Motion vectors render pass in URP

Understand how the MotionVectors render pass renders the motion vector texture.

Location in the frame loop

URP renders motion vectors at the BeforeRenderingPostProcessing event. Before that event the motion vector texture might not be set or might contain previous frame’s motion vector data.

MotionVectors pass structure

URP renders the motion vector texture in 2 steps:

1. URP renders the cameraA component which creates an image of a particular viewpoint in your scene. The output is either drawn to the screen or captured as a texture. More info
   See in Glossary motion vectors in the MotionVectors full-screen pass. This pass uses the depth texture and the camera matrices for the current and the previous frames to calculate the camera motion vectors. This pass has a fixed per-camera computation load and does not require special motion vector support from renderers or materials.

2. URP draws a per-object motion vector shaderA program that runs on the GPU. More info
   See in Glossary pass for each renderer and material combination that supports motion vectors.