From 493da2a7bd9dffb62da6a33ade709ead1fc84676 Mon Sep 17 00:00:00 2001
From: casey langen <casey.langen@gmail.com>
Date: Wed, 8 Mar 2017 22:04:29 -0800
Subject: [PATCH] Improved DirectSound volume ramping algorithm.

---
 src/contrib/directsoundout/DirectSoundOut.cpp | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/src/contrib/directsoundout/DirectSoundOut.cpp b/src/contrib/directsoundout/DirectSoundOut.cpp
index ca1b48d07..e6f4a292c 100644
--- a/src/contrib/directsoundout/DirectSoundOut.cpp
+++ b/src/contrib/directsoundout/DirectSoundOut.cpp
@@ -158,14 +158,21 @@ void DirectSoundOut::SetVolume(double volume) {
 
     if (this->state != StateStopped) {
         if (this->secondaryBuffer) {
-            double db = (volume < 0.0001f)
-                ? DSBVOLUME_MIN
-                : log10(this->volume) * 6000.f;
+            /* normalize between 1 and 10000 (DSBVOLUME_MIN) */
+            double scaled = fabs(volume * 10000);
+            scaled = scaled < 0 ? 1 : scaled;
+
+            /* found on experts-exchange (20181717) */
+            double db = ((log10(scaled) / 4) * 10000) - 10000;
 
             if (db > DSBVOLUME_MAX) {
                 db = DSBVOLUME_MAX;
             }
 
+            if (db < DSBVOLUME_MIN) {
+                db = DSBVOLUME_MIN;
+            }
+
             this->secondaryBuffer->SetVolume((LONG) db);
         }
     }