SL-16418 optimize imageraw clear

1 files changed, 53 insertions, 35 deletions

diff --git a/indra/llimage/llimage.cpp b/indra/llimage/llimage.cpp
index 15b07e5318..2855612158 100644
--- a/indra/llimage/llimage.cpp
+++ b/indra/llimage/llimage.cpp
@@ -925,47 +925,65 @@ bool LLImageRaw::setSubImage(U32 x_pos, U32 y_pos, U32 width, U32 height,
 
 void LLImageRaw::clear(U8 r, U8 g, U8 b, U8 a)
 {
-	llassert( getComponents() <= 4 );
-	// This is fairly bogus, but it'll do for now.
-	if (isBufferInvalid())
-	{
-		LL_WARNS() << "Invalid image buffer" << LL_ENDL;
-		return;
-	}
+    LL_PROFILE_ZONE_NAMED("djh imageraw clear")
+    S8 components = getComponents();
+    llassert( components > 0 && components <= 4 );
 
-	U8 *pos = getData();
-	U32 x, y;
-	for (x = 0; x < getWidth(); x++)
-	{
-		for (y = 0; y < getHeight(); y++)
-		{
-			*pos = r;
-			pos++;
-			if (getComponents() == 1)
-			{
-				continue;
-			}
-			*pos = g;
-			pos++;
-			if (getComponents() == 2)
-			{
-				continue;
-			}
-			*pos = b;
-			pos++;
-			if (getComponents() == 3)
-			{
-				continue;
-			}
-			*pos = a;
-			pos++;
-		}
-	}
+    // This is fairly bogus, but it'll do for now.
+    if (isBufferInvalid())
+    {
+        LL_WARNS() << "Invalid image buffer" << LL_ENDL;
+        return;
+    }
+
+    switch (components)
+    {
+    case 1:
+        {
+            U8 *dst = getData();
+            S32 count = getWidth() * getHeight();
+            llassert(count == getDataSize());
+            std::fill_n(dst, count, r);
+            break;
+        }
+    case 2:
+        {
+            U16 *dst = (U16 *)getData();
+            S32 count = getWidth() * getHeight();
+            llassert(count == getDataSize() / 2);
+            U16 val = (U16)(r | g << 8);
+            std::fill_n(dst, count, val);
+            break;
+        }
+    case 3:
+        {
+            U8 *dst = getData();
+            S32 count = getWidth() * getHeight();
+            llassert(count == getDataSize() / 3);
+            for (S32 i = 0; i < count; i++)
+            {
+                *dst++ = r;
+                *dst++ = g;
+                *dst++ = b;
+            }
+            break;
+        }
+    case 4:
+        {
+            U32 *dst = (U32 *)getData();
+            S32 count = getWidth() * getHeight();
+            llassert(count == getDataSize() / 4);
+            U32 val = (U32)(r | g << 8 | b << 16 | a << 24);
+            std::fill_n(dst, count, val);
+            break;
+        }
+    }
 }
 
 // Reverses the order of the rows in the image
 void LLImageRaw::verticalFlip()
 {
+    LL_PROFILE_ZONE_SCOPED;
 	S32 row_bytes = getWidth() * getComponents();
 	llassert(row_bytes > 0);
 	std::vector<U8> line_buffer(row_bytes);