Fix usage of uninialized memory in some operations

- FastGaussianBlurValueOperation is a value operation, so use only first vector
  component in initializeTileData.

- Gamma correct/uncorrect operations didn't set alpha for output which lead to
  usage of uninitialzied memory further in nodes graph.

2 files changed, 4 insertions, 2 deletions

diff --git a/source/blender/compositor/operations/COM_FastGaussianBlurOperation.cpp b/source/blender/compositor/operations/COM_FastGaussianBlurOperation.cpp
index 4bdb2591cb7..2ae80b4f207 100644
--- a/source/blender/compositor/operations/COM_FastGaussianBlurOperation.cpp
+++ b/source/blender/compositor/operations/COM_FastGaussianBlurOperation.cpp
@@ -281,7 +281,7 @@ void *FastGaussianBlurValueOperation::initializeTileData(rcti *rect)
 		if (this->m_overlay == FAST_GAUSS_OVERLAY_MIN) {
 			float *src = newBuf->getBuffer();
 			float *dst = copy->getBuffer();
-			for (int i = copy->getWidth() * copy->getHeight() * COM_NUMBER_OF_CHANNELS; i != 0; i--, src++, dst++) {
+			for (int i = copy->getWidth() * copy->getHeight(); i != 0; i--, src += COM_NUMBER_OF_CHANNELS, dst += COM_NUMBER_OF_CHANNELS) {
 				if (*src < *dst) {
 					*dst = *src;
 				}
@@ -290,7 +290,7 @@ void *FastGaussianBlurValueOperation::initializeTileData(rcti *rect)
 		else if (this->m_overlay == FAST_GAUSS_OVERLAY_MAX) {
 			float *src = newBuf->getBuffer();
 			float *dst = copy->getBuffer();
-			for (int i = copy->getWidth() * copy->getHeight() * COM_NUMBER_OF_CHANNELS; i != 0; i--, src++, dst++) {
+			for (int i = copy->getWidth() * copy->getHeight(); i != 0; i--, src += COM_NUMBER_OF_CHANNELS, dst += COM_NUMBER_OF_CHANNELS) {
 				if (*src > *dst) {
 					*dst = *src;
 				}
diff --git a/source/blender/compositor/operations/COM_GammaCorrectOperation.cpp b/source/blender/compositor/operations/COM_GammaCorrectOperation.cpp
index c36a6f896c2..8f92dc02a57 100644
--- a/source/blender/compositor/operations/COM_GammaCorrectOperation.cpp
+++ b/source/blender/compositor/operations/COM_GammaCorrectOperation.cpp
@@ -48,6 +48,7 @@ void GammaCorrectOperation::executePixel(float output[4], float x, float y, Pixe
 	output[0] = inputColor[0] > 0.0f ? inputColor[0] * inputColor[0] : 0.0f;
 	output[1] = inputColor[1] > 0.0f ? inputColor[1] * inputColor[1] : 0.0f;
 	output[2] = inputColor[2] > 0.0f ? inputColor[2] * inputColor[2] : 0.0f;
+	output[3] = inputColor[3];
 
 	if (inputColor[3] > 0.0f) {
 		output[0] *= inputColor[3];
@@ -86,6 +87,7 @@ void GammaUncorrectOperation::executePixel(float output[4], float x, float y, Pi
 	output[0] = inputColor[0] > 0.0f ? sqrtf(inputColor[0]) : 0.0f;
 	output[1] = inputColor[1] > 0.0f ? sqrtf(inputColor[1]) : 0.0f;
 	output[2] = inputColor[2] > 0.0f ? sqrtf(inputColor[2]) : 0.0f;
+	output[3] = inputColor[3];
 
 	if (inputColor[3] > 0.0f) {
 		output[0] *= inputColor[3];