SplitViewer node:

- fix thumbnail preview (previously it showed only one input)
- make SplitViewer node update even if the second input is not connected
- now it works when the first socket is connected to a zero-sized node tree (e. g. Color Input node)
- SplitViewer node is now based on 2 operations: SplitOperation and ViewerOperation.
- ViewerBaseOperation was removed as a redundant one. Any future viewer style node can use the same principle and prepare the output before passing to an actual ViewerOperation.

Thanks Lukas Toenne for reviewing this patch and giving me get few pieces of advice.

1 files changed, 81 insertions, 0 deletions

diff --git a/source/blender/compositor/operations/COM_SplitOperation.cpp b/source/blender/compositor/operations/COM_SplitOperation.cpp
new file mode 100644
index 00000000000..a7dbccfc2f7
--- /dev/null
+++ b/source/blender/compositor/operations/COM_SplitOperation.cpp
@@ -0,0 +1,81 @@
+/*
+ * Copyright 2011, 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
+ */
+
+#include "COM_SplitOperation.h"
+#include "COM_SocketConnection.h"
+#include "BLI_listbase.h"
+#include "BKE_image.h"
+#include "BLI_utildefines.h"
+#include "BLI_math_color.h"
+#include "BLI_math_vector.h"
+
+extern "C" {
+	#include "MEM_guardedalloc.h"
+	#include "IMB_imbuf.h"
+	#include "IMB_imbuf_types.h"
+}
+
+
+SplitOperation::SplitOperation() : NodeOperation()
+{
+	this->addInputSocket(COM_DT_COLOR);
+	this->addInputSocket(COM_DT_COLOR);
+	this->addOutputSocket(COM_DT_COLOR);
+	this->m_image1Input = NULL;
+	this->m_image2Input = NULL;
+}
+
+void SplitOperation::initExecution()
+{
+	// When initializing the tree during initial load the width and height can be zero.
+	this->m_image1Input = getInputSocketReader(0);
+	this->m_image2Input = getInputSocketReader(1);
+}
+
+void SplitOperation::deinitExecution()
+{
+	this->m_image1Input = NULL;
+	this->m_image2Input = NULL;
+}
+
+void SplitOperation::executePixel(float output[4], float x, float y, PixelSampler sampler)
+{
+	int perc = this->m_xSplit ? this->m_splitPercentage * this->getWidth() / 100.0f : this->m_splitPercentage * this->getHeight() / 100.0f;
+	bool image1 = this->m_xSplit ? x > perc : y > perc;
+	if (image1) {
+		this->m_image1Input->read(output, x, y, COM_PS_NEAREST);
+	}
+	else {
+		this->m_image2Input->read(output, x, y, COM_PS_NEAREST);
+	}
+}
+
+void SplitOperation::determineResolution(unsigned int resolution[2], unsigned int preferredResolution[2])
+{
+	unsigned int tempPreferredResolution[2] = {0, 0};
+	unsigned int tempResolution[2];
+
+	this->getInputSocket(0)->determineResolution(tempResolution, tempPreferredResolution);
+	this->setResolutionInputSocketIndex((tempResolution[0] && tempResolution[1]) ? 0 : 1);
+
+	NodeOperation::determineResolution(resolution, preferredResolution);
+}