_invalidate_tile(x, y, mapElement->base_height * 8 , mapElement->clearance_height * 8);
 		}
 	}
 }
+
+static void translate_3d_to_2d(int rotation, int *x, int *y)
+{
+	int rx, ry;
+
+	switch (rotation & 3) {
+	case 0:
+		rx = (*y) - (*x);
+		ry = (*x) + (*y);
+		break;
+	case 1:
+		rx = -(*x) - (*y);
+		ry = (*y) - (*x);
+		break;
+	case 2:
+		rx = (*x) - (*y);
+		ry = -(*x) - (*y);
+		break;
+	case 3:
+		rx = (*x) + (*y);
+		ry = (*x) - (*y);
+		break;
+	}
+	ry /= 2;
+
+	*x = rx;
+	*y = ry;
+}
+
+void map_invalidate_tile_under_zoom(int x, int y, int z0, int z1, int maxZoom)
+{
+	int x1, y1, x2, y2;
+	rct_viewport *viewport;
+
+	x += 16;
+	y += 16;
+	translate_3d_to_2d(RCT2_GLOBAL(RCT2_ADDRESS_CURRENT_ROTATION, uint32), &x, &y);
+
+	x1 = x - 32;
+	y1 = y - 32 - z1;
+	x2 = x + 32;
+	y2 = y + 32 - z0;
+
+	viewport = RCT2_GLOBAL(RCT2_ADDRESS_ACTIVE_VIEWPORT_PTR_ARRAY, rct_viewport*);
+	while (viewport->width != 0) {
+		if (maxZoom == -1 || viewport->zoom <= maxZoom) {
+			viewport_invalidate(viewport, x1, y1, x2, y2);
+		}
+		viewport++;
+	}
+}
+
+/**
+ *
+ *  rct2: 0x006EC847
+ */
+void map_invalidate_tile(int x, int y, int z0, int z1)
+{
+	map_invalidate_tile_under_zoom(x, y, z0, z1, -1);
+}
+
+/**
+ *
+ *  rct2: 0x006ECB60
+ */
+void map_invalidate_tile_zoom1(int x, int y, int z0, int z1)
+{
+	map_invalidate_tile_under_zoom(x, y, z0, z1, 1);
+}
+
+/**
+ *
+ *  rct2: 0x006EC9CE
+ */
+void map_invalidate_tile_zoom0(int x, int y, int z0, int z1)
+{
+	map_invalidate_tile_under_zoom(x, y, z0, z1, 0);
+}
+
+/**
+ *
+ *  rct2: 0x006EC6D7
+ */
+void map_invalidate_tile_full(int x, int y)
+{
+	map_invalidate_tile(x, y, 0, 2080);
+}
diff --git a/src/world/map.h b/src/world/map.h
index f3e6399f10..ae2477c493 100644
--- a/src/world/map.h
+++ b/src/world/map.h
@@ -276,8 +276,6 @@ int map_coord_is_connected(int x, int y, int z, uint8 faceDirection);
 void sub_6A876D();
 int map_is_location_owned(int x, int y, int z);
 int map_is_location_in_park(int x, int y);
-void map_invalidate_tile(int x, int y, int zLow, int zHigh);
-void map_invalidate_tile_full(int x, int y);
 int map_get_station(rct_map_element *mapElement);
 void map_element_remove(rct_map_element *mapElement);
 void sub_6A6AA7(int x, int y, rct_map_element *mapElement);
@@ -289,7 +287,7 @@ int sub_68B044();
 rct_map_element *map_element_insert(int x, int y, int z, int flags);
 int map_can_construct_with_clear_at(int x, int y, int zLow, int zHigh, void *clearFunc, uint8 bl);
 int map_can_construct_at(int x, int y, int zLow, int zHigh, uint8 bl);
-void rotate_map_coordinates(sint16* x, sint16* y, int rotation);
+void rotate_map_coordinates(sint16 *x, sint16 *y, int rotation);
 rct_xy16 coordinate_3d_to_2d(const rct_xyz16* coordinate_3d, int rotation);
 money32 map_clear_scenery(int x0, int y0, int x1, int y1, int flags);
 money32 lower_water(sint16 x0, sint16 y0, sint16 x1, sint16 y1, uint8 flags);
@@ -343,4 +341,9 @@ void map_extend_boundary_surface();
 
 void sign_set_colour(int x, int y, int z, int direction, int sequence, uint8 mainColour, uint8 textColour);
 
