Generators, shapes & text

Generated from project.v1.schema.json at the documented engine version. The schema checks shape only; the engine’s validation also checks ranges, limits, references and keyframe order.

Dash

A dash pattern.

Field	Type	Description
offset	Animated_float	How far into the pattern the stroke starts. Default: {"mode":"constant","value":0}
patternrequired	Animated_float[]	Alternating dash and gap lengths, as fractions of the shorter side: one to MAX_DASH_ENTRIES non-negative entries, not all zero. An odd count repeats once more to pair up.

FillRule

Which regions of a path are inside it.

• "nonzero" Where the outline winds around a point at all.
• "evenodd" Where it winds around a point an odd number of times.

Generator

The picture of a generated source.

A generated picture has the canvas's size and aspect, like a source that fills the frame at scale 1. Positions are in its normalized space, (0, 0) top-left to (1, 1) bottom-right; lengths (radii, stroke widths) are fractions of its shorter side, so the picture is the same at any render resolution. A fill or text does not change over time (a clip animates it with its transform, effects, and masks); shapes and layouts may.

One of:

type: "fill"

Paint over the whole picture.

Field	Type	Description
paintrequired	Paint	What covers the picture.

type: "shapes"

Shapes drawn from an ordered content tree, as an After Effects shape layer or a Lottie shape layer draws them. Unlike the other generators, its picture changes over time: every value in the tree may be keyframed, in the picture's time.

Field	Type	Description
itemsrequired	ShapeItem[]	The content tree, front first. See ShapeItem.

type: "text"

Text on a transparent picture, laid out and placed by its style as a caption track's cues are: its size and wrapping width fractions of the canvas, its anchor at style.position. The engine draws it with the fonts its host registered.

Field	Type	Description
style	TextStyle	How it looks and where it lies. The font size is at most MAX_TEXT_GENERATOR_FONT_SIZE. Default: {"align":"center","anchor":{"x":0.5,"y":1},"background":n…
textrequired	string	The text; \n starts a line. Non-empty, at most MAX_TEXT_CONTENT_BYTES bytes.

type: "layout"

Boxes laid out by CSS flexbox around their text and shapes. Its picture changes over time when any value in the tree is keyframed, in the picture's time. The engine lays it out with the fonts it draws with. See LayoutNode.

Field	Type	Description
rootrequired	LayoutNode	The root box: the whole picture.

GradientStop

One color of a gradient.

Field	Type	Description
colorrequired	Rgba	Color at that position.
offsetrequired	number (float)	Position along the gradient, in 0..=1, not before the previous stop.

LineCap

How an open stroke ends.

• "butt" Flat at the end point.
• "round" A half circle past the end point.
• "square" A half square past the end point.

LineJoin

How stroke segments meet at a vertex.

• "miter" Extended edges meeting at a point, up to the miter limit.
• "round" A circular arc.
• "bevel" A straight cut across the corner.

Paint

A color or gradient.

Gradients interpolate between stops premultiplied, in linear light: the engine's working space, so a gradient between two colors passes through the physical mix of them, and a stop fading to transparent does not darken its neighbour.

A color (hex or object) is read as a solid paint of it; a paint is written back tagged.

One of:

type: "solid"

One color.

Field	Type	Description
colorrequired	Rgba	The color.

type: "linear_gradient"

Colors along the line from start to end, constant across it.

Field	Type	Description
endrequired	Vec2	Where offset 1 lies. Distinct from start.
spread	Spread	What lies beyond the first and last offsets. Default: "pad"
startrequired	Vec2	Where offset 0 lies.
stopsrequired	GradientStop[]	Two to MAX_GRADIENT_STOPS stops.

type: "radial_gradient"

Colors along the radius of a circle.

Field	Type	Description
centerrequired	Vec2	Where offset 0 lies.
radiusrequired	number (float)	The distance of offset 1 from the centre, as a fraction of the picture's shorter side. Positive.
spread	Spread	What lies beyond the first and last offsets. Default: "pad"
stopsrequired	GradientStop[]	Two to MAX_GRADIENT_STOPS stops.

type: "conic_gradient"

Colors around a point: offsets 0 to 1 are one clockwise turn.

Field	Type	Description
angle_degrees	number (float)	Where offset 0 lies, in degrees clockwise from straight up. Default: 0
centerrequired	Vec2	The point the gradient turns around.
stopsrequired	GradientStop[]	Two to MAX_GRADIENT_STOPS stops.

