Utility topic

Utility Module

Dart's standard math module provides trigonometric functions (sine, cosine, tangent) that operate on angles expressed in radians.

As humans often find it more intuitive to work with angles in degrees (e.g., 360° for a full circle), this module offers helper methods to simplify trigonometric calculations using degree-based inputs.

Also, the methods and functions in Bullseye2D take angles always in degree (for example the gfx.rotate or gfx.drawImage method).

Additionally, this module includes Rect, a generic class for representing rectangular areas and various extension and helpers.

Classes

Rect<T extends num> Utility
Represents a rectangle defined by a top-left corner left, top and a width and height.

Extensions

BitmaskExtension on int Utility
Provides extension methods for bitmask operations on integers.
SumListExtension on List<num> Utility
Extension on List<num> to provide utility methods for calculations.

Functions

atan2Degree(num a, num b) → double Utility
Calculates the angle in degrees for the point (b, a) using atan2(a, b).
cosDegree(num degree) → double Utility
Calculates the cosine of an angle given in degrees.
nextPowerOfTwo(int v) → int Utility
Calculates the next power of two greater than or equal to the given integer v.
sinDegree(num degree) → double Utility
Calculates the sine of an angle given in degrees.
stopEvent(Event event) → void Utility
Stops the propagation and prevents the default action of a browser Event.
tanDegree(num degree) → double Utility
Calculates the tangent of an angle given in degrees.