Design Format
Design
The root Polotno design document – width, height, fonts, pages and other top-level metadata. This is what `store.toJSON()` produces and `store.loadJSON()` accepts.
Type Information
Base Type: object
Properties
| Property | Type | Description |
|---|---|---|
schemaVersion | number | Schema version for compatibility / migration. A design without it counts as version 0, the oldest format, and is migrated on load, so write the current version in new JSON. |
width | number | Canvas width in pixels. |
height | number | Canvas height in pixels. |
unit | "px" | "pt" | "mm" | "cm" | "in" | Unit type for print measurements. |
dpi | number | Dots per inch for print calculations. |
custom | unknown | Custom data attached to the design. |
fonts | Array<Font> | Fonts used in the design. |
pages | Array<Page> | Pages in the design. |
audios | Array<Audio> | Audio tracks in the design. |
JSON Schema
{
"type": "object",
"properties": {
"schemaVersion": {
"default": 5,
"description": "Schema version for compatibility / migration. A design without it counts as version 0, the oldest format, and is migrated on load, so write the current version in new JSON.",
"type": "number"
},
"width": {
"default": 1080,
"description": "Canvas width in pixels.",
"type": "number"
},
"height": {
"default": 1080,
"description": "Canvas height in pixels.",
"type": "number"
},
"unit": {
"default": "px",
"description": "Unit type for print measurements.",
"type": "string",
"enum": [
"px",
"pt",
"mm",
"cm",
"in"
]
},
"dpi": {
"default": 72,
"description": "Dots per inch for print calculations.",
"type": "number"
},
"custom": {
"description": "Custom data attached to the design."
},
"fonts": {
"default": [],
"description": "Fonts used in the design.",
"type": "array",
"items": {
"type": "object",
"properties": {
"fontFamily": {
"type": "string",
"description": "Font family name."
},
"url": {
"default": "",
"description": "URL to load the font from (single-variant fonts).",
"type": "string"
},
"styles": {
"description": "Per-weight/style variants for multi-variant families.",
"type": "array",
"items": {
"type": "object",
"properties": {
"src": {
"type": "string",
"description": "Font source, typically in CSS url() form."
},
"fontStyle": {
"type": "string"
},
"fontWeight": {
"type": "string"
}
},
"required": [
"src"
]
}
}
},
"required": [
"fontFamily"
]
}
},
"pages": {
"default": [],
"description": "Pages in the design.",
"type": "array",
"items": {
"type": "object",
"properties": {
"id": {
"type": "string",
"description": "Unique identifier for the page."
},
"width": {
"default": "auto",
"description": "Page width in pixels or 'auto'.",
"anyOf": [
{
"type": "number"
},
{
"type": "string",
"const": "auto"
}
]
},
"height": {
"default": "auto",
"description": "Page height in pixels or 'auto'.",
"anyOf": [
{
"type": "number"
},
{
"type": "string",
"const": "auto"
}
]
},
"background": {
"default": "white",
"description": "Background color or image.",
"type": "string"
},
"bleed": {
"default": 0,
"description": "Bleed area in pixels for print (all sides; base value for per-side overrides).",
"type": "number"
},
"bleedTop": {
"description": "Per-side bleed override (top), in pixels. Inherits `bleed` when omitted.",
"type": "number"
},
"bleedRight": {
"description": "Per-side bleed override (right), in pixels. Inherits `bleed` when omitted.",
"type": "number"
},
"bleedBottom": {
"description": "Per-side bleed override (bottom), in pixels. Inherits `bleed` when omitted.",
"type": "number"
},
"bleedLeft": {
"description": "Per-side bleed override (left), in pixels. Inherits `bleed` when omitted.",
"type": "number"
},
"custom": {},
"duration": {
"default": 5000,
"description": "Page duration in milliseconds.",
"type": "number"
},
"children": {
"default": [],
"description": "Elements on this page.",
"type": "array",
"items": {
"$ref": "#/$defs/__schema0"
}
}
},
"required": [
"id"
]
}
},
"audios": {
"default": [],
"description": "Audio tracks in the design.",
"type": "array",
"items": {
"type": "object",
"properties": {
"id": {
"type": "string",
"description": "Unique identifier for the audio track."
},
"name": {
"default": "",
"description": "Display name shown on the timeline.",
"type": "string"
},
"src": {
"default": "",
"description": "URL or data URI of the audio file.",
"type": "string"
},
"duration": {
"default": 0,
"description": "Duration in milliseconds.",
"type": "number"
},
"startTime": {
"default": 0,
"description": "Start offset (0-1).",
"type": "number"
},
"endTime": {
"default": 1,
"description": "End offset (0-1).",
"type": "number"
},
"volume": {
"default": 1,
"description": "Volume level (0-1).",
"type": "number"
},
"delay": {
"default": 0,
"description": "Delay before playing, in milliseconds.",
"type": "number"
},
"speed": {
"default": 1,
"description": "Playback speed multiplier (1 = normal).",
"type": "number"
},
"custom": {}
},
"required": [
"id"
]
}
}
}
}