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color() function

Introduction

Codea's built-in reference documents most of the color() function. The function returns a userdata value that is a vector in four dimensions, used to represent red, green, blue and alpha (opacity) values.

Setting and getting individual coordinates

Indexing can be used to set and get individual co-ordinates, either by (r, g, b, a) or by ordinal number or by other letters - (x, y, z, w), as summarised in the table below:

Co-ordinate	Index scheme	Index scheme	Index scheme
First	`c1[1]`	`c1.x` or `c1["x"]`	`c1.r` or `c1["r"]`
Second	`c1[2]`	`c1.y` or `c1["y"]`	`c1.g` or `c1["g"]`
Third	`c1[3]`	`c1.z` or `c1["z"]`	`c1.b` or `c1["b"]`
Fourth	`c1[4]`	`c1.w` or `c1["w"]`	`c1.a` or `c1["a"]`

Each co-ordinate can be set to any number value (and is not constrained, for example, to the range 0 to 255). The graphical color picking in Codea's Editor tolerates this.

Operators

From version 1.4.3 of Codea, like vec4(), the result of the color() function supports operators, such as the == operator. For example:

print(color(0, 0, 0, 0) == color(0, 0, 0, 0)) -- Output is 'true'
print(vec4(0, 0, 0, 0) == vec4(0, 0, 0, 0))   -- Output is 'true'

Functions

The result supports tostring() to produce nicely-formatted output. Consequently, print() also generates nicely-formatted output.