Transparency Dithering

Dithering, specifically transparency dithering is an effect to "emulate" transparency blending without having to actually carry the cost of blending.

Applications

Transparency dithering is used

When using the punch through render layer
To make otherwise opaque models see-through when they are covering something the game wants you to see (like the player character)

Types of dithering

Pattern Dithering

A carefully crafted dithering texture is used to achieve dithering with a mostly consistent density of discarded pixels.


The dithering texture used in Shadow Generations	A linear gradient	The linear gradient with pattern dithering applied	A circle slowly dithering out

This method of dithering is implemented in every shader that does not implement any other dithering method.*

*only confirmed for Shadow Generations so far

Noise Dithering

A white-noise texture is used for random looking dithering.


The red channel of the "blue_noise_256x" texture from Shadow Generations, which is used for noise dithering	A linear gradient	The linear gradient with noise dithering applied	The linear gradient with noise dithering applied, animated (a 4-frame loop)

In Shadow Generations noise dithering is usually used in shaders with "dither" in their name, like Common_dither_dpn. Those shaders also support animating the dithering, as shown in the table, but it is currently unknown how to enable the animation.

Gallery

A GUN bot made see-through using dithering to make Shadow Visible in Shadow Generations
A punch-through model in SXSG using the Common_dither_dpn shader with a clip threshold of 0 and a transparency of 0.3