+void map_invalidate_tile(int x, int y, int z0, int z1);
+void map_invalidate_tile_zoom1(int x, int y, int z0, int z1);
+void map_invalidate_tile_zoom0(int x, int y, int z0, int z1);
+void map_invalidate_tile_full(int x, int y);
+
 #endif
diff --git a/src/world/map_animation.c b/src/world/map_animation.c
index 62f879448d..e612e07ed8 100644
--- a/src/world/map_animation.c
+++ b/src/world/map_animation.c
@@ -124,7 +124,7 @@ static bool map_animation_invalidate_ride_entrance(int x, int y, int baseZ)
 		entranceDefinition = &RideEntranceDefinitions[ride->entrance_style];
 
 		int height = (mapElement->base_height * 8) + entranceDefinition->height + 8;
-		map_invalidate_tile(x, y, height, height + 16);
+		map_invalidate_tile_zoom1(x, y, height, height + 16);
 		return false;
 	} while (!map_element_is_last_for_tile(mapElement++));
 
@@ -153,7 +153,7 @@ static bool map_animation_invalidate_queue_banner(int x, int y, int baseZ)
 		int direction = ((mapElement->type >> 6) + RCT2_GLOBAL(RCT2_ADDRESS_CURRENT_ROTATION, uint8)) & 3;
 		if (direction == MAP_ELEMENT_DIRECTION_NORTH || direction == MAP_ELEMENT_DIRECTION_EAST) {
 			baseZ = mapElement->base_height * 8;
-			map_invalidate_tile(x, y, baseZ + 16, baseZ + 30);
+			map_invalidate_tile_zoom1(x, y, baseZ + 16, baseZ + 30);
 		}
 		return false;
 	} while (!map_element_is_last_for_tile(mapElement++));
@@ -183,7 +183,7 @@ static bool map_animation_invalidate_small_scenery(int x, int y, int baseZ)
 
 		sceneryEntry = g_smallSceneryEntries[mapElement->properties.scenery.type];
 		if (sceneryEntry->small_scenery.flags & 0xD800) {
-			map_invalidate_tile(x, y, mapElement->base_height * 8, mapElement->clearance_height * 8);
+			map_invalidate_tile_zoom1(x, y, mapElement->base_height * 8, mapElement->clearance_height * 8);
 			return false;
 		}
 
@@ -216,7 +216,7 @@ static bool map_animation_invalidate_small_scenery(int x, int y, int baseZ)
 					break;
 				}
 			}
-			map_invalidate_tile(x, y, mapElement->base_height * 8, mapElement->clearance_height * 8);
+			map_invalidate_tile_zoom1(x, y, mapElement->base_height * 8, mapElement->clearance_height * 8);
 			return false;
 		}
 	} while (!map_element_is_last_for_tile(mapElement++));
@@ -243,7 +243,7 @@ static bool map_animation_invalidate_park_entrance(int x, int y, int baseZ)
 			continue;
 
 		baseZ = mapElement->base_height * 8;
-		map_invalidate_tile(x, y, baseZ + 32, baseZ + 64);
+		map_invalidate_tile_zoom1(x, y, baseZ + 32, baseZ + 64);
 		return false;
 	} while (!map_element_is_last_for_tile(mapElement++));
 
@@ -267,7 +267,7 @@ static bool map_animation_invalidate_track_waterfall(int x, int y, int baseZ)
 
 		if (mapElement->properties.track.type == TRACK_ELEM_WATERFALL) {
 			int z = mapElement->base_height * 8;
-			map_invalidate_tile(x, y, z + 14, z + 46);
+			map_invalidate_tile_zoom1(x, y, z + 14, z + 46);
 			return false;
 		}
 	} while (!map_element_is_last_for_tile(mapElement++));
@@ -292,7 +292,7 @@ static bool map_animation_invalidate_track_rapids(int x, int y, int baseZ)
 
 		if (mapElement->properties.track.type == TRACK_ELEM_RAPIDS) {
 			int z = mapElement->base_height * 8;
-			map_invalidate_tile(x, y, z + 14, z + 18);
+			map_invalidate_tile_zoom1(x, y, z + 14, z + 18);
 			return false;
 		}
 	} while (!map_element_is_last_for_tile(mapElement++));
@@ -318,7 +318,7 @@ static bool map_animation_invalidate_track_onridephoto(int x, int y, int baseZ)
 
