From 515a657b91794274f11c0f0f30eb60d64269554f Mon Sep 17 00:00:00 2001
From: tildearrow <me@tildearrow.org>
Date: Sun, 6 Aug 2023 04:15:02 -0500
Subject: [PATCH] GUI: don't show pan effects if can't pan

issue #1331
---
 src/gui/effectList.cpp | 56 +++++++++++++++++++++++++++++++++---------
 1 file changed, 45 insertions(+), 11 deletions(-)

diff --git a/src/gui/effectList.cpp b/src/gui/effectList.cpp
index 2d1bd1f1..0be9b159 100644
--- a/src/gui/effectList.cpp
+++ b/src/gui/effectList.cpp
@@ -47,22 +47,56 @@ void FurnaceGUI::drawEffectList() {
       const char* prevName=NULL;
       for (int i=0; i<256; i++) {
         const char* name=e->getEffectDesc(i,cursor.xCoarse);
-        bool effectShow = true;
+        bool effectShow=true;
         if (name==prevName) {
           continue;
         }
         prevName=name;
         switch (fxColors[i]) {
-          case GUI_COLOR_PATTERN_EFFECT_MISC: effectShow = effectsShow[8]; break;
-          case GUI_COLOR_PATTERN_EFFECT_SONG: effectShow = effectsShow[1]; break;
-          case GUI_COLOR_PATTERN_EFFECT_SPEED: effectShow = effectsShow[3]; break;
-          case GUI_COLOR_PATTERN_EFFECT_TIME: effectShow = effectsShow[2]; break;
-          case GUI_COLOR_PATTERN_EFFECT_PITCH: effectShow = effectsShow[0]; break;
-          case GUI_COLOR_PATTERN_EFFECT_PANNING: effectShow = effectsShow[4]; break;
-          case GUI_COLOR_PATTERN_EFFECT_VOLUME: effectShow = effectsShow[5]; break;
-          case GUI_COLOR_PATTERN_EFFECT_SYS_PRIMARY: effectShow = effectsShow[6]; break;
-          case GUI_COLOR_PATTERN_EFFECT_SYS_SECONDARY: effectShow = effectsShow[7]; break;
-          default: effectShow = true; break;
+          case GUI_COLOR_PATTERN_EFFECT_MISC:
+            effectShow=effectsShow[8];
+            break;
+          case GUI_COLOR_PATTERN_EFFECT_SONG:
+            effectShow=effectsShow[1];
+            break;
+          case GUI_COLOR_PATTERN_EFFECT_SPEED:
+            effectShow=effectsShow[3];
+            break;
+          case GUI_COLOR_PATTERN_EFFECT_TIME:
+            effectShow=effectsShow[2];
+            break;
+          case GUI_COLOR_PATTERN_EFFECT_PITCH:
+            effectShow=effectsShow[0];
+            break;
+          case GUI_COLOR_PATTERN_EFFECT_PANNING:
+            effectShow=effectsShow[4];
+            break;
+          case GUI_COLOR_PATTERN_EFFECT_VOLUME:
+            effectShow=effectsShow[5];
+            break;
+          case GUI_COLOR_PATTERN_EFFECT_SYS_PRIMARY:
+            effectShow=effectsShow[6];
+            break;
+          case GUI_COLOR_PATTERN_EFFECT_SYS_SECONDARY:
+            effectShow=effectsShow[7];
+            break;
+          default:
+            effectShow=true;
+            break;
+        }
+        if (fxColors[i]==GUI_COLOR_PATTERN_EFFECT_PANNING) {
+          DivDispatch* dispatch=e->getDispatch(e->dispatchOfChan[cursor.xCoarse]);
+          if (dispatch!=NULL) {
+            int outputs=dispatch->getOutputCount();
+            if (outputs<2) {
+              effectShow=false;
+            }
+            if (outputs<3) {
+              if (i>=0x88 && i<=0x8f) {
+                effectShow=false;
+              }
+            }
+          }
         }
         if (name!=NULL && effectShow) {
           ImGui::TableNextRow();