Dial add

Description

dial_id = dial_add(image, x, y, width, height, direction_callback)
dial_id = dial_add(image, x, y, width, height, direction_callback, pressed_callback)
dial_id = dial_add(image, x, y, width, height, direction_callback, pressed_callback, released_callback)
dial_id = dial_add(image, x, y, width, height, acceleration, direction_callback)
dial_id = dial_add(image, x, y, width, height, acceleration, direction_callback, pressed_callback)
dial_id = dial_add(image, x, y, width, height, acceleration, direction_callback, pressed_callback, released_callback)

dial_add is used to add a dial on the specified location. The dial is also stored in memory for further references.

Return value

Argument	Type	Description
dial_id	ID	This value can be used for further reference. It's good practice to store this dial_id in your logic code.

Arguments

#	Argument	Type	Description
1	image	String	This is the filename of the image you would like to show on your dial. Note that this is both filename and extension. Its good practice to always use PNG format for images. JPG and BMP are also supported, but not recommended.
3	x	Number	This is the most left point of the canvas where your button should be shown.
4	y	Number	This is the most top point of the canvas where your button should be shown.
5	width	Number	The button width on the canvas. Note that the software won't preserve the aspect ratio. Scaling will be done, both stretching and cropping of the button.
6	height	Number	The button height on the canvas. Note that the software won't preserve the aspect ratio. Scaling will be done, both stretching and cropping of the button.
7	acceleration	Number	(Optional) A multiplier that will make the dial generate extra callbacks when the dial is being rotated faster. The multiplier is the maximum number of callbacks of one dial tick when this dial is being rotated at maximum speed.
8	direction_callback	Function	This function will be called when dial is being rotated. The function will give one argument, which will provide with a value telling which way the dial is being turned (1=clockwise, -1=counter-clockwise).
9	pressed_callback	Function	(Optional) This function will be called when the dial is being pressed.
10	released_callback	Function	(Optional) This function will be called when the dial is being released.

Example

function callback(direction)
  -- Direction will have the value
  --  1: When the dial is being turned clockwise
  -- -1: When the dial is being turned anti-clockwise
  print("dial has been turned into direction " .. direction)
end

-- Adds a dial, The callback function will be called when the dial is being turned
dial_id = dial_add("a.png", 100,100,100,100,callback)