 		if (mapElement->properties.track.type == TRACK_ELEM_ON_RIDE_PHOTO) {
 			int z = mapElement->base_height * 8;
-			map_invalidate_tile(x, y, mapElement->base_height * 8, mapElement->clearance_height * 8);
+			map_invalidate_tile_zoom1(x, y, mapElement->base_height * 8, mapElement->clearance_height * 8);
 			if (mapElement->properties.track.sequence & 0xF0) {
 				mapElement->properties.track.sequence -= 0x10;
 				return false;
@@ -348,7 +348,7 @@ static bool map_animation_invalidate_track_whirlpool(int x, int y, int baseZ)
 
 		if (mapElement->properties.track.type == TRACK_ELEM_WHIRLPOOL) {
 			int z = mapElement->base_height * 8;
-			map_invalidate_tile(x, y, z + 14, z + 18);
+			map_invalidate_tile_zoom1(x, y, z + 14, z + 18);
 			return false;
 		}
 	} while (!map_element_is_last_for_tile(mapElement++));
@@ -373,7 +373,7 @@ static bool map_animation_invalidate_track_spinningtunnel(int x, int y, int base
 
 		if (mapElement->properties.track.type == TRACK_ELEM_SPINNING_TUNNEL) {
 			int z = mapElement->base_height * 8;
-			map_invalidate_tile(x, y, z + 14, z + 32);
+			map_invalidate_tile_zoom1(x, y, z + 14, z + 32);
 			return false;
 		}
 	} while (!map_element_is_last_for_tile(mapElement++));
@@ -406,7 +406,7 @@ static bool map_animation_invalidate_banner(int x, int y, int baseZ)
 			continue;
 		
 		baseZ = mapElement->base_height * 8;
-		map_invalidate_tile(x, y, baseZ, baseZ + 16);
+		map_invalidate_tile_zoom1(x, y, baseZ, baseZ + 16);
 		return false;
 	} while (!map_element_is_last_for_tile(mapElement++));
 
@@ -433,7 +433,7 @@ static bool map_animation_invalidate_large_scenery(int x, int y, int baseZ)
 		sceneryEntry = g_largeSceneryEntries[mapElement->properties.scenery.type & 0x3FF];
 		if (sceneryEntry->large_scenery.flags & (1 << 3)) {
 			int z = mapElement->base_height * 8;
-			map_invalidate_tile(x, y, z, z + 16);
+			map_invalidate_tile_zoom1(x, y, z, z + 16);
 			wasInvalidated = true;
 		}
 	} while (!map_element_is_last_for_tile(mapElement++));
@@ -488,7 +488,7 @@ static bool map_animation_invalidate_wall_unknown(int x, int y, int baseZ)
 		mapElement->properties.fence.item[2] = bl;
 		if (di & 1) {
 			int z = mapElement->base_height * 8;
-			map_invalidate_tile(x, y, z, z + 32);
+			map_invalidate_tile_zoom1(x, y, z, z + 32);
 		}
 		if (di & 2)
 			wasInvalidated = true;
@@ -519,7 +519,7 @@ static bool map_animation_invalidate_wall(int x, int y, int baseZ)
 			continue;
 
 		int z = mapElement->base_height * 8;
-		map_invalidate_tile(x, y, z, z + 16);
+		map_invalidate_tile_zoom1(x, y, z, z + 16);
 		wasInvalidated = true;
 	} while (!map_element_is_last_for_tile(mapElement++));
 
diff --git a/src/world/park.c b/src/world/park.c
index 627c806e10..2cb4a1e96d 100644
--- a/src/world/park.c
+++ b/src/world/park.c
@@ -715,81 +715,6 @@ int park_get_entrance_index(int x, int y, int z)
 	return -1;
 }
 
