Rotary

Create a rotary knob the user can turn.

Rotaries are drawn between a starting point (x1, y1) and an ending point (x2, y2). Its lowest and highest values sit at the bottom, and it rotates around arcWidth degrees in between.

Creating a Rotary

You can create a Rotary using the following functions:

Rotary(x1, y1, x2, y2)

Rotary(x1, y1, x2, y2, minValue, maxValue, startValue, action, foregroundColor, backgroundColor, outlineColor, thickness, arcWidth, rotation, visibility)

Parameter	Type	Default	Description
x1	int or float	required	The horizontal position of the top-left corner, in pixels.
y1	int or float	required	The vertical position of the top-left corner, in pixels.
x2	int or float	required	The horizontal position of the bottom-right corner, in pixels.
y2	int or float	required	The vertical position of the bottom-right corner, in pixels.
minValue	int	0	The smallest value the knob can take.
maxValue	int	999	The largest value the knob can take.
startValue	int or float	None	The knob's starting value. Defaults to halfway between minValue and maxValue.
action	function	None	The function to call when the knob turns; it receives the new value.
foregroundColor	Color	Color.RED	The color of the level shown by the knob.
backgroundColor	Color	Color.BLACK	The color behind the knob.
outlineColor	Color	Color.BLUE	The outline color.
thickness	int	3	The outline thickness, in pixels.
arcWidth	int or float	300	How far the knob turns from lowest to highest, in degrees. A typical value is 300.
rotation	int or float	0	How far to turn the whole control, in degrees, counter-clockwise.
visibility	int	100	How visible the knob is, from 0 (invisible) to 100 (fully visible).

For example,

simpleRotary.py

# simpleRotary.py
# Creates a Rotary and prints its value when it changes.

from gui import *

d = Display()

# function to specify what happens when knob is turned
def printValue(value):
   print(value)   # replace this with whatever needs to happen

knob = Rotary(5, 5, 100, 100, -100, 100, 0, printValue, Color.WHITE, Color.BLACK, Color.RED, 1, 300)

d.add(knob)

Once created, you can add it to a Display using the Display's add() function.

Functions

Once a Rotary rotary has been created, the following functions are available:

Function	Description
rotary.setValue(newValue)	Set the object's value.
rotary.getValue()	Return the object's current value.

Position

Function	Description
rotary.getPosition()	Return the object's position, the top-left corner of its bounding box.
rotary.getX()	Return the object's horizontal position.
rotary.getY()	Return the object's vertical position.
rotary.getCenter()	Return the object's center point.
rotary.getCenterX()	Return the object's horizontal center.
rotary.getCenterY()	Return the object's vertical center.
rotary.setPosition(x, y)	Move the object so the top-left corner of its bounding box sits at the given point.
rotary.setX(x)	Set the object's horizontal position.
rotary.setY(y)	Set the object's vertical position.
rotary.setCenter(x, y)	Move the object so its center sits at the given point.
rotary.setCenterX(x)	Set the object's horizontal center.
rotary.setCenterY(y)	Set the object's vertical center.
rotary.move(x, y)	Move the object to a new position.

Size

Function	Description
rotary.getSize()	Return the object's width and height.
rotary.getWidth()	Return the object's width.
rotary.getHeight()	Return the object's height.
rotary.setSize(width, height)	Set the object's width and height.
rotary.setWidth(width)	Set the object's width.
rotary.setHeight(height)	Set the object's height.

Rotation

Function	Description
rotary.getRotation()	Return how far the object is turned.
rotary.setRotation(rotation)	Turn the object to a given angle.
rotary.rotate(angle)	Turn the object by an additional angle.

Visibility

Function	Description
rotary.getVisibility()	Return how visible the object is.
rotary.setVisibility(visibility)	Set how visible the object is.

Information

Function	Description
rotary.getEndpoints()	Return the object's four corners.
rotary.getBoundingBox()	Return the smallest upright box that surrounds the object.
rotary.getGroup()	Return the Group this object belongs to.
rotary.getDisplay()	Return the Display this object is on.
rotary.setToolTipText()	Set the hover text shown over the object.

Hit Testing

Function	Description
rotary.contains(x, y)	Report whether a point lies inside the object.
rotary.intersects(other)	Report whether this object overlaps another.
rotary.encloses(other)	Report whether this object completely contains another.

Events

Function	Description
rotary.onMouseClick(action)	Set up a function to call when the mouse is clicked on this object.
rotary.onMouseDown(action)	Set up a function to call when the mouse rotary is pressed on this object.
rotary.onMouseUp(action)	Set up a function to call when the mouse rotary is released over this object.
rotary.onMouseMove(action)	Set up a function to call when the mouse moves over this object.
rotary.onMouseDrag(action)	Set up a function to call when the mouse is dragged over this object.
rotary.onMouseEnter(action)	Set up a function to call when the mouse moves onto this object.
rotary.onMouseExit(action)	Set up a function to call when the mouse moves off this object.
rotary.onKeyType(action)	Set up a function to call when a key is typed (pressed and released).
rotary.onKeyDown(action)	Set up a function to call when a key is pressed down.
rotary.onKeyUp(action)	Set up a function to call when a key is released.