This is a simple port of https://github.com/sug0/go-glitch to rust.

You can think of the image as a functor that you map an expression to, for each pixel's component colors, returning a new one. The allowed operators are:

• t a pixel made up of a random color component from the neighboring 16 pixels
• g a pixel made up of a random color component from random locations in the image
• r{Num} a pixel made up of a random color component from the neighboring Num pixels
• R{Num} the red color component defined by Num (i.e. R255 is the same as R)
• G{Num} the green color component defined by Num (i.e. G255 is the same as G)
• B{Num} the blue color component defined by Num (i.e. B255 is the same as B)
• i inverts the color component
• b{Num} the brightness of the color component defined by Num (i.e. b255 is the same as b)

• + plus
• - minus
• * multiplication
• / division
• % modulo
• # power of operator
• & bit and
• | bit or
• : bit and not
• ^ bit xor
• < bit left shift
• > bit right shift
• ? returns 255 if left side is greater otherwise 0
• @ attributes a weight in the range [0, 255] to the value on the left

The expressions are made up of operators, numbers, parenthesis, and a set of parameters:

• c the current value of each pixel component color
• b the blurred version of c
• h the horizontally flipped version of c
• v the vertically flipped version of c
• d the diagonally flipped version of c
• Y the luminosity, or grayscale component of each pixel
• N a noise pixel (i.e. a pixel where each component is a random value)
• R the red color (i.e. rgb(255, 0, 0))
• G the green color (i.e. rgb(0, 255, 0))
• B the blue color (i.e. rgb(0, 0, 255))
• s the value of each pixel's last saved evaluated expression
• r a pixel made up of a random color component from the neighboring 8 pixels
• e the difference of all pixels in a box, creating an edge-like effect
• x the current x coordinate being evaluated normalized in the range [0, 255]
• y the current y coordinate being evaluated normalized in the range [0, 255]
• H the highest valued color component in the neighboring 8 pixels
• L the lowest valued color component in the neighboring 8 pixels

• 128 & (c - ((c - 150 + s) > 5 < s))
• (c & (c ^ 55)) + 25
• 128 & (c + 255) : (s ^ (c ^ 255)) + 25