From 398c7e5f9d9ff8c786cac8fe0134ae2e4596dbab Mon Sep 17 00:00:00 2001
From: Peter Nelson <peter1138@openttd.org>
Date: Thu, 21 Sep 2023 08:38:46 +0100
Subject: [PATCH] Codechange: Use new function to get a bitmask of empty cargo
 types.

---
 src/newgrf_roadstop.cpp | 11 ++---------
 src/newgrf_station.cpp  | 11 ++---------
 src/station_cmd.cpp     | 15 +++++++++++++++
 src/station_func.h      |  1 +
 4 files changed, 20 insertions(+), 18 deletions(-)

diff --git a/src/newgrf_roadstop.cpp b/src/newgrf_roadstop.cpp
index 983bc0d06e..1055ea84bb 100644
--- a/src/newgrf_roadstop.cpp
+++ b/src/newgrf_roadstop.cpp
@@ -385,15 +385,8 @@ void TriggerRoadStopRandomisation(Station *st, TileIndex tile, RoadStopRandomTri
 
 	uint32_t whole_reseed = 0;
 
-	CargoTypes empty_mask = 0;
-	if (trigger == RSRT_CARGO_TAKEN) {
-		/* Create a bitmask of completely empty cargo types to be matched */
-		for (CargoID i = 0; i < NUM_CARGO; i++) {
-			if (st->goods[i].cargo.TotalCount() == 0) {
-				SetBit(empty_mask, i);
-			}
-		}
-	}
+	/* Bitmask of completely empty cargo types to be matched. */
+	CargoTypes empty_mask = (trigger == RSRT_CARGO_TAKEN) ? GetEmptyMask(st) : 0;
 
 	uint32_t used_triggers = 0;
 	auto process_tile = [&](TileIndex cur_tile) {
diff --git a/src/newgrf_station.cpp b/src/newgrf_station.cpp
index 16106dc1c3..5fb5ceb752 100644
--- a/src/newgrf_station.cpp
+++ b/src/newgrf_station.cpp
@@ -962,15 +962,8 @@ void TriggerStationRandomisation(Station *st, TileIndex trigger_tile, StationRan
 	uint32_t whole_reseed = 0;
 	ETileArea area = ETileArea(st, trigger_tile, tas[trigger]);
 
-	CargoTypes empty_mask = 0;
-	if (trigger == SRT_CARGO_TAKEN) {
-		/* Create a bitmask of completely empty cargo types to be matched */
-		for (CargoID i = 0; i < NUM_CARGO; i++) {
-			if (st->goods[i].cargo.TotalCount() == 0) {
-				SetBit(empty_mask, i);
-			}
-		}
-	}
+	/* Bitmask of completely empty cargo types to be matched. */
+	CargoTypes empty_mask = (trigger == SRT_CARGO_TAKEN) ? GetEmptyMask(st) : 0;
 
 	/* Store triggers now for var 5F */
 	SetBit(st->waiting_triggers, trigger);
diff --git a/src/station_cmd.cpp b/src/station_cmd.cpp
index feb783bd74..12c30a33b8 100644
--- a/src/station_cmd.cpp
+++ b/src/station_cmd.cpp
@@ -502,6 +502,21 @@ CargoTypes GetAcceptanceMask(const Station *st)
 	return mask;
 }
 
+/**
+ * Get a mask of the cargo types that are empty at the station.
+ * @param st Station to query
+ * @return the empty mask
+ */
+CargoTypes GetEmptyMask(const Station *st)
+{
+	CargoTypes mask = 0;
+
+	for (CargoID i = 0; i < NUM_CARGO; i++) {
+		if (st->goods[i].cargo.TotalCount() == 0) SetBit(mask, i);
+	}
+	return mask;
+}
+
 /**
  * Items contains the two cargo names that are to be accepted or rejected.
  * msg is the string id of the message to display.
diff --git a/src/station_func.h b/src/station_func.h
index ad3b60b7ae..8e72a945f7 100644
--- a/src/station_func.h
+++ b/src/station_func.h
@@ -31,6 +31,7 @@ CargoArray GetAcceptanceAroundTiles(TileIndex tile, int w, int h, int rad, Cargo
 
 void UpdateStationAcceptance(Station *st, bool show_msg);
 CargoTypes GetAcceptanceMask(const Station *st);
+CargoTypes GetEmptyMask(const Station *st);
 
 const DrawTileSprites *GetStationTileLayout(StationType st, byte gfx);
 void StationPickerDrawSprite(int x, int y, StationType st, RailType railtype, RoadType roadtype, int image);