Blend POP

Summary

The Blend POP lets you blend together an attribute that occurs in all of it input POPs, such as the P attribute of all the inputs.

There are at least 8 blend types. The simplest blend types will do operations like average an attribute of all the inputs, or take the maximum, minimum, sum or product of all the inputs for one attribute.

The more complex blend types will mix based on a Blend Input factor (often a number between 0 and 1) for each input.

You can specify more than one point attribute, more than one vertex and more than one primitive attribute to blend at the same time.

You can get blend weights from attributes of the input POPs.

The Blend POP's architecture for handling multiple inputs is similar to the Attribute Combine POP.

Per-point mapping of parameters - The Random POP has a Map page, which allows every point to get a different value for the Blend Input weight parameter. In this mechanism, a separate attribute in the input contains values that override (or add to / multiply by) the parameter value. See Mapping POP Attributes to Parameters.

blendPOP_Class

Parameters - Blend Page

Blend Type blendtype - ⊞ - The Nth point of each input is blended according to this menu. The first group are simple blends, the last group depends on the weight of each input.

• Off off -

• Average avg -

• Add add -

• Multiply mul -

• Minimum min -

• Maximum max -

• Differencing differencing -

• Proportional proportional -

• Proportional Smoothed proportionalsmoothed -

Length Mismatch lengthmismatchnotif - ⊞ - Length mis-match motification action.

• Ignore ignore -

• Warning warning -

• Error error -

• Length Mismatch lengthmismatchnotif -

• Length Mismatch Action lengthmismatchaction - Specify which attribute values to use when sampling outside of the input range.

Blend Weights CHOP weightchop - Instead of the blend weights coling from parameters, they can come from a CHOP, wither one weight per channel, or one weight per sample.

Point Attribute Scope pointattrscope - ⊞ - The Point attribute scope to blend.

• * * -

Primitive Attribute Scope primattrscope - ⊞ - The Primitive attribute scope to blend.

• * * -

Vertex Attribute Scope vertattrscope - ⊞ - The Vertex attribute scope to blend.

• * * -

Input input - Start of Sequential Parameter Blocks managing the inputs of the POP.

In POP(s) input0pop - Input POPs for the current sequence block.

Blend Input input0weight - The weight for the current input.

Parameters - Map Page

Mapping map - Start of Sequential Parameter Blocks for attribute-to-parameter mapping.

OP map0op - Source OP for parameter mapping. The default of _in0 means the input POP.

Element map0element - The attribute (or component of an attribute) that will be mapped to a parameter per-point.

Parameter map0parm - ⊞ - Parameter on the current POP that will be mapped from the Element (the attribute).

• input0weight (Blend Input) input0weight -

Combine Operation map0combineop - ⊞ - Combine operation for attribute value with parameter value.

• Set set -

• Multiply mult -

• Add add -

Parameters - Common Page

Bypass bypass - Pass through the first input to the output unchanged.

Free Extra GPU Memory freeextragpumem - Free memory that has accumulated when output memory has grown and shrunk.

Delete Input Attributes delinputattrs - Only output which attributes you specify in this POP - helps isolate attributes into a separate branch.

Operator Inputs

• Input 0: -

Info CHOP Channels

Extra Information for the Blend POP can be accessed via an Info CHOP.

Common Operator Info Channels

• total_cooks - Number of times the operator has cooked since the process started.

• cook_time - Duration of the last cook in milliseconds.

• cook_frame - Frame number when this operator was last cooked relative to the component timeline.

• cook_abs_frame - Frame number when this operator was last cooked relative to the absolute time.

• cook_start_time - Time in milliseconds at which the operator started cooking in the frame it was cooked.

• cook_end_time - Time in milliseconds at which the operator finished cooking in the frame it was cooked.

• cooked_this_frame - 1 if operator was cooked this frame.

• warnings - Number of warnings in this operator if any.

• errors - Number of errors in this operator if any.

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POPs (Point Operators) is a new Operator Family of TouchDesigner that runs on the GPU accelerated graphics card or chips, and creates/modifies 3D data which is rendered by the Render TOP or passed to devices like DMX lighting, LED arrays, lasers or other external systems.

An Operator Family which operate on Channels (a sequence of numbers (Samples)) which are used for animation, audio, mathematics, simulation, logic, UI construction, and data streamed from/to devices and protocols.

A parameter in most CHOPs that restricts which channels of that CHOP will be affected. Normally all channels of a CHOP are affected by the operator. TOPs have Channel Mask, a similar feature.

A surface type in SOPs that includes polygon, curve (NURBS and Bezier), patch (NURBS and Bezier) and other basic shapes like sphere, tube and metaball. Points and Primitives are part of the Geometry Detail, which is a part of a SOP.

A sequence of vertices form a Polygon in a SOP. Each vertex is an integer index into the Point List, and each Point holds an XYZ position and attributes like Normals and Texture Coordinates.

Any of the procedural data operators. OPs do all the work in TouchDesigner. They "cook" and output data to other OPs, which ultimately result in new images, data and audio being generated. See Node.

Every operator in TouchDesigner has a set of control Parameters that can be integer or floating point numbers, menus, binary toggles, text strings or operator paths, which determine the output of the operator.

An operator whose Bypass flag is set does nothing: All data going into its first input appears at its output unaffected.

The Graphics Processing Unit. This is the high-speed, many-core processor of the graphics card/chip that takes geometry, images and data from the CPU and creates images and processed data.

Attributes are data associated with POP geometry. Points, Vertex (Vertices) and Primitives (polygons, lines, etc) can have any number of attributes.