Vector Field is a technical term that is extremely important in game graphics rendering and optimization (technical art). A technology that uses 3D texture assets that store 3D forces (wind direction and strength) at each coordinate in a 3D grid space to give particles complex, organic undulations.
An analogy in the real world: A synchronized fluid in which countless small fish (particles) swimming in a river swim undisturbed along the "violent eddies and currents (current velocity map)" of the water flow.
Vector Field is a ``3-dimensional transparent water flow design map (3D force field map) that clearly records the direction and strength of water flow'' at each point in the river. The particles are countless fallen leaves thrown into this river. The fallen leaves themselves try to move straight without thinking, but the moment they reach each coordinate, they read the water flow information (vector value) recorded at that location that says ``Water is flowing diagonally upward to the right with a force of 5'' and forcefully change their course smoothly along that flow. This creates an extremely high-quality fluid expression in which the particles move in sync, perfectly tracing the beautiful whirlpools and air currents.
Illustration: Vector Field Infographic that clearly illustrates the basic processing flow and mechanism of (vector field) in Japanese.
Detailed mechanism and operating principle
Attach the fluid data (.vf file or 3D texture) generated by an external tool (DCC tool) or DCC plug-in to the "Vector Field" node of VFX Graph, and sample and add the vector value of that force field to the particle.