Why are there individual keywords for different multiples of π

Processing Beginners
7

I was curious:

// The Processing constants are evaluated as double and then cast to float.

// PI        = (float)Math.PI;
println(HALF_PI == PI / 2);

// THIRD_PI  = (float)(Math.PI / 3.0);
println(THIRD_PI == PI / 3);

// QUARTER_PI = (float)(Math.PI / 4.0);
println(QUARTER_PI == PI / 4);

// TWO_PI    = (float)(Math.PI * 2.0);
println(TWO_PI == 2 * PI);

// TAU       = (float)(Math.PI * 2.0);
println(TAU == 2 * PI);

They were all true!

Processing generally works with float values for its sketch-level math.

In some cases, I have used double for higher precision during the intermediate calculation, then cast the final result to float.

Note:
I added Processing to the text for clarity.

Further exploration:
Processing float values: decimal output and IEEE 754 bit patterns

:)