prevent z-level from changing after box select

if the player clicks the mouse too fast after finishing a selection

docs/changelog.txt

@@ -36,6 +36,7 @@ changelog.txt uses a syntax similar to RST, with a few special sequences:
 ## New Plugins
 
 ## Fixes
+- `automaterial`: fix the cursor jumping up a z level when clicking quickly after box select
 - `gui/create-item`: prevent materials list filter from intercepting sublist hotkeys
 - `tiletypes`: no longer resets dig priority to the default when updating other properties of a tile
 

plugins/automaterial.cpp

@@ -94,7 +94,7 @@ static bool show_box_selection = true;
 static bool hollow_selection = false;
 static deque<df::item*> box_select_materials;
 
-#define SELECTION_IGNORE_TICKS 10
+#define SELECTION_IGNORE_TICKS 1
 static int ignore_selection = SELECTION_IGNORE_TICKS;
 
 static map<int16_t, MaterialDescriptor> last_used_material;