Parameter

Parameters are objects in the block's parameters array.

Common Properties

`datum`

Type	`object`

See the Datum section.

`defaultValue`

Type	`string`

The default value of the parameter, as shown in the mobile app editor when a parameter is left empty.

"defaultValue": "50"

`key`

Type	`string`

The label for the parameter.

This value can be modified to change the parameter's display name in the editor, unlike other attributes of a block which are hardcoded to its block type. (This is used to label some blocks which don't have hardcoded block names, such as Wait Til Timestamp.) However, key modifications are not guaranteed to work with certain block types, such as Set Invisibility.^{[needs verification]}

"key": "percent"

`type`

Type	`number`

A magic number that corresponds to the parameter's type and behavior.^{[needs verification]}

For a full list of possible values, see Viewing Types.

"type": 57

`value`

Type	`string`

The parameter's value.

"value": "100"

`variable`

Type	`string`

Optional. An ID used in rules to reference event parameters. Overrides the value parameter with its contents.

If datum does not exist, then the player will attempt to find the following types with this reference:

Variable (If this isn't found, the player will try to find a...)
Trait
Event parameter

Example missing.

Datum

The datum property determines the parameter's data contents.

Each datum exclusively contains one of the following (see each respective page for more information):

An operator block
- Includes HSB, RGB and randomized color operators
A trait
variable property with a variable reference
An image for the Set Image block^{[needs elaboration]}

Player Priority

The player checks datum objects in the following order:^{[needs verification]}

Images within Set Image blocks
Variable references
Traits and blocks

Math Operator Blocks

Here is a Move Forward block with an addition (+) operator block as its datum:

Move forward by negative one, plus ten

{
	"block_class": "method",
	"type": 23,
	"description": "Move Forward",
	"parameters": [{
		"value": "100",
		"defaultValue": "100",
		"key": "",
		"type": 57, // MultiPurposeNumberDefault: parameter
		"datum": {
			"keyboardName": "Add",
			"block_class": "operator",
			"type": 4000, // MathOperatorAdd: block
			"description": "+",
			"params": [{
				"defaultValue": "2",
				"value": "-1",
				"key": "",
				"type": 57
			}, {
				"defaultValue": "3",
				"value": "10",
				"key": "+",
				"type": 57
			}]
		}
	}]
}

Math operator datums are commonly nested:

Change X by negative one, plus a random number between ten and fifty

{
	"block_class": "method",
	"description": "Change X by",
	"type": 27,
	"parameters": [{
		"value": "100",
		"defaultValue": "100",
		"key": "",
		"type": 57, // MultiPurposeNumberDefault: parameter
		"datum": {
			"keyboardName": "Add",
			"block_class": "operator",
			"type": 4000, // MathOperatorAdd: block
			"description": "+",
			"params": [{
				"defaultValue": "2",
				"value": "-1",
				"key": "",
				"type": 57 // MultiPurposeNumberDefault: parameter
			}, {
				"defaultValue": "3",
				"value": "3",
				"key": "+",
				"type": 57, // MultiPurposeNumberDefault: parameter
				"datum": {
					"block_class": "operator",
					"type": 4004, // MathOperatorRandom: parameter
					"description": "Random",
					"params": [{
						"defaultValue": "1",
						"value": "10",
						"key": "",
						"type": 45 // RandomLow: parameter
					}, {
						"defaultValue": "100",
						"value": "50",
						"key": "to",
						"type": 46 // RandomHigh: parameter
					}]
				}
			}]
		}
	}]
}

Color Operator Blocks

Plain colors

Colors picked from the editor's color palette do not use datums.

note

The value property can be edited. Changes are reflected in the editor view accordingly.

However, if a datum is added, this value will be overridden.

Set trail color to pure black

{
	"block_class": "method",
	"description": "Set Trail Color",
	"type": 32,
	"parameters": [{
		"defaultValue": "HSB(288,57,43)",
		"value": "HSB(0,0,0)",
		"key": "to",
		"type": 44 // LineColor: parameter
	}]
}

Random colors

Set trail color to a random one

{
	"block_class": "method",
	"description": "Set Trail Color",
	"type": 32,
	"parameters": [{
		"defaultValue": "HSB(288,57,43)",
		"value": "HSB(353,96,83)", // plain color value is overridden by datum
		"key": "to",
		"type": 44, // LineColor: parameter
		"datum": {
			"type": 5000, // ColorOperatorRandom: block
			"block_class": "operator",
			"description": "Random"
		}
	}]
}

