Blitz3D+ Command Reference

Pi

Parameters

None.

Description

A built-in constant holding the value of pi, roughly 3.141593.

Pi is a keyword rather than a function, so you write it on its own with no brackets: circumference# = 2*Pi*radius#.

It is a float constant baked in at compile time, which means expressions like 2*Pi are folded into a single number and cost nothing at runtime. Use it for circle and sphere geometry: circumference, area, the volume of a blast radius, or spacing n objects evenly around a ring.

One thing Pi is usually not needed for in Blitz3D+: converting angles. Every angle in the language - Sin, Cos, RotateEntity, TurnEntity - is already in degrees, so there is no radian conversion to do. If you are porting code from a language that uses radians, drop the 180/Pi factors rather than keeping them.

See also: Sin, Cos, ATan2, Const.

Example

; Pi Example
; ----------

; Pi is a built-in constant: 3.141592..., the ratio of a circle's
; circumference to its diameter.

Print "Pi = "+Pi

Print ""

; The classic circle formulas
radius#=5
Print "A wheel of radius "+radius+":"
Print "Circumference = 2*Pi*radius = "+(2*Pi*radius)
Print "Area = Pi*radius*radius = "+(Pi*radius*radius)

Print ""

; Blitz3D trig commands work in degrees, but if you ever need radians,
; Pi is the bridge: a full circle is 360 degrees = 2*Pi radians
Print "Full circle: 360 degrees = 2*Pi = "+(2*Pi)+" radians"

Print ""
Print "Press any key to close the example"
WaitKey

End

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