fix crash when building object has invalid heights/variations

LeftofZen · LeftofZen · commit 75a182d2c359 · 2026-01-29T23:48:23.000+11:00
diff --git a/Gui/ViewModels/LocoTypes/Objects/Building/BuildingComponentsViewModel.cs b/Gui/ViewModels/LocoTypes/Objects/Building/BuildingComponentsViewModel.cs
@@ -123,7 +123,12 @@ protected void RecomputeBuildingVariationViewModels(List<List<uint8_t>> building
 							YOffset = 0,
 						};
 
-						cumulativeOffset += buildingHeights[variationItem];
+						// this shouldn't be necessary to check, but some objects are fully invalid, eg USFIFACT, so without this
+						// check the editor will crash but we'd instead prefer to show the invalid object to allow fixing it
+						if (variationItem < buildingHeights.Count)
+						{
+							cumulativeOffset += buildingHeights[variationItem];
+						}
 						bs.Layers.Add(bl);
 					}
 				}

Original file line number	Diff line number	Diff line change
`@@ -123,7 +123,12 @@ protected void RecomputeBuildingVariationViewModels(List<List<uint8_t>> building`
`123`	`123`	`YOffset = 0,`
`124`	`124`	`};`
`125`	`125`
`126`		`- cumulativeOffset += buildingHeights[variationItem];`
	`126`	`+ // this shouldn't be necessary to check, but some objects are fully invalid, eg USFIFACT, so without this`
	`127`	`+ // check the editor will crash but we'd instead prefer to show the invalid object to allow fixing it`
	`128`	`+ if (variationItem < buildingHeights.Count)`
	`129`	`+ {`
	`130`	`+ cumulativeOffset += buildingHeights[variationItem];`
	`131`	`+ }`
`127`	`132`	`bs.Layers.Add(bl);`
`128`	`133`	`}`
`129`	`134`	`}`