(svn r3130) Calculate shorter wagon lengths more precisely in train depot window. This affects wagon position, the scroll bar, and the train length counter. No trial and error is required to get the correct length now.

1 files changed, 24 insertions, 24 deletions

diff --git a/train_gui.c b/train_gui.c
index fcc0cd98f..9af16a1ee 100644
--- a/train_gui.c
+++ b/train_gui.c
@@ -345,29 +345,38 @@ static void ShowBuildTrainWindow(TileIndex tile)
 	}
 }
 
+/**
+ * Get the number of pixels for the given wagon length.
+ * @param len Length measured in 1/8ths of a standard wagon.
+ * @return Number of pixels across.
+ */
+static int WagonLengthToPixels(int len) {
+	return (len * 29) / 8;
+}
+
 static void DrawTrainImage(const Vehicle *v, int x, int y, int count, int skip, VehicleID selection)
 {
-	int max_x = x + count * 29;
+	int dx = 0;
+	count *= 8;
 
 	do {
 		if (--skip < 0) {
 			int image = GetTrainImage(v, 6);
 			uint32 ormod = SPRITE_PALETTE(PLAYER_SPRITE_COLOR(v->owner));
-			int width = v->u.rail.cached_veh_length * 3;
+			int width = v->u.rail.cached_veh_length;
 
-			if (x + width + 4 <= max_x) {
+			if (dx + width <= count) {
 				if (v->vehstatus & VS_CRASHED)
 					ormod = PALETTE_CRASH;
-				DrawSprite(image | ormod, x + 14, y + 6 + (is_custom_sprite(RailVehInfo(v->engine_type)->image_index) ? _traininfo_vehicle_pitch : 0));
+				DrawSprite(image | ormod, x + 14 + WagonLengthToPixels(dx), y + 6 + (is_custom_sprite(RailVehInfo(v->engine_type)->image_index) ? _traininfo_vehicle_pitch : 0));
 				if (v->index == selection)
-					DrawFrameRect(x - 1, y - 1, x + width + 4, y + 12, 15, FR_BORDERONLY);
+					DrawFrameRect(x - 1 + WagonLengthToPixels(dx), y - 1, x + WagonLengthToPixels(dx + width) - 1, y + 12, 15, FR_BORDERONLY);
 			}
-			x += width + 5;
+			dx += width;
 		}
 
-		if (!(v = v->next))
-			break;
-	} while (x < max_x);
+		v = v->next;
+	} while (dx < count && v != NULL);
 }
 
 static void DrawTrainDepotWindow(Window *w)
@@ -385,7 +394,7 @@ static void DrawTrainDepotWindow(Window *w)
 
 	/* determine amount of items for scroller */
 	num = 0;
-	hnum = 1;
+	hnum = 8;
 	FOR_ALL_VEHICLES(v) {
 		if (v->type == VEH_Train &&
 			  (v->subtype == TS_Front_Engine || v->subtype == TS_Free_Car) &&
@@ -394,10 +403,7 @@ static void DrawTrainDepotWindow(Window *w)
 			num++;
 			// determine number of items in the X direction.
 			if (v->subtype == TS_Front_Engine) {
-				i = 0;
-				u = v;
-				do i++; while ((u = u->next) != NULL);
-				if (i > hnum) hnum = i;
+				hnum = max(hnum, v->u.rail.cached_total_length);
 			}
 		}
 	}
@@ -406,7 +412,7 @@ static void DrawTrainDepotWindow(Window *w)
 	num++;
 
 	SetVScrollCount(w, num);
-	SetHScrollCount(w, hnum);
+	SetHScrollCount(w, (hnum + 7) / 8);
 
 	/* locate the depot struct */
 	depot = GetDepotByTile(tile);
@@ -429,14 +435,8 @@ static void DrawTrainDepotWindow(Window *w)
 			SetDParam(0, v->unitnumber);
 			DrawString(x, y, (v->max_age - 366 < v->age) ? STR_00E3 : STR_00E2, 0);
 
-			/*Draw the train counter */
-			i = 0;
-			u = v;
-			do {
-				i += u->u.rail.cached_veh_length + 1;
-			} while ( (u=u->next) != NULL);			//Determine length of train
-
-			SetDParam(0, (i + 8) / 9);			//Set the counter
+			// Number of wagons relative to a standard length wagon (rounded up)
+			SetDParam(0, (v->u.rail.cached_total_length + 7) / 8);
 			DrawStringRightAligned(w->widget[6].right - 1, y + 4, STR_TINY_BLACK, 0);	//Draw the counter
 
 			/* Draw the pretty flag */
@@ -525,7 +525,7 @@ found_it:
 	while (skip--) v = v->next;
 
 	/* find the vehicle in this row that was clicked */
-	while ((x -= v->u.rail.cached_veh_length * 3 + 5) >= 0) {
+	while ((x -= WagonLengthToPixels(v->u.rail.cached_veh_length)) >= 0) {
 		v = v->next;
 		if (v == NULL) break;
 	}