From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Mon, 19 Jul 2021 02:23:20 +0000 (+0100)
Subject: lowering: Only do clashing Z heavy when needed
X-Git-Tag: otter-0.7.2~24
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=commitdiff_plain;h=2052a9c8a139ff032ccda8579c3677d53480a346;p=otter.git

lowering: Only do clashing Z heavy when needed

If there are no pieces Q to insert, we con't need to worry about this,
because it'll just be an empty ignored plan entry.

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
---

diff --git a/templates/script.ts b/templates/script.ts
index 6f070409..1a069962 100644
--- a/templates/script.ts
+++ b/templates/script.ts
@@ -738,6 +738,7 @@ function lower_pieces(targets_todo: LowerTodoList):
   }
 
   while (nomove_heavy.length &&
+	 (tomove_light.length || tomove_misstacked.length) &&
 	 nomove_heavy[nomove_heavy.length-1].p.z == q_z_top) {
     // Yowzer.  We have to reset the Z coordinates on these heavy
     // pieces, whose Z coordinate is the same as the stuff we are not