Cos
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cos( angle )
- Calculates the cosine of an angle.
- angle
-
- The angle, using a full circle range of 0.0-1.0.
The cos()
function calculates the cosine of an angle.
PICO-8 uses an input range of 0.0 to 1.0 to represent the angle, a percentage of the unit circle. Some refer to these units as "turns". For instance, 180° or π (3.14159) radians corresponds to 0.5 turns in PICO-8's representation of angles. In fact, for fans of τ (tau), it's just a matter of dropping τ from your expression.
Important: PICO-8 measures the angle in a clockwise direction on the Cartesian plane, with 0.0 to the right, 0.25 downward, and so on. This is inverted from the convention used in traditional geometry, though the inversion only affects sin()
, not cos()
.
Examples
for t=0,1,0.125 do
print('cos('..t..') = '..cos(t))
end
prints:
cos(0) = 1 cos(0.125) = 0.7071 cos(0.25) = 0 cos(0.375) = -0.7071 cos(0.5) = -1 cos(0.625) = -0.7071 cos(0.75) = 0 cos(0.875) = 0.7071 cos(1) = 1