GameMaker Studio 2 has a comprehensive selection of functions to manipulate the colour and alpha of what is drawn on the screen (for blending images using special blend modes and other PGU specific functions see the section on the GPU Control. Using these functions you can separate colours into their component parts, create new colours and manipulate the draw alpha to change how different things in your game are drawn together. Apart from these functions, there are also a number of constants that can be used as base colours in these (and other) functions:
Note that you can also create colours from their hexadecimal value using the "$" symbol beforehand, and these values can also be used in the colour functions to get component hues or for mixing, etc... The hexadecimal value for these colours is split into three parts with the format Blue / Green / Red so, for example, to define a purple colour you could use:
col = $983c95
Where 98 is the blue component, 3c is the green component and 95 is the red component.
The following functions can be used to get the component hues, compound hue, saturation and luminosity of a selected colour as well as the alpha and other properties:
These functions can be used to create colours from raw input values for colour components: