Houdini 16.5 Nodes VOP nodes

Compute Tangents VOP node

Compute surface tangents in different ways.

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Parameters

Tangent Style

Controls how this node calculates the direction of anisotropic reflections/highlights.

Use Geometric Tangents

Use the geometric tangents (dPds, dPdt) automatically defined for the type of geometry being rendered. Since the geometry defines the tangents, the highlight is stable as the geometry moves and/or deforms. However, for polygonal geometry, this style of tangent calculation will have discontinuities / artifacts along edges.

Intrinsic World Space

Calculate tangents in world space. Tangents will be smooth across all types of geometry, but the highlights will change if the object moves through space.

Intrinsic Object Space

Calculate tangents in the shaded object’s local space. Tangents will be smooth across all geometry, but the highlights will change if the object deforms.

Compute From UV

Calculate tangents using UV attributes on the object. The U and V tangents will point in the directions of increasing U and V coordinates. As long as the UV coordinates are consistent and smooth, the highlight is stable as the geometry moves/transforms and smooth over polygonal surfaces.

Use Connected utan, vtan

Use the tangent values from the connected utan and vtan inputs. This option allows you to use VOPs connected to the inputs to compute the tangents yourself for maximum flexibility.

Inputs

uv

UV coordinates for use with "Compute From UV" tangent style.

N

Surface normal for use with Intrinsic World Space and Intrinsic Object Space tangent styles.

utan

Input tangent for use with "Use Connected" tangent style.

vtan

Input tangent for use with "Use Connected" tangent style.

Outputs

utan

The computed U tangent.

vtan

The computed V tangent.

Examples

The following examples include this node.

WornMetal Example for Curvature VOP node

This example shows how the curvature vop can be added to a shader network to add a worn or distressed look to your material.

VOP nodes