# rgb proc

Source: https://ref.dm-lang.org/proc/rgb

### Format
- `rgb(R,G,B)`
- `rgb(R,G,B,A)`
- `rgb(x,y,z,space=*color space*)`
- `rgb(x,y,z,a,space)`


### Args
- `R,G,B`: Numbers from 0-255 corresponding to the red, green, and blue components of a color.
- `A`: Optional alpha component; 0 is transparent, 255 is opaque.
- `x,y,z`: Color components for a different color space
- `space`: [Color space](https://ref.dm-lang.org/appendix/color-space.md); defaults to `COLORSPACE_RGB`


### Returns
> A color, represented by a text string in #RRGGBB or #RRGGBBAA format

A way of representing a color to be used in conjunction with icon arithmetic, atom.color, or other effects. The colors `rgb(0,0,0)` and `rgb(255,255,255)` represent black and white, two corners of the "color cube".

```dm /rgb/
mob/proc/hurtme() // make a mob look damaged by adding red to its icon
  src.icon += rgb(20,0,0)
```

This proc returns a text string in the form used by HTML (#RRGGBB). rgb(255,0,128) for example becomes "#ff0080". If you use an alpha component, the format is #RRGGBBAA. You can use strings like this in most procs that use colors such as icon blending operations, and you can also use the short form #RGB or #RGBA. So if you know in advance that you want to use the color white, you can simply use"#fff" instead of rgb(255,255,255).

You can create colors other ways by specifying a different [color space](https://ref.dm-lang.org/appendix/color-space.md). A color space can be specified by using a [named](https://ref.dm-lang.org/proc/arguments/named.md) "space" argument, or by using a 5-argument format (you can leave the alpha value blank or null to skip it), or by using named arguments for the other components.

```dm /rgb/
// All of these lines are equivalent.
// They create (0,100,50) in HSL which is red (#ff0000).
src << rgb(0, 100, 50, space=COLORSPACE_HSL)
src << rgb(0, 100, 50, , COLORSPACE_HSL)
src << rgb(h=0, s=100, l=50)
```

Named arguments that are valid in `rgb()` are:

* `space`
* `red`
* `green`
* `blue`
* `alpha`
* `hue`
* `saturation`
* `chroma`
* `value`
* `luminance`
* `y` (HCY luminance)

With the exception of `space`, only the first letter of the argument name matters, so `r` and `red` are the same thing.

### See also
- [rgb2num proc](https://ref.dm-lang.org/proc/rgb2num.md)
- [gradient proc](https://ref.dm-lang.org/proc/gradient.md)
- [Color space](https://ref.dm-lang.org/appendix/color-space.md)
- [HTML colors](https://ref.dm-lang.org/appendix/html-colors.md)
- [color var (atom)](https://ref.dm-lang.org/atom/var/color.md)
- [Blend proc (icon)](https://ref.dm-lang.org/icon/proc/Blend.md)
- [Color matrix](https://ref.dm-lang.org/notes/color-matrix.md)
- [Color matrix filter](https://ref.dm-lang.org/notes/filters/color.md)
- [Particle effects](https://ref.dm-lang.org/notes/particles.md)