From 97f8dfaca2a60e228b84aedbf71620f0c000412c Mon Sep 17 00:00:00 2001
From: "Jonathan \"Geenz\" Goodman" <geenz@geenzo.com>
Date: Thu, 14 May 2026 22:36:43 -0400
Subject: Add a background discard offset.

---
 indra/newview/app_settings/settings.xml | 12 ++++++++++++
 indra/newview/llviewertexture.cpp       | 11 ++++++++++-
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/indra/newview/app_settings/settings.xml b/indra/newview/app_settings/settings.xml
index 0f1b704dc9..e9d91b7add 100644
--- a/indra/newview/app_settings/settings.xml
+++ b/indra/newview/app_settings/settings.xml
@@ -11909,6 +11909,18 @@
       <key>Value</key>
       <real>0.011</real>
     </map>
+    <key>TextureBackgroundDiscardOffset</key>
+    <map>
+      <key>Comment</key>
+      <string>Backgrounded textures will only discard up to (dim_max - offset). e.g. a 2048 texture (dim_max 11) with offset 2 caps the background floor at discard 9. 0 disables the cap (background can drive to max discard).</string>
+      <key>Persist</key>
+      <integer>1</integer>
+      <key>Type</key>
+      <string>S32</string>
+      <key>Value</key>
+      <integer>2</integer>
+    </map>
+
     <key>TextureDistanceDiscardPower</key>
     <map>
       <key>Comment</key>
diff --git a/indra/newview/llviewertexture.cpp b/indra/newview/llviewertexture.cpp
index 79439b4d58..1e8951926e 100644
--- a/indra/newview/llviewertexture.cpp
+++ b/indra/newview/llviewertexture.cpp
@@ -3204,7 +3204,16 @@ void LLViewerLODTexture::processTextureStats()
             combined = llmax(combined, mStalenessFactor);
             if (!isAgentAvatarBoost(mBoostLevel))
             {
-                combined = llmax(combined, sBackgroundFactor);
+                // Background floor capped at (dim_max - offset) so we can
+                // keep some baseline quality while backgrounded.
+                static LLCachedControl<S32> bg_offset(gSavedSettings, "TextureBackgroundDiscardOffset", 2);
+                F32 bg = sBackgroundFactor;
+                if ((S32)bg_offset > 0 && dim_max_for_image > 0.f)
+                {
+                    F32 cap = llmax(dim_max_for_image - (F32)(S32)bg_offset, 0.f) / dim_max_for_image;
+                    bg = llmin(bg, cap);
+                }
+                combined = llmax(combined, bg);
             }
 
             // VRAM pressure: pow(combined, 1 - factor) bends the curve
-- 
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