Reflection (computer graphics)

Reflections on shiny surfaces like wood or tile can add to the photorealistic effects of a 3D rendering.

For rendering environment reflections there exist many techniques that differ in precision, computational and implementation complexity.

Reflections on planar surfaces, such as planar mirrors or water surfaces, can be computed simply and accurately in real time with two pass rendering — one for the viewer, one for the view in the mirror, usually with the help of stencil buffer.

[2] Reflections on non-planar (curved) surfaces are more challenging for real time rendering.

Unlike a standard computer reflection (and the Java water effect popular in first-generation web graphics), the wet floor effect involves a gradient and often a slant in the reflection, so that the mirrored image appears to be hovering over or resting on a wet floor.

Ray-traced model demonstrating specular reflection
Comparison of accurate reflections computed with path tracing (left), approximate reflections with environment mapping (middle), and screen space reflections (right)
Mirror on wall rendered with 100% reflection
The large sphere on the left is blue with its reflection marked as metallic. The large sphere on the right is the same color but does not have the metallic property selected.
The large sphere on the left has sharpness set to 100%. The sphere on the right has sharpness set to 50% which creates a blurry reflection.
The sphere on the left has normal, metallic reflection. The sphere on the right has the same parameters, except that the reflection is marked as "glossy".