From eb27d61197f80d735ee0f0f1508da94ed7d843a8 Mon Sep 17 00:00:00 2001
From: tildearrow <me@tildearrow.org>
Date: Tue, 21 May 2024 17:43:10 -0500
Subject: [PATCH] macroInt: fix rounding error when bottom>top

issue #1891
---
 src/engine/macroInt.cpp | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/engine/macroInt.cpp b/src/engine/macroInt.cpp
index 621eab424..97865cc93 100644
--- a/src/engine/macroInt.cpp
+++ b/src/engine/macroInt.cpp
@@ -143,7 +143,11 @@ void DivMacroStruct::doMacro(DivInstrumentMacro& source, bool released, bool tic
           if (!linger) has=false;
           break;
       }
-      val=ADSR_LOW+((pos+(ADSR_HIGH-ADSR_LOW)*pos)>>8);
+      if (ADSR_HIGH>ADSR_LOW) {
+        val=ADSR_LOW+((pos+(ADSR_HIGH-ADSR_LOW)*pos)>>8);
+      } else {
+        val=ADSR_LOW+(((ADSR_HIGH-ADSR_LOW)*pos-pos)>>8);
+      }
     }
     if (type==2) { // LFO
       lfoPos+=LFO_SPEED;
@@ -161,7 +165,11 @@ void DivMacroStruct::doMacro(DivInstrumentMacro& source, bool released, bool tic
           lfoOut=(lfoPos&512)?255:0;
           break;
       }
-      val=ADSR_LOW+((lfoOut+(ADSR_HIGH-ADSR_LOW)*lfoOut)>>8);
+      if (ADSR_HIGH>ADSR_LOW) {
+        val=ADSR_LOW+((lfoOut+(ADSR_HIGH-ADSR_LOW)*lfoOut)>>8);
+      } else {
+        val=ADSR_LOW+(((ADSR_HIGH-ADSR_LOW)*lfoOut-lfoOut)>>8);
+      }
     }
   }
 }