Compositor: Cryptomatte compositing node.

This patch adds a new matte node that implements the Cryptomatte specification.
It also incluces a custom eye dropper that works outside of a color picker.
Cryptomatte export for the Cycles render engine will be in a separate patch.

Reviewers: brecht

Reviewed By: brecht

Subscribers: brecht

Tags: #compositing

Differential Revision: https://developer.blender.org/D3531

2 files changed, 115 insertions, 0 deletions

diff --git a/source/blender/compositor/operations/COM_CryptomatteOperation.cpp b/source/blender/compositor/operations/COM_CryptomatteOperation.cpp
new file mode 100644
index 00000000000..9dd36863d37
--- /dev/null
+++ b/source/blender/compositor/operations/COM_CryptomatteOperation.cpp
@@ -0,0 +1,75 @@
+/*
+ * Copyright 2018, 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: Lukas Stockner, Stefan Werner
+ */
+
+#include "COM_CryptomatteOperation.h"
+
+CryptomatteOperation::CryptomatteOperation(size_t num_inputs) : NodeOperation()
+{
+	for(size_t i = 0; i < num_inputs; i++) {
+		this->addInputSocket(COM_DT_COLOR);
+	}
+	inputs.resize(num_inputs);
+	this->addOutputSocket(COM_DT_COLOR);
+	this->setComplex(true);
+}
+
+void CryptomatteOperation::initExecution()
+{
+	for (size_t i = 0; i < inputs.size(); i++) {
+		inputs[i] = this->getInputSocketReader(i);
+	}
+}
+
+void CryptomatteOperation::addObjectIndex(float objectIndex)
+{
+	if (objectIndex != 0.0f) {
+		m_objectIndex.push_back(objectIndex);
+	}
+}
+
+void CryptomatteOperation::executePixel(float output[4],
+                                   int x,
+                                   int y,
+                                   void *data)
+{
+	float input[4];
+	output[0] = output[1] = output[2] = output[3] = 0.0f;
+	for (size_t i = 0; i < inputs.size(); i++) {
+		inputs[i]->read(input, x, y, data);
+		if (i == 0) {
+			/* Write the frontmost object as false color for picking. */
+			output[0] = input[0];
+			uint32_t m3hash;
+			::memcpy(&m3hash, &input[0], sizeof(uint32_t));
+			/* Since the red channel is likely to be out of display range,
+			 * setting green and blue gives more meaningful images. */
+			output[1] = ((float) ((m3hash << 8)) / (float) UINT32_MAX);
+			output[2] = ((float) ((m3hash << 16)) / (float) UINT32_MAX);
+		}
+		for(size_t i = 0; i < m_objectIndex.size(); i++) {
+			if (m_objectIndex[i] == input[0]) {
+				output[3] += input[1];
+			}
+			if (m_objectIndex[i] == input[2]) {
+				output[3] += input[3];
+			}
+		}
+	}
+}
diff --git a/source/blender/compositor/operations/COM_CryptomatteOperation.h b/source/blender/compositor/operations/COM_CryptomatteOperation.h
new file mode 100644
index 00000000000..9ce02c048b3
--- /dev/null
+++ b/source/blender/compositor/operations/COM_CryptomatteOperation.h
@@ -0,0 +1,40 @@
+/*
+ * Copyright 2018, 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: Lukas Stockner, Stefan Werner
+ */
+
+#ifndef _COM_CryptomatteOperation_h
+#define _COM_CryptomatteOperation_h
+#include "COM_NodeOperation.h"
+
+
+class CryptomatteOperation : public NodeOperation {
+private:
+	std::vector<float> m_objectIndex;
+public:
+	std::vector<SocketReader *> inputs;
+
+	CryptomatteOperation(size_t num_inputs = 6);
+
+	void initExecution();
+	void executePixel(float output[4], int x, int y, void *data);
+
+	void addObjectIndex(float objectIndex);
+
+};
+#endif