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BlinkScript

The BlinkScript node runs the The Foundry's Blink framework enabling us to write our code once and run it on any supported device. This is achieved through code translation, in which the Blink code is turned into specific code for each target device. Code is generated and compiled on-the-fly, allowing you to switch between devices at will.

BlinkScript runs a Blink "kernel" over every pixel in the output, where a Blink kernel is similar to a C++ class, but with some special parameter types and functions. Through translation, the code in the BlinkScript node can be turned into normal C++ or SIMD code for the CPU, or OpenCL for the GPU.

The Blink framework streamlines plug-in development workflow significantly, as you no longer have to exit Nuke to compile your code.

NOTE: GPU acceleration requires an NVIDIA GPU and drivers for CUDA 4.2 or above. To use the GPU when rendering from the command line, add --gpu to your command.

You can publish kernels in Group nodes which can then be saved as gizmos, if required. Published kernels can be encoded to protect your IP using BlinkScript's built-in kernel protection. Protected kernels are not readable when the published node is saved to a script.

WARNING: BlinkScript is very flexible, as there are no restrictions on the code you can write within a kernel. As a result, code complied from the Kernel Source can cause Nuke to crash, so please use caution!

Inputs and Controls

Connection Type	Connection Name	Function
input	src	The image to which the BlinkScript kernel is applied.

Control (UI)	Knob (Scripting)	Default Value	Function
BlinkScript Tab
Kernel File	kernelSourceFile	none	Sets the file path of the kernel used for Load and Save operations. BlinkScript kernels use the .rpp file extension.
Load	reloadKernelSourceFile	N/A	Click to load and compile the kernel specified in the Kernel File field.
Save	saveKernelFile	N/A	Click to save the current kernel to the location and file name specified in the Kernel File field.
Clear	clearKernelSource	N/A	Click to clear the Kernel Editor.
Recompile	recompile	N/A	Click to recompile the kernel currently in the Kernel Editor. Any compile errors present are displayed on screen.
Kernel Source
Kernel Editor	kernelSource	InvertKernel	Enter the kernel you intend to compile or edit the default InvertKernel to suit your purposes. Click the Recompile button to see the result of any changes.
Kernel Parameters Tab
Local GPU	gpuName	N/A	Displays the GPU used for rendering when Use GPU if available is enabled. Local GPU displays Not available when: • Use CPU is selected as the GPU Device in the Preferences. • no suitable GPU was found on your system. • it was not possible to create a context for processing on the selected GPU, such as when there is not enough free memory available on the GPU. You can select a different GPU Device, if available, by navigating to the Preferences and selecting an alternative from the GPU Device dropdown. NOTE: Selecting a different GPU requires you to restart Nuke before the change takes effect.
Use GPU if available	useGPUIfAvailable	enabled	When enabled, rendering occurs on the Local GPU specified, if available. NOTE: Enabling this option with no local GPU allows the script to run on the GPU whenever the script is opened on a machine which does have a GPU available. You should also select this if you wish to render from the command line with the --gpu option. The GPU processing also requires certain NVIDIA GPUs and CUDA drivers. For more information on the minimum requirements, please refer to the Nuke Release Notes available in Help > Release Notes.
Vectorize on CPU	vectorize	enabled	When enabled, use SIMD instructions on the CPU where possible. NOTE: This is currently an experimental feature and vectorization might fail for some valid Blink kernels.
Multiply	InvertKernel_Multiply	1	Multiplies the result of the InverKernel by this factor. NOTE: Multiply is the only control exposed by the default InvertKernel. For more information on writing kernels and some examples, see Help > Documentation.
Publish	publishButton	N/A	Click to create a Group node containing a copy of the current node. The Group can then be saved as a gizmo. The kernel parameters and GPU controls are exposed as user controls in the published version of the node.
Protect kernel	protectKernel WhenPublishing	disabled	When enabled, the kernel in the published group is encoded and is not readable when the published node is written to a script.
format	format	Dependent on Project Settings	Sets the output format when Specify output format is enabled, but otherwise defaults to the input format size.
Specify output format	specifiedFormat	disabled	When enabled, allows you to set the output format using the format control. Enabling this control also exposes the format dropdown in the published Group node.
Settings Tab
Percentage of GPU memory to use	maxGPUMemory	50	Sets the maximum percentage of GPU memory that is available for the BlinkScript node to allocate.
Percentage of image height per tile	maxTileLines	10	Sets the maximum percentage of the image height that the BlinkScript attempts to render in a single tile, that is, before updating the output. Processing is always done in tiles. On the CPU, the processing is sometimes done in scanlines rather than tiles, so this parameter does not always have an effect. See Help > Documentation for more information on when scanline processing is used on the CPU.