From df8fe4d28bcf630bce36ac00dbbe848a8d30229c Mon Sep 17 00:00:00 2001
From: Daniel Schwabeneder <daschw@disroot.org>
Date: Wed, 10 Feb 2021 18:42:04 +0100
Subject: [PATCH] remove black lines from GR surface with equal-length x, y,
 and z input

---
 src/backends/gr.jl | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/src/backends/gr.jl b/src/backends/gr.jl
index bf6b439e6..83a5bcc39 100644
--- a/src/backends/gr.jl
+++ b/src/backends/gr.jl
@@ -1736,13 +1736,12 @@ end
 function gr_draw_surface(series, x, y, z, clims)
     if series[:seriestype] === :surface
         if length(x) == length(y) == length(z)
-            GR.trisurface(x, y, z)
-        else
-            try
-                GR.gr3.surface(x, y, z, GR.OPTION_COLORED_MESH)
-            catch
-                GR.surface(x, y, z, GR.OPTION_COLORED_MESH)
-            end
+            x, y, z = GR.gridit(x, y, z, 200, 200)
+        end
+        try
+            GR.gr3.surface(x, y, z, GR.OPTION_COLORED_MESH)
+        catch
+            GR.surface(x, y, z, GR.OPTION_COLORED_MESH)
         end
     else # wireframe
         GR.setfillcolorind(0)