1 files changed, 47 insertions, 5 deletions

diff --git a/indra/newview/llface.cpp b/indra/newview/llface.cpp
index ec7ea398f0..0a2e20fecd 100644
--- a/indra/newview/llface.cpp
+++ b/indra/newview/llface.cpp
@@ -1571,7 +1571,7 @@ bool LLFace::getGeometryVolume(const LLVolume& volume,
                 skin = mSkinInfo;
             }
 
-            //TODO -- cache this (check profile marker above)?
+            //TODO - cache this (check profile marker above)?
             glm::mat4 m = glm::make_mat4((F32*)skin->mBindShapeMatrix.getF32ptr());
             m = glm::transpose(glm::inverse(m));
             mat_normal.loadu(glm::value_ptr(m));
@@ -2259,7 +2259,18 @@ F32 LLFace::getTextureVirtualSize()
         face_area =  mPixelArea / llclamp(texel_area, 0.015625f, 128.f);
     }
 
-    face_area = LLFace::adjustPixelArea(mImportanceToCamera, face_area);
+    // Diffuse source area as the dim-aware hint for adjustPixelArea.
+    S32 source_area = 0;
+    if (mTexture[LLRender::DIFFUSE_MAP].notNull())
+    {
+        S32 sw = mTexture[LLRender::DIFFUSE_MAP]->getFullWidth();
+        S32 sh = mTexture[LLRender::DIFFUSE_MAP]->getFullHeight();
+        if (sw > 0 && sh > 0)
+        {
+            source_area = sw * sh;
+        }
+    }
+    face_area = LLFace::adjustPixelArea(mImportanceToCamera, face_area, source_area);
     if(face_area > LLViewerTexture::sMinLargeImageSize) //if is large image, shrink face_area by considering the partial overlapping.
     {
         if(mImportanceToCamera > LEAST_IMPORTANCE_FOR_LARGE_IMAGE && mTexture[LLRender::DIFFUSE_MAP].notNull() && mTexture[LLRender::DIFFUSE_MAP]->isLargeImage())
@@ -2280,6 +2291,8 @@ bool LLFace::calcPixelArea(F32& cos_angle_to_view_dir, F32& radius)
     // don't update every frame
     if (gFrameTimeSeconds - mLastPixelAreaUpdate < PIXEL_AREA_UPDATE_PERIOD)
     {
+        cos_angle_to_view_dir = mLastCosAngleToViewDir;
+        radius = mLastRadius;
         return true;
     }
 
@@ -2351,6 +2364,7 @@ bool LLFace::calcPixelArea(F32& cos_angle_to_view_dir, F32& radius)
             // no rigged extents, zero out bounding box and skip update
             mRiggedExtents[0] = mRiggedExtents[1] = LLVector4a(0.f, 0.f, 0.f);
 
+            mInFrustum = false;
             return false;
         }
 
@@ -2383,6 +2397,7 @@ bool LLFace::calcPixelArea(F32& cos_angle_to_view_dir, F32& radius)
 
     F32 dist = lookAt.getLength3().getF32();
     dist = llmax(dist-size.getLength3().getF32(), 0.001f);
+    mDistanceToCamera = dist;
 
     lookAt.normalize3fast() ;
 
@@ -2404,6 +2419,7 @@ bool LLFace::calcPixelArea(F32& cos_angle_to_view_dir, F32& radius)
         if(!camera->AABBInFrustum(center, size))
         {
             mImportanceToCamera = 0.f ;
+            mInFrustum = false;
             return false ;
         }
         if(cos_angle_to_view_dir > camera->getCosHalfFov()) //the center is within the view frustum
@@ -2432,6 +2448,24 @@ bool LLFace::calcPixelArea(F32& cos_angle_to_view_dir, F32& radius)
         mImportanceToCamera = LLFace::calcImportanceToCamera(cos_angle_to_view_dir, dist) ;
     }
 
+    // On-screen test: does the face's projected disc overlap the screen disc?
+    // (Same construction as adjustPartialOverlapPixelArea.) Behind-camera faces
+    // get acos(cos) near pi and fall out; the generous screen radius errs toward
+    // "on screen" so fetch admission never starves edge content. mFrustumOverflow
+    // is how far past the boundary the disc sits, as a fraction of screen size -
+    // 0 on screen, 0.1 = 10% of a screen out - and feeds the frustum allowance
+    // falloff in computeDesiredDiscard.
+    {
+        F32 center_px = acosf(llclamp(cos_angle_to_view_dir, -1.f, 1.f)) * LLDrawable::sCurPixelAngle;
+        F32 screen_radius = (F32)llmax(gViewerWindow->getWindowWidthRaw(), gViewerWindow->getWindowHeightRaw());
+        F32 past_edge = center_px - radius - screen_radius;
+        mInFrustum = past_edge <= 5.f;
+        mFrustumOverflow = llmax(past_edge - 5.f, 0.f) / screen_radius;
+    }
+
+    mLastCosAngleToViewDir = cos_angle_to_view_dir;
+    mLastRadius = radius;
+
     return true ;
 }
 
@@ -2507,8 +2541,16 @@ F32 LLFace::calcImportanceToCamera(F32 cos_angle_to_view_dir, F32 dist)
 }
 
 //static
-F32 LLFace::adjustPixelArea(F32 importance, F32 pixel_area)
+F32 LLFace::adjustPixelArea(F32 importance, F32 pixel_area, S32 source_area)
 {
+    // Dim-aware floor: source_area/256 lowers the "large but unimportant"
+    // clamp proportionally so smaller sources can be pushed past discard 4.
+    F32 large_floor = (F32)LLViewerTexture::sMinLargeImageSize;
+    if (source_area > 0)
+    {
+        large_floor = llmin(large_floor, (F32)source_area / 256.f);
+    }
+
     if(pixel_area > LLViewerTexture::sMaxSmallImageSize)
     {
         if(importance < LEAST_IMPORTANCE) //if the face is not important, do not load hi-res.
@@ -2516,11 +2558,11 @@ F32 LLFace::adjustPixelArea(F32 importance, F32 pixel_area)
             static const F32 MAX_LEAST_IMPORTANCE_IMAGE_SIZE = 128.0f * 128.0f ;
             pixel_area = llmin(pixel_area * 0.5f, MAX_LEAST_IMPORTANCE_IMAGE_SIZE) ;
         }
-        else if(pixel_area > LLViewerTexture::sMinLargeImageSize) //if is large image, shrink face_area by considering the partial overlapping.
+        else if(pixel_area > large_floor) //if is large image, shrink face_area by considering the partial overlapping.
         {
             if(importance < LEAST_IMPORTANCE_FOR_LARGE_IMAGE)//if the face is not important, do not load hi-res.
             {
-                pixel_area = (F32)LLViewerTexture::sMinLargeImageSize ;
+                pixel_area = large_floor ;
             }
         }
     }