<a href="/0.4/reference/project-schema/animation/#rgba">Rgba</a>

Path

One or more subpaths.

Field	Type	Description
subpathsrequired	Subpath[]	The subpaths, at most MAX_PATH_SUBPATHS, with at most MAX_PATH_VERTICES vertices among them.

PathVertex

A path vertex and its tangents. The segment from vertex a to vertex b is the cubic Bezier through a.point, a.point + a.out_tangent, b.point + b.in_tangent, and b.point; zero tangents make it straight.

Field	Type	Description
in_tangent	Vec2	The control point of the segment ending here, relative to point. Default: {"x":0,"y":0}
out_tangent	Vec2	The control point of the segment starting here, relative to point. Default: {"x":0,"y":0}
pointrequired	Vec2	Where the vertex lies.

PolystarKind

What kind of figure a polystar is.

• "star" Points joined by inner corners.
• "polygon" Points joined by straight sides.

ShapeGeometry

A geometry alone, as a mask's outline is.

One of:

type: "rectangle"

A rectangle, optionally with rounded corners.

Field	Type	Description
centerrequired	AnimatedPoint	Centre.
corner_radius	Animated_float	Corner radius, as a fraction of the shorter side. Non-negative; a radius past half the rectangle is capped. Default: {"mode":"constant","value":0}
rotation_degrees	Animated_float	Clockwise rotation about the centre, in degrees. Default: {"mode":"constant","value":0}
sizerequired	Animated_Vec2	Full width and height, before rotation, per axis: x a fraction of the picture's width, y of its height. Non-negative.

type: "ellipse"

An ellipse.

Field	Type	Description
centerrequired	AnimatedPoint	Centre.
rotation_degrees	Animated_float	Clockwise rotation about the centre, in degrees. Default: {"mode":"constant","value":0}
sizerequired	Animated_Vec2	Full width and height, before rotation, per axis: x a fraction of the picture's width, y of its height. Non-negative.

type: "polystar"

A regular polygon or star.

Field	Type	Description
centerrequired	AnimatedPoint	Centre.
inner_radius	Animated_float	A star's distance of its inner corners from the centre. Non-negative. Default: {"mode":"constant","value":0}
inner_roundness	Animated_float	How round a star's inner corners are, in 0..=1. Default: {"mode":"constant","value":0}
kindrequired	PolystarKind	A polygon or a star.
outer_radiusrequired	Animated_float	Distance of the points from the centre, as a fraction of the shorter side. Non-negative.
outer_roundness	Animated_float	How round the outer corners are: 0 sharp, 1 a smooth curve through them. In 0..=1. Default: {"mode":"constant","value":0}
pointsrequired	Animated_float	Number of points (corners of a polygon, tips of a star), from MIN_POLYSTAR_POINTS to MAX_POLYSTAR_POINTS. A fraction is dropped when drawn, as Lottie drops it, so an animated count changes the figure one whole point at a time.
rotation_degrees	Animated_float	Clockwise rotation about the centre, in degrees. Default: {"mode":"constant","value":0}

type: "path"

A Bezier path.

Field	Type	Description
pathrequired	Animated_Path	The path.

ShapeItem

One entry of a shapes generator's content tree.

A group is read front to back. Geometry accumulates in its group; a fill or a stroke paints the geometry listed before it in the same group, nested groups before it included; a trim cuts that geometry and replaces it. A paint listed earlier is drawn on top of one listed later, as in After Effects and Lottie.

One of:

type: "group"

Items drawn together, through one transform and opacity. Their geometry also counts as the enclosing group's, for the paints and trims after the group.

Field	Type	Description
itemsrequired	ShapeItem[]	The group's items, front first.
transform	ShapeTransform	Where the group lies, and how opaque it is. Default: {"anchor":{"mode":"constant","value":{"x":0,"y":0}},"opac…

type: "rectangle"

A rectangle, optionally with rounded corners.

Field	Type	Description
centerrequired	AnimatedPoint	Centre.
corner_radius	Animated_float	Corner radius, as a fraction of the shorter side. Non-negative; a radius past half the rectangle is capped. Default: {"mode":"constant","value":0}
rotation_degrees	Animated_float	Clockwise rotation about the centre, in degrees. Default: {"mode":"constant","value":0}
sizerequired	Animated_Vec2	Full width and height, before rotation, per axis: x a fraction of the picture's width, y of its height. Non-negative.

type: "ellipse"

An ellipse.

