Runs a reactive program, discharging the ReflexCodeWorld constraint. This is the starting point for Reflex programs in CodeWorld.

A variant of reflexOf that includes some on-screen debugging controls. You can use this during development, but should usually switch back to reflexOf when you're done debugging.

Type class for the builder monad of a CodeWorld/Reflex app.

Gets an Event of key presses. The event value is a logical key name.

Gets an Event of key presses. The event value is a logical key name.

Gets an Event of text entered. The event value is the typed text.

Gets an event of pointer clicks. The event value is the location of the click.

Gets the Dynamic position of the pointer.

Gets a Dynamic indicator whether the pointer is held down.

Gets an Event indicating the passage of time.

Emits a given Dynamic picture to be drawn to the screen.

A design, diagram, or drawing that can be displayed and seen. In technical terms, a picture is an assignment of a color to every point of the coordinate plane. CodeWorld contains functions to create pictures from simple geometry primitives, to transform existing pictures, and to combine simpler pictures into more complex compositions.

Ultimately, a picture can be drawn on the screen using one of the CodeWorld entry points such as drawingOf.

A blank picture

A thin sequence of line segments, with these points as endpoints

A thick sequence of line segments, with given line width and endpoints

A thin polygon with these points as vertices

A thick polygon with this line width and these points as vertices

A solid polygon with these points as vertices

A smooth curve passing through these points.

A thick smooth curve with this line width, passing through these points.

A smooth closed curve passing through these points.

A thick smooth closed curve with this line width, passing through these points.

A solid smooth closed curve passing through these points.

A thin rectangle, with this width and height

A solid rectangle, with this width and height

A thick rectangle, with this line width, and width and height

A thin circle, with this radius

A solid circle, with this radius

A thick circle, with this line width and radius

A thin arc, starting and ending at these angles, with this radius

Angles are in radians.

A solid sector of a circle (i.e., a pie slice) starting and ending at these angles, with this radius

Angles are in radians.

A thick arc with this line width, starting and ending at these angles, with this radius.

Angles are in radians.

A rendering of text characters.

A rendering of text characters onto a Picture, with a specific choice of font and style.

A picture drawn entirely in this color.

A picture drawn entirely in this colour.

A picture drawn translated in these directions.

A picture scaled by these factors in the x and y directions. Scaling by a negative factoralso reflects across that axis.

A picture scaled uniformly in all directions by this scale factor. Dilating by a negative factor also reflects across the origin.

A picture rotated by this angle about the origin.

Angles are in radians.

A picture reflected across a line through the origin at this angle, in radians. For example, an angle of 0 reflects the picture vertically across the x axis, while an angle of pi / 2 reflects the picture horizontally across the y axis.

A picture clipped to a rectangle around the origin with this width and height.

An associative operation.

Binary composition of pictures.

A coordinate plane. Adding this to your pictures can help you measure distances more accurately.

Example: main = drawingOf (myPicture <> coordinatePlane) myPicture = ...

The CodeWorld logo.

A point in two dimensions. A point is written with the x coordinate first, and the y coordinate second. For example, (3, -2) is the point with x coordinate 3 a y coordinate -2.

Moves a given point by given x and y offsets

>>> translatedPoint 1 2 (10, 10)
(11.0, 12.0)
>>> translatedPoint (-1) (-2) (0, 0)
(-1.0, -2.0)

Rotates a given point by given angle, in radians

>>> rotatedPoint 45 (10, 0)
(7.071, 7.071)

Scales a given point by given x and y scaling factor. Scaling by a negative factor also reflects across that axis.

>>> scaledPoint 2 3 (10, 10)
(20, 30)

Dilates a given point by given uniform scaling factor. Dilating by a negative factor also reflects across the origin.

>>> dilatedPoint 2 (10, 10)
(20, 20)

A two-dimensional vector

The length of the given vector.

>>> vectorLength (10, 10)
14.14

The counter-clockwise angle, in radians, that a given vector make with the X-axis

>>> vectorDirection (1,0)
0.0
>>> vectorDirection (1,1)
0.7853981633974483
>>> vectorDirection (0,1)
1.5707963267948966

The sum of two vectors

The difference of two vectors

Scales a given vector by a given scalar multiplier.

>>> scaledPoint 2 (10, 10)
(20, 20)

Rotates a given vector by a given angle in radians

>>> rotatedVector pi (1.0, 0.0)
(-1.0, 1.2246467991473532e-16)
>>> rotatedVector (pi / 2) (1.0, 0.0)
(6.123233995736766e-17, 1.0)

The dot product of two vectors

An infinite list of colors.