Points primitive is intended to be used for small particles such as sparks, snowflakes, or raindrops. They are optimized for the case where the intended particle is small, taking up at most a couple of pixels on the screen.

Types of Points

• Points with normals are rendered as disks.
• Points without normals: these are modeled as small spheres. These are real spheres that can be reflective and/or refractive. They can be used to model small water droplets though you should be aware that path tracing a large number of refractive droplets can be very costly.

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