Field	Type	Description
centerrequired	AnimatedPoint	Centre.
rotation_degrees	Animated_float	Clockwise rotation about the centre, in degrees. Default: {"mode":"constant","value":0}
sizerequired	Animated_Vec2	Full width and height, before rotation, per axis: x a fraction of the picture's width, y of its height. Non-negative.

type: "polystar"

A regular polygon or star.

Field	Type	Description
centerrequired	AnimatedPoint	Centre.
inner_radius	Animated_float	A star's distance of its inner corners from the centre. Non-negative. Default: {"mode":"constant","value":0}
inner_roundness	Animated_float	How round a star's inner corners are, in 0..=1. Default: {"mode":"constant","value":0}
kindrequired	PolystarKind	A polygon or a star.
outer_radiusrequired	Animated_float	Distance of the points from the centre, as a fraction of the shorter side. Non-negative.
outer_roundness	Animated_float	How round the outer corners are: 0 sharp, 1 a smooth curve through them. In 0..=1. Default: {"mode":"constant","value":0}
pointsrequired	Animated_float	Number of points (corners of a polygon, tips of a star), from MIN_POLYSTAR_POINTS to MAX_POLYSTAR_POINTS. A fraction is dropped when drawn, as Lottie drops it, so an animated count changes the figure one whole point at a time.
rotation_degrees	Animated_float	Clockwise rotation about the centre, in degrees. Default: {"mode":"constant","value":0}

type: "path"

A Bezier path.

Field	Type	Description
pathrequired	Animated_Path	The path.

type: "fill"

Paints the inside of the geometry listed before it in its group, all of it as one compound path under rule. An open path is closed for it.

Field	Type	Description
opacity	Animated_float	Opacity in 0..=1. Default: {"mode":"constant","value":1}
paintrequired	Animated_Paint	What covers it.
rule	FillRule	Which regions of the compound path are inside. Default: "nonzero"

type: "stroke"

Strokes the geometry listed before it in its group.

Field	Type	Description
cap	LineCap	How open ends look. Default: "butt"
dash	Dash | null	Dashes, or a solid stroke when absent. Default: null
join	LineJoin	How segments meet. Default: "miter"
miter_limit	number (float)	Longest a miter join reaches, as a multiple of half the width, before it is beveled. At least 1. Default: 4
opacity	Animated_float	Opacity in 0..=1. Default: {"mode":"constant","value":1}
paintrequired	Animated_Paint	What covers the stroke.
widthrequired	Animated_float	Full width, as a fraction of the shorter side. Non-negative; zero draws nothing.

type: "trim"

Keeps part of the geometry listed before it in its group, by length.

Field	Type	Description
endrequired	Animated_float	Where it ends, in 0..=1. Nothing is kept unless it is after start.
mode	TrimMode	Whether the span is of all the geometry together or of each part. Default: "together"
offset	Animated_float	Turns the span is shifted by; it wraps around a closed path. Default: {"mode":"constant","value":0}
startrequired	Animated_float	Where the kept span starts, as a fraction of the length, in 0..=1.

ShapeMask

A shape that limits where a clip is visible.

Geometry is in the clip's source space, before its transform, so the mask moves with the clip: (0, 0) is the source's top-left corner and (1, 1) its bottom-right. Distances (feather, a rectangle's corner_radius, a polystar's radii) are fractions of that space's shorter side, so a mask covers the same part of the picture at any render resolution.

Field	Type	Description
feather	Animated_float	How soft the edge is. Non-negative; zero is the outline's antialiased edge. The coverage is blurred by a Gaussian of standard deviation 0.3125 * feather, which spreads its 10 to 90 percent ramp over 0.8 * feather across the outline. Default: {"mode":"constant","value":0}
fill_rule	FillRule	Which regions of the outline are inside it. Default: "nonzero"
invert	boolean	Whether the mask keeps the outside of the shape instead of its inside. Default: false
mode	MaskMode	How this mask combines with the ones before it. Default: "add"
shaperequired	ShapeGeometry	The shape's outline, as a shapes generator's geometry.