RGB colors

Set RGB color to magenta

{
	"block_class": "method",
	"description": "Set Trail Color",
	"type": 32,
	"parameters": [{
		"defaultValue": "HSB(288,57,43)",
		"value": "HSB(288,57,43)", // plain color value is overridden by datum
		"key": "to",
		"type": 44, // LineColor: parameter
		"datum": {
			"type": 5001, // ColorOperatorRGB: block
			"block_class": "operator",
			"description": "RGB",
			"params": [{
				"value": "255",
				"defaultValue": "34",
				"key": "R",
				"type": 57 // MultiPurposeNumberDefault: parameter
			}, {
				"value": "0",
				"defaultValue": "246",
				"key": "G",
				"type": 57 // MultiPurposeNumberDefault: parameter
			}, {
				"value": "255",
				"defaultValue": "217",
				"key": "B",
				"type": 57 // MultiPurposeNumberDefault: parameter
			}]
		}
	}]
}

HSB colors

Set HSB color to magenta

{
	"block_class": "method",
	"description": "Set Trail Color",
	"type": 32,
	"parameters": [{
		"defaultValue": "HSB(288,57,43)",
		"value": "HSB(288,57,43)", // plain color value is overridden by datum
		"key": "to",
		"type": 44, // LineColor: parameter
		"datum": {
			"type": 5002, // ColorOperatorHSB: block
			"block_class": "operator",
			"description": "HSB",
			"params": [{
				"value": "172",
				"defaultValue": "172",
				"key": "H",
				"type": 57 // MultiPurposeNumberDefault: parameter
			}, {
				"value": "86",
				"defaultValue": "86",
				"key": "S",
				"type": 57 // MultiPurposeNumberDefault: parameter
			}, {
				"value": "96",
				"defaultValue": "96",
				"key": "B",
				"type": 57 // MultiPurposeNumberDefault: parameter
			}]
		}
	}]
}

Variable References

Local variables

Local variables are fully scoped within the datum, bypassing the need for a variable reference:

Set local variable to 10

{
	"block_class": "method",
	"type": 45, // SetVariable: block
	"description": "Set",
	"parameters": [{
		"value": "",
		"defaultValue": "",
		"key": "",
		"type": 47, // Variable: parameter
		"datum": {
			"type": 8009, // Scoped: block
			"description": "Local Variable",
			"name": "localVar"
		}
	}, {
		"value": "10",
		"defaultValue": "10",
		"key": "to",
		"type": 48 // VariableValue: parameter
	}]
}

Other variables

Object, Self and Global variables store a reference to an external variable.

The object property is only included in object variables. It is a reference to the object the variable is stored in.

Set heart object variable to 30

{
	"block_class": "method",
	"type": 45, // SetVariable: block
	"description": "Set",
	"parameters": [{
		"value": "",
		"defaultValue": "",
		"key": "",
		"type": 47, // Variable: parameter
		"datum": {
			"variable": "9A4C3DCD-5C4A-B35C-6C32-0D519B578B9E",
			"description": "Variable",
			// The variable type here can be the following:
			// 8000, Object: block
			// 8003, Game: block
			// 8004, Self: block
			"type": 8000, // Object: block
			"object": "83217D2E-F034-4457-3BCB-48B715AFA3AD"
		}
	}, {
		"value": "30",
		"defaultValue": "10",
		"key": "to",
		"type": 48 // VariableValue: parameter
	}]
}

Traits

Coming soon!

Nested Datums

The following example is the JSON structure for this block, which includes a variety of datums:

Turn degrees block, with the parameter 90 plus the sine of variable gameVar

{
	"block_class": "method",
	"type": 24,
	"description": "Turn",
	"parameters": [{
		"value": "90",
		"defaultValue": "90",
		"key": "degrees",
		"type": 57,
		"datum": {
			"keyboardName": "Add",
			"block_class": "operator",
			"type": 4000,
			"description": "+",
			"params": [{
				"defaultValue": "2",
				"value": "90",
				"key": "",
				"type": 57
			}, {
				"defaultValue": "3",
				"value": "3",
				"key": "+",
				"type": 57,
				"datum": {
					"keyboardName": "Sine",
					"block_class": "operator",
					"type": 4007,
					"description": "Sin",
					"params": [{
						"defaultValue": "45",
						"value": "3",
						"key": "",
						"type": 57,
						"datum": {
							"variable": "D9D0EA2D-C656-7C7A-8843-EF5716D2909C",
							"description": "Variable",
							"type": 8003
						}
					}]
				}
			}]
		}
	}]
}

Common Properties​

datum​

defaultValue​

key​

type​

value​

variable​

Datum​

Player Priority​

Math Operator Blocks​

Color Operator Blocks​

Plain colors​

Random colors​

RGB colors​

HSB colors​

Variable References​

Local variables​

Other variables​

Traits​

Nested Datums​