From f7c02af1849eb73b6abdebfd742b75a319f704f4 Mon Sep 17 00:00:00 2001
From: Lawrence Lee <billee@ucdavis.edu>
Date: Sun, 9 Aug 2020 17:22:23 -0700
Subject: [PATCH] Fix rendering of blank vectorscope

---
 rtgui/histogrampanel.cc | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/rtgui/histogrampanel.cc b/rtgui/histogrampanel.cc
index 65e2acfdf..ec8f9a326 100644
--- a/rtgui/histogrampanel.cc
+++ b/rtgui/histogrampanel.cc
@@ -1367,7 +1367,8 @@ void HistogramArea::drawVectorscope(Cairo::RefPtr<Cairo::Context> &cr, int w, in
         vect_width * (h - 2 * padding) > vect_height * (w - 2 * padding);
     const float scope_scale = fit_width ?
         (w - 2 * padding) / vect_width : (h - 2 * padding) / vect_height;
-    const float scope_size = scope_scale * max<float>(vect_width, vect_height);
+    const float scope_size = (vectorscope_scale > 0) ?
+        scope_scale * max<float>(vect_width, vect_height) : min<float>(w, h) - 2 * padding;
     const float o_x = (w - scope_scale * vect_width) / 2;
     const float o_y = (h - scope_scale * vect_height) / 2;
     const double s = RTScalable::getScale();