Language conventions

Visript is the language; .viscript is its standard source extension.

Names and calls

Use snake_case for functions, parameters, properties and local variables, and $UPPER_SNAKE_CASE for system values. Calls use named arguments, for example draw::circle(x: 100, y: 100, radius: 30). User-defined function parameters need defaults; some built-in parameters are required.

Namespaces group related operations. See the standard library map.

Units and coordinates

2D uses pixels with the origin at the top left; X increases right and Y down. 3D uses world coordinates and a camera. Each function documents its pivot and coordinate system. Use full dimension names such as width, height and depth.

Angles use rad or deg, or a descriptive name such as rotation_y_deg. Supply only one unit for each angle. Trigonometric inputs use rad; inverse trigonometric functions return radians. HSL hue uses normalized turns.

Colour and strokes

Colour constructors use a for alpha: 0 is transparent, 1 is opaque, and the default is 1. Replace the old transparent argument with a: 1.0 - (old_value). Shape opacity and filter amounts are separate controls. Outline thickness uses stroke_width.

Integers and floats

Counts and array write indices require integers where specified. Rounding a float does not change its type: math::floor returns a float, while integer division (\) returns an integer. See Control Flow.

Input state and events

input::<device>::state reads persistent state. input::<device>::event reads the current matching event. Getters use get_ for values and is_ for booleans. Event values are available only while handling their event. See Input Detection.