Parallax Occlusion Mapping Node

Description

You can use the Parallax Occlusion Mapping (POM) Node to create a parallax effect that displaces a material's UVs and depth to create the illusion of depth inside that material.

If you experience texture sampling errors while using this node in a graph which includes Custom Function Nodes or Sub Graphs, it might be possible to resolve these errors by upgrading to version 10.3 or later.

When you assign the same Texture2D to a Parallax Occlusion Mapping Node and a Sample Texture 2D Node, you need to avoid transforming the UV coordinates twice. To prevent this, connect the Split Texture Transform Node’s Texture Only port to the Sample Texture 2D Node’s UV port.

Ports

Name	Direction	Type	Description
Heightmap	Input	Texture2D	The Texture that specifies the depth of the displacement.
Heightmap Sampler	Input	Sampler State	The Sampler to sample Heightmap with.
Amplitude	Input	Float	A multiplier to apply to the height of the Heightmap (in centimeters).
Steps	Input	Float	The number of steps that the linear search of the algorithm performs.
UVs	Input	Vector2	The UVs that the sampler uses to sample the Texture.
Lod	Input	Float	The level of detail to use to sample the Heightmap.
Lod Threshold	Input	Float	The Heightmap mip level where the Parallax Occlusion Mapping effect begins to fade out. This is equivalent to the Fading Mip Level Start property in the High Definition Render Pipeline's (HDRP) Lit Material.
Depth Offset	Output	Float	The offset to apply to the depth buffer to produce the illusion of depth. Connect this output to the Depth Offset on the Master Node to enable effects that rely on the depth buffer, such as shadows and screen space ambient occlusion.
Parallax UVs	Output	Vector2	UVs that you have added the parallax offset to.

Generated Code Example

The following example code represents one possible outcome of this node.

float3 ParallaxOcclusionMapping_ViewDir = IN.TangentSpaceViewDirection * GetDisplacementObjectScale().xzy;
float ParallaxOcclusionMapping_NdotV = ParallaxOcclusionMapping_ViewDir.z;
float ParallaxOcclusionMapping_MaxHeight = Amplitude * 0.01;

// Transform the view vector into the UV space.
float3 ParallaxOcclusionMapping_ViewDirUV    = normalize(float3(ParallaxOcclusionMapping_ViewDir.xy * ParallaxOcclusionMapping_MaxHeight, ParallaxOcclusionMapping_ViewDir.z)); // TODO: skip normalize

PerPixelHeightDisplacementParam ParallaxOcclusionMapping_POM;
ParallaxOcclusionMapping_POM.uv = UVs.xy;

float ParallaxOcclusionMapping_OutHeight;
float2 _ParallaxOcclusionMapping_ParallaxUVs = UVs.xy + ParallaxOcclusionMapping(Lod, Lod_Threshold, Steps, ParallaxOcclusionMapping_ViewDirUV, ParallaxOcclusionMapping_POM, ParallaxOcclusionMapping_OutHeight);

float _ParallaxOcclusionMapping_PixelDepthOffset = (ParallaxOcclusionMapping_MaxHeight - ParallaxOcclusionMapping_OutHeight * ParallaxOcclusionMapping_MaxHeight) / max(ParallaxOcclusionMapping_NdotV, 0.0001);