Kaying node from tomato branch

Merge keying node from tomato branch into trunk.

It was considered stable and helpful by Mango team and it'll help
studio pipeline, because nodes would stop disappearing when opening
files in current trunk.

Full information about keying nodes could be found there:
http://wiki.blender.org/index.php/User:Nazg-gul/Keying

1 files changed, 115 insertions, 0 deletions

diff --git a/source/blender/compositor/operations/COM_KeyingOperation.cpp b/source/blender/compositor/operations/COM_KeyingOperation.cpp
new file mode 100644
index 00000000000..fba4dc65faf
--- /dev/null
+++ b/source/blender/compositor/operations/COM_KeyingOperation.cpp
@@ -0,0 +1,115 @@
+/*
+ * Copyright 2012, Blender Foundation.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Contributor:
+ *		Jeroen Bakker
+ *		Monique Dewanchand
+ *		Sergey Sharybin
+ */
+
+#include "COM_KeyingOperation.h"
+
+#include "MEM_guardedalloc.h"
+
+#include "BLI_listbase.h"
+#include "BLI_math.h"
+
+static int get_pixel_primary_channel(float pixelColor[4])
+{
+	float max_value = MAX3(pixelColor[0], pixelColor[1], pixelColor[2]);
+
+	if (max_value == pixelColor[0])
+		return 0;
+	else if (max_value == pixelColor[1])
+		return 1;
+
+	return 2;
+}
+
+static float get_pixel_saturation(float pixelColor[4], float screen_balance, int primary_channel)
+{
+	int other_1 = (primary_channel + 1) % 3;
+	int other_2 = (primary_channel + 2) % 3;
+
+	float min = MIN2(pixelColor[other_1], pixelColor[other_2]);
+	float max = MAX2(pixelColor[other_1], pixelColor[other_2]);
+	float val = screen_balance * min + (1.0f - screen_balance) * max;
+
+	return (pixelColor[primary_channel] - val) * fabsf(1.0f - val);
+}
+
+KeyingOperation::KeyingOperation(): NodeOperation()
+{
+	this->addInputSocket(COM_DT_COLOR);
+	this->addInputSocket(COM_DT_COLOR);
+	this->addOutputSocket(COM_DT_VALUE);
+
+	this->screenBalance = 0.5f;
+
+	this->pixelReader = NULL;
+	this->screenReader = NULL;
+}
+
+void KeyingOperation::initExecution()
+{
+	this->pixelReader = this->getInputSocketReader(0);
+	this->screenReader = this->getInputSocketReader(1);
+}
+
+void KeyingOperation::deinitExecution()
+{
+	this->pixelReader = NULL;
+	this->screenReader = NULL;
+}
+
+void KeyingOperation::executePixel(float *color, float x, float y, PixelSampler sampler, MemoryBuffer *inputBuffers[])
+{
+	float pixelColor[4];
+	float screenColor[4];
+
+	this->pixelReader->read(pixelColor, x, y, sampler, inputBuffers);
+	this->screenReader->read(screenColor, x, y, sampler, inputBuffers);
+
+	int primary_channel = get_pixel_primary_channel(screenColor);
+
+	float saturation = get_pixel_saturation(pixelColor, this->screenBalance, primary_channel);
+	float screen_saturation = get_pixel_saturation(screenColor, this->screenBalance, primary_channel);
+
+	if (saturation < 0) {
+		color[0] = 1.0f;
+	}
+	else if (saturation >= screen_saturation) {
+		color[0] = 0.0f;
+	}
+	else {
+		float distance = 1.0f - saturation / screen_saturation;
+
+		color[0] = distance;
+	}
+}
+
+bool KeyingOperation::determineDependingAreaOfInterest(rcti *input, ReadBufferOperation *readOperation, rcti *output)
+{
+	rcti newInput;
+
+	newInput.xmin = 0;
+	newInput.ymin = 0;
+	newInput.xmax = this->getWidth();
+	newInput.ymax = this->getHeight();
+
+	return NodeOperation::determineDependingAreaOfInterest(&newInput, readOperation, output);
+}