From 52e31a4866ab8db0079c494348dfd642b6694935 Mon Sep 17 00:00:00 2001
From: Campbell Barton <ideasman42@gmail.com>
Date: Fri, 3 Aug 2012 09:51:10 +0000
Subject: fix for bokeh blur using uninitialized memory - it would cause some
 tiles not to be blurred.

was in fact a bug in MemoryBuffer::getMaximumValue
---
 .../blender/compositor/intern/COM_MemoryBuffer.cpp | 24 ++++++++++++++++------
 .../blender/compositor/intern/COM_MemoryBuffer.h   |  5 ++++-
 2 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/source/blender/compositor/intern/COM_MemoryBuffer.cpp b/source/blender/compositor/intern/COM_MemoryBuffer.cpp
index f8c842d8e67..eae98a1211f 100644
--- a/source/blender/compositor/intern/COM_MemoryBuffer.cpp
+++ b/source/blender/compositor/intern/COM_MemoryBuffer.cpp
@@ -105,13 +105,24 @@ float MemoryBuffer::getMaximumValue()
 	return result;
 }
 
-float MemoryBuffer::getMaximumValue(rcti* rect)
+float MemoryBuffer::getMaximumValue(rcti *rect)
 {
-	MemoryBuffer *temp = new MemoryBuffer(NULL, rect);
-	temp->copyContentFrom(this);
-	float result = temp->getMaximumValue();
-	delete temp;
-	return result;
+	rcti rect_clamp;
+
+	/* first clamp the rect by the bounds or we get un-initialized values */
+	BLI_rcti_isect(rect, &this->m_rect, &rect_clamp);
+
+	if (!BLI_rcti_is_empty(&rect_clamp)) {
+		MemoryBuffer *temp = new MemoryBuffer(NULL, &rect_clamp);
+		temp->copyContentFrom(this);
+		float result = temp->getMaximumValue();
+		delete temp;
+		return result;
+	}
+	else {
+		BLI_assert(0);
+		return 0.0f;
+	}
 }
 
 MemoryBuffer::~MemoryBuffer()
@@ -125,6 +136,7 @@ MemoryBuffer::~MemoryBuffer()
 void MemoryBuffer::copyContentFrom(MemoryBuffer *otherBuffer)
 {
 	if (!otherBuffer) {
+		BLI_assert(0);
 		return;
 	}
 	unsigned int otherY;
diff --git a/source/blender/compositor/intern/COM_MemoryBuffer.h b/source/blender/compositor/intern/COM_MemoryBuffer.h
index 411c5b9ad8a..f64603ed5d9 100644
--- a/source/blender/compositor/intern/COM_MemoryBuffer.h
+++ b/source/blender/compositor/intern/COM_MemoryBuffer.h
@@ -202,6 +202,9 @@ public:
 	/**
 	 * @brief add the content from otherBuffer to this MemoryBuffer
 	 * @param otherBuffer source buffer
+	 *
+	 * @note take care when running this on a new buffer since it wont fill in
+	 *       uninitialized values in areas where the buffers don't overlap.
 	 */
 	void copyContentFrom(MemoryBuffer *otherBuffer);
 	
@@ -229,7 +232,7 @@ public:
 	
 	float *convertToValueBuffer();
 	float getMaximumValue();
-	float getMaximumValue(rcti* rect);
+	float getMaximumValue(rcti *rect);
 private:
 	unsigned int determineBufferSize();
 
-- 
cgit v1.2.3