From 598e0bc06143bceac8dd705f8e855c68df3808ce Mon Sep 17 00:00:00 2001
From: Frank <91616163+softhack007@users.noreply.github.com>
Date: Mon, 18 Sep 2023 15:34:53 +0200
Subject: [PATCH] matrix: fix for a corner case (e.g. gapmaps)

workaround for a corner case; if the reference pixels falls into a "gap" then gPC returns BLACK. Solutions is to reject BLACK.
---
 wled00/FX.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/wled00/FX.cpp b/wled00/FX.cpp
index 31ff74aa..7cea200e 100644
--- a/wled00/FX.cpp
+++ b/wled00/FX.cpp
@@ -5303,6 +5303,7 @@ uint16_t mode_2Dmatrix(void) {                  // Matrix2D. By Jeremy Williams.
         oldSpawnColor = SEGMENT.getPixelColorXY(SEGENV.aux0, SEGENV.aux1);  // find color of previous spawns
         SEGENV.aux1 ++;                                                     // our sample pixel will be one row down the next time
     }
+    if ((oldSpawnColor == CRGB::Black) || (oldSpawnColor == trailColor)) oldSpawnColor = spawnColor; // reject "black", as it would mean that ALL pixels create trails
 
     // move pixels one row down. Falling codes keep color and add trail pixels; all others pixels are faded
     for (int row=rows-1; row>=0; row--) {