UnityCACAO-HDRP17/com.unity.visualeffectgraph/Documentation~/Operator-CustomHLSL.md

Custom HLSL Operator

Menu Path : Operator > HLSL > Custom HLSL

The Custom HLSL Operator allows you to write an HLSL function that takes inputs and produce outputs. See common documentation for Custom HLSL Operator and Custom HLSL Block here.

Function specific constraints

• Return type cannot be void
• Function parameters must not be of type VFXAttributes

To each function parameter will match an operator input, and the return value will match the operator output. If you use the access modifier out or inout for some input parameters, then they will also generate an output port.

Here is an example of a valid function declaration:

float Distance(in float3 a, in float3 b)
{
  return distance(a, b);
}

Another example with an out modifier:

bool IsClose(in float3 a, in float3 b, float threshold, out float d)
{
  d = distance(a, b);
  if (d >= threshold)
    return true;
  return false;
}

A sample with comments

/// a: the tooltip for parameter a
/// b: the tooltip for parameter b
float Distance(in float3 a, in float3 b)
{
  return distance(a, b);
}