It is a gizmo that will allow you to create a refraction effect directly from nuke, using a geometry and a camera. It allows you to simulate different optical effects to achieve a result similar to glass. I hope you liked it.
Here you can see a video explaining how to use it, you may find a more updated version on nukepedia or github.
Refraction is a phenomenon that occurs when light passes through a transparent or translucent medium, such as air, water, or glass. When light passes through a refractive medium, it changes direction, and this change in direction is known as refraction.
In 3D rendering, refraction is simulated by calculating the path of light as it passes through a refractive medium and determining how the light’s direction is affected by the refraction. This is typically done using a technique called ray tracing, which involves tracing the path of individual rays of light as they pass through the 3D scene. When a ray of light encounters a refractive medium, the ray tracing algorithm calculates the refraction of the light based on the medium’s refractive index and the angle at which the light hits the medium. This calculation determines how the light’s direction is changed by the refraction, and this information is used to update the ray’s path and continue tracing its path through the 3D scene.
Overall, refraction is an important phenomenon in 3D rendering, as it allows for the realistic simulation of light passing through transparent or translucent objects, such as glass or water. By using ray tracing algorithms to calculate the refraction of light, 3D rendering software is able to accurately simulate the effects of refraction and create realistic-looking 3D scenes.
In Nuke, fake refractions are a technique for simulating the appearance of refraction without actually calculating the refraction of light in a 3D scene. This technique is used to create the illusion of refraction without the computational overhead and complexity of accurately simulating refraction in 3D.
To create fake refractions in Nuke, you can use the Transform node to apply a distortion to an image that simulates the appearance of refraction. This can be done by using the Transform node’s Distort settings to apply a predefined refraction distortion to the image, or by manually adjusting the Transform node’s settings to create a custom refraction effect. Once the Transform node has been configured to simulate the desired refraction effect, you can use the output of the Transform node to composite the distorted image over the original image, creating the illusion of refraction.
Fake refractions are a useful technique in Nuke, as they allow you to quickly and easily create the appearance of refraction without the need for complex 3D calculations. However, fake refractions are not a substitute for accurate refraction simulation, and they may not produce results that are as realistic or convincing as true refraction effects. In general, fake refractions should be used with care and discretion, and they should not be relied on as a replacement for accurate refraction simulation in 3D rendering.
«Refraction is the principle that explains how lenses work
and how light can be bent to create magnified images.» – Albert Einstein