-static void translate_3d_to_2d(int rotation, int *x, int *y)
-{
-	int rx, ry;
-
-	switch (rotation & 3) {
-	case 0:
-		rx = (*y) - (*x);
-		ry = (*x) + (*y);
-		break;
-	case 1:
-		rx = -(*x) - (*y);
-		ry = (*y) - (*x);
-		break;
-	case 2:
-		rx = (*x) - (*y);
-		ry = -(*x) - (*y);
-		break;
-	case 3:
-		rx = (*x) + (*y);
-		ry = (*x) - (*y);
-		break;
-	}
-	ry /= 2;
-
-	*x = rx;
-	*y = ry;
-}
-
-/**
- *
- *  rct2: 0x006EC847
- */
-void gfx_invalidate_viewport_tile(int x, int y, int z0, int z1)
-{
-	int x1, y1, x2, y2;
-	rct_viewport *viewport;
-
-	x += 16;
-	y += 16;
-	translate_3d_to_2d(RCT2_GLOBAL(RCT2_ADDRESS_CURRENT_ROTATION, uint32), &x, &y);
-
-	x1 = x - 32;
-	y1 = y - 32 - z1;
-	x2 = x + 32;
-	y2 = y + 32 - z0;
-
-	viewport = RCT2_GLOBAL(RCT2_ADDRESS_ACTIVE_VIEWPORT_PTR_ARRAY, rct_viewport*);
-	while (viewport->width != 0) {
-		int viewport_x2 = viewport->view_x + viewport->view_width;
-		int viewport_y2 = viewport->view_y + viewport->view_height;
-		if (x2 > viewport->view_x && y2 > viewport->view_y) {
-			x1 = max(x1, viewport->view_x);
-			y1 = max(y1, viewport->view_y);
-			x2 = min(x2, viewport_x2);
-			y2 = min(y2, viewport_y2);
-
-			uint8 zoom = 1 << viewport->zoom;
-			x1 -= viewport->view_x;
-			y1 -= viewport->view_y;
-			x2 -= viewport->view_x;
-			y2 -= viewport->view_y;
-			x1 /= zoom;
-			y1 /= zoom;
-			x2 /= zoom;
-			y2 /= zoom;
-			x1 += viewport->x;
-			y1 += viewport->y;
-			x2 += viewport->x;
-			y2 += viewport->y;
-			gfx_set_dirty_blocks(x1, y1, x2, y2);
-		}
-		viewport++;
-	}
-}
-
 /**
 *
 *  rct2: 0x00664D05
@@ -850,7 +775,7 @@ void update_park_fences(int x, int y)
 	if (sufaceElement->properties.surface.ownership != newOwnership) {
 		int z0 = sufaceElement->base_height * 8;
 		int z1 = z0 + 16;
-		gfx_invalidate_viewport_tile(x, y, z0, z1);	
+		map_invalidate_tile(x, y, z0, z1);	
 		sufaceElement->properties.surface.ownership = newOwnership;
 	}
 }
@@ -868,7 +793,7 @@ void park_remove_entrance_segment(int x, int y, int z)
 		if (mapElement->properties.entrance.type != ENTRANCE_TYPE_PARK_ENTRANCE)
 			continue;
 