ShapeTransform

A group's placement: in pixel space, translate by position, rotate, scale, and translate by minus anchor, so anchor lands on position. The default leaves its items where they are.

Field	Type	Description
anchor	Animated_Vec2	The point of the items that is placed at position. Default: {"mode":"constant","value":{"x":0,"y":0}}
opacity	Animated_float	Opacity of the group as a whole, in 0..=1: overlapping items are composited first and faded together. Default: {"mode":"constant","value":1}
position	AnimatedPoint	Where anchor is placed. Default: {"mode":"constant","value":{"x":0,"y":0}}
rotation_degrees	Animated_float	Clockwise rotation, in degrees. Default: {"mode":"constant","value":0}
scale	Animated_Vec2	Per-axis scale; 1 leaves the items unscaled. Stroke widths scale with it. Default: {"mode":"constant","value":{"x":1,"y":1}}

Spread

What a linear or radial gradient shows outside its first and last stops.

• "pad" The end colors continue.
• "repeat" The gradient starts again.
• "reflect" The gradient runs back and forth.

Subpath

A run of vertices joined by cubic Bezier segments.

Field	Type	Description
closed	boolean	Whether a segment joins the last vertex back to the first. Default: false
verticesrequired	PathVertex[]	The vertices, in order.

TextAlign

How lines of text align within it.

• "start" Left.
• "center" Centred.
• "end" Right.

TextBackground

A box behind each line of text.

Field	Type	Description
colorrequired	Rgba	Box color.
padding	number (float)	Space between the text and the box edge, as a fraction of the font size, in [0, 2]. Default: 0

TextOutline

A band around the glyphs, drawn behind them.

Field	Type	Description
colorrequired	Rgba	Band color.
widthrequired	number (float)	Band width as a fraction of the font size, in (0, 0.5].

TextStyle

How text looks and where it lies: a caption track's cues, or a text Generator.

Sizes are resolution-independent: the font size is a fraction of the canvas's shorter side, as every other length is, the wrapping width a fraction of the canvas width, and the outline and background padding fractions of the font size. The engine draws with the fonts its host registered: those of font_family first, then the rest in their fallback order.

Field	Type	Description
align	TextAlign	How lines align within the text. Default: "center"
anchor	Vec2	The point of the text, background included, placed at position: (0.5, 1) is its bottom centre. Default: {"x":0.5,"y":1}
background	TextBackground | null	A box behind each line. Default: null
color	Rgba	Text color. Default: {"alpha":1,"blue":1,"green":1,"red":1}
font_family	string | null	The family the text draws in, as the font's own name table gives it (typographic family, else family), matched without regard to ASCII case. Glyphs its fonts lack, and a family no registered font has, draw from the other fonts in fallback order. None draws from the fallback order alone. Non-empty, at most MAX_FONT_FAMILY_BYTES bytes.
font_size	number (float)	Font size as a fraction of the canvas's shorter side: positive, at most MAX_CAPTION_FONT_SIZE on a caption track and MAX_TEXT_GENERATOR_FONT_SIZE in a text generator. Default: 0.05
font_weight	integer (uint16)	The weight, in [1, 1000], a family's faces are matched by, as CSS Fonts 4 matches font-weight; a variable face draws at it, clamped to its wght axis. No face is emboldened: a weight the family lacks draws its nearest face. Default: 400
letter_spacing	number (float)	Space after each character, as a fraction of the font size, in [-0.5, 1], as CSS letter-spacing adds it: none after a line's last character, and none after a character of a cursive script (Arabic, say), whose joins it would break. Not zero, it turns optional ligatures off. Default: 0
line_height	number (float)	Baseline-to-baseline distance in font sizes, in [0.5, 3]. Each line's em box, 0.8 of a font size above its baseline and 0.2 below, is centred in its line when the line is taller than an em. Default: 1.2
max_width	number (float)	Width text wraps at, as a fraction of the canvas width, in (0, 1]. Default: 0.9
outline	TextOutline | null	A band around the glyphs. Default: null
position	Vec2	Where on the canvas the text's anchor lies, (0, 0) top-left to (1, 1) bottom-right. Default: {"x":0.5,"y":0.92}

TrimMode

What a trim measures.

• "together" One span over the length of every subpath end to end, in order.
• "individually" A span of each subpath alone.