-		gfx_invalidate_viewport_tile(x, y, mapElement->base_height * 8, mapElement->clearance_height * 8);
+		map_invalidate_tile(x, y, mapElement->base_height * 8, mapElement->clearance_height * 8);
 		map_element_remove(mapElement);
 		update_park_fences(x, y);
 	} while (!map_element_is_last_for_tile(mapElement++));
@@ -1057,7 +982,7 @@ int map_buy_land_rights_for_tile(int x, int y, int setting, int flags) {
 				TILE_MAP_ELEMENT_POINTER(tile_idx)->properties.surface.ownership |= OWNERSHIP_CONSTRUCTION_RIGHTS_OWNED;
 				uint16 baseHeight = TILE_MAP_ELEMENT_POINTER(tile_idx)->base_height;
 				baseHeight *= 8;
-				gfx_invalidate_viewport_tile(x, y, baseHeight, baseHeight + 16);
+				map_invalidate_tile(x, y, baseHeight, baseHeight + 16);
 			}
 			cost = RCT2_GLOBAL(RCT2_ADDRESS_CONSTRUCTION_RIGHTS_COST, uint16);
 			return cost;
@@ -1068,7 +993,7 @@ int map_buy_land_rights_for_tile(int x, int y, int setting, int flags) {
 			TILE_MAP_ELEMENT_POINTER(tile_idx)->properties.surface.ownership &= 0xEF;
 			uint16 baseHeight = TILE_MAP_ELEMENT_POINTER(tile_idx)->base_height;
 			baseHeight *= 8;
-			gfx_invalidate_viewport_tile(x, y, baseHeight, baseHeight + 16);
+			map_invalidate_tile(x, y, baseHeight, baseHeight + 16);
 		}
 		cost = 0;
 		break;
@@ -1078,7 +1003,7 @@ int map_buy_land_rights_for_tile(int x, int y, int setting, int flags) {
 			TILE_MAP_ELEMENT_POINTER(tile_idx)->properties.surface.ownership |= OWNERSHIP_AVAILABLE;
 			uint16 baseHeight = TILE_MAP_ELEMENT_POINTER(tile_idx)->base_height;
 			baseHeight *= 8;
-			gfx_invalidate_viewport_tile(x, y, baseHeight, baseHeight + 16);
+			map_invalidate_tile(x, y, baseHeight, baseHeight + 16);
 		}
 		cost = 0;
 		break;
@@ -1087,7 +1012,7 @@ int map_buy_land_rights_for_tile(int x, int y, int setting, int flags) {
 			TILE_MAP_ELEMENT_POINTER(tile_idx)->properties.surface.ownership |= OWNERSHIP_CONSTRUCTION_RIGHTS_AVAILABLE;
 			uint16 baseHeight = TILE_MAP_ELEMENT_POINTER(tile_idx)->base_height;
 			baseHeight *= 8;
-			gfx_invalidate_viewport_tile(x, y, baseHeight, baseHeight + 16);
+			map_invalidate_tile(x, y, baseHeight, baseHeight + 16);
 		}
 		cost = 0;
 		break;
diff --git a/src/world/park.h b/src/world/park.h
index 855454434c..f50cd9dd93 100644
--- a/src/world/park.h
+++ b/src/world/park.h
@@ -80,7 +80,7 @@ void game_command_remove_park_entrance(int *eax, int *ebx, int *ecx, int *edx, i
 void game_command_set_park_name(int *eax, int *ebx, int *ecx, int *edx, int *esi, int *edi, int *ebp);
 void game_command_buy_land_rights(int *eax, int *ebx, int *ecx, int *edx, int *esi, int *edi, int *ebp);
 
-void gfx_invalidate_viewport_tile(int x, int y, int z0, int z1);
+void map_invalidate_tile(int x, int y, int z0, int z1);
 
 void park_remove_ghost_entrance();
 money32 park_place_ghost_entrance(int x, int y, int z, int direction);
diff --git a/src/world/scenery.c b/src/world/scenery.c
index 3a05927927..cbf9bf3ca3 100644
--- a/src/world/scenery.c
+++ b/src/world/scenery.c
@@ -82,7 +82,7 @@ void scenery_update_age(int x, int y, rct_map_element *mapElement)
 		case MAP_ELEMENT_TYPE_SCENERY_MULTIPLE:
 		case MAP_ELEMENT_TYPE_ENTRANCE:
 		case MAP_ELEMENT_TYPE_PATH:
-			map_invalidate_tile(x, y, mapElementAbove->base_height * 8, mapElementAbove->clearance_height * 8);
+			map_invalidate_tile_zoom1(x, y, mapElementAbove->base_height * 8, mapElementAbove->clearance_height * 8);
 			scenery_increase_age(x, y, mapElement);
 			return;
 		case MAP_ELEMENT_TYPE_SCENERY:
@@ -97,7 +97,7 @@ void scenery_update_age(int x, int y, rct_map_element *mapElement)
 	
 	// Reset age / water plant
 	mapElement->properties.scenery.age = 0;
-	map_invalidate_tile(x, y, mapElement->base_height * 8, mapElement->clearance_height * 8);
+	map_invalidate_tile_zoom1(x, y, mapElement->base_height * 8, mapElement->clearance_height * 8);
 }
 
 void scenery_increase_age(int x, int y, rct_map_element *mapElement)
@@ -107,7 +107,7 @@ void scenery_increase_age(int x, int y, rct_map_element *mapElement)
 
 	if (mapElement->properties.scenery.age < 255) {
 		mapElement->properties.scenery.age++;
-		map_invalidate_tile(x, y, mapElement->base_height * 8, mapElement->clearance_height * 8);
+		map_invalidate_tile_zoom1(x, y, mapElement->base_height * 8, mapElement->clearance_height * 8);
 	}
 }