A drawing canvas containing an ordered sequence of shapes
Properties
The canvas background as a CSS color string; omitted or empty for transparent
The AT-URI of this block record
The canvas height in pixels
The shapes in the drawing as a sequence of shape block ids in z-order (later = on top)
The canvas width in pixels
View raw schema
{
"type": "object",
"required": [
"blockId"
],
"properties": {
"title": {
"ref": "page.corvus.core#sequence",
"type": "ref",
"description": "The name of the drawing"
},
"width": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "The canvas width in pixels"
},
"height": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "The canvas height in pixels"
},
"shapes": {
"ref": "page.corvus.core#sequence",
"type": "ref",
"description": "The shapes in the drawing as a sequence of shape block ids in z-order (later = on top)"
},
"blockId": {
"type": "string",
"format": "at-uri",
"description": "The AT-URI of this block record"
},
"background": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "The canvas background as a CSS color string; omitted or empty for transparent"
}
},
"description": "A drawing canvas containing an ordered sequence of shapes"
}
An ellipse or circle (set rx == ry for a circle)
Properties
The AT-URI of this block record
Center X coordinate in pixels
Center Y coordinate in pixels
Fill style as a CSS color string; omitted or empty for no fill
Opacity from 0 to 1 (defaults to 1)
Rotation in radians around (cx, cy) (defaults to 0)
Stroke style as a CSS color string; omitted or empty for no stroke
Stroke width in pixels (defaults to 1)
View raw schema
{
"type": "object",
"required": [
"blockId"
],
"properties": {
"cx": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Center X coordinate in pixels"
},
"cy": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Center Y coordinate in pixels"
},
"rx": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "X radius in pixels"
},
"ry": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Y radius in pixels"
},
"fill": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Fill style as a CSS color string; omitted or empty for no fill"
},
"stroke": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Stroke style as a CSS color string; omitted or empty for no stroke"
},
"blockId": {
"type": "string",
"format": "at-uri",
"description": "The AT-URI of this block record"
},
"opacity": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Opacity from 0 to 1 (defaults to 1)"
},
"rotation": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Rotation in radians around (cx, cy) (defaults to 0)"
},
"strokeWidth": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Stroke width in pixels (defaults to 1)"
}
},
"description": "An ellipse or circle (set rx == ry for a circle)"
}
A named collection of shape block ids — a tag that lets a set of shapes be referred to together (selected, named, toggled). Membership is order-independent; z-order comes from #main.shapes
Properties
The AT-URI of this block record
The display name of the group
The set of member shape block ids
View raw schema
{
"type": "object",
"required": [
"blockId"
],
"properties": {
"name": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "The display name of the group"
},
"shapes": {
"ref": "page.corvus.core#set",
"type": "ref",
"description": "The set of member shape block ids"
},
"blockId": {
"type": "string",
"format": "at-uri",
"description": "The AT-URI of this block record"
}
},
"description": "A named collection of shape block ids — a tag that lets a set of shapes be referred to together (selected, named, toggled). Membership is order-independent; z-order comes from #main.shapes"
}
A placed image — positions and sizes a page.corvus.contentBlocks#image within the drawing. The image asset itself lives in the referenced block (its blob, alt text, and aspect ratio); this variant only carries the placement
Properties
The AT-URI of this block record
Register whose value is the at-uri of the page.corvus.contentBlocks#image block to render
Opacity from 0 to 1 (defaults to 1)
Rotation in radians around the image's center (defaults to 0)
Top-left X coordinate in pixels
Top-left Y coordinate in pixels
View raw schema
{
"type": "object",
"required": [
"blockId"
],
"properties": {
"x": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Top-left X coordinate in pixels"
},
"y": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Top-left Y coordinate in pixels"
},
"image": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Register whose value is the at-uri of the page.corvus.contentBlocks#image block to render"
},
"width": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Width in pixels"
},
"height": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Height in pixels"
},
"blockId": {
"type": "string",
"format": "at-uri",
"description": "The AT-URI of this block record"
},
"opacity": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Opacity from 0 to 1 (defaults to 1)"
},
"rotation": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Rotation in radians around the image's center (defaults to 0)"
}
},
"description": "A placed image — positions and sizes a page.corvus.contentBlocks#image within the drawing. The image asset itself lives in the referenced block (its blob, alt text, and aspect ratio); this variant only carries the placement"
}
A vector path — a sequence of commands that map directly to canvas path operations. Commands are inline values in the sequence and have no stable identity across edits (editing a command means deleting and re-inserting it). Use #stroke instead for freehand brush traces.
Properties
The AT-URI of this block record
The path commands as an RGA sequence of #pathCommand objects
Fill style as a CSS color string; omitted or empty for no fill
Opacity from 0 to 1 (defaults to 1)
Rotation in radians applied around (x, y) at render time (defaults to 0)
Stroke style as a CSS color string; omitted or empty for no stroke
Stroke width in pixels (defaults to 1)
Origin X offset applied to the path at render time (defaults to 0)
Origin Y offset applied to the path at render time (defaults to 0)
View raw schema
{
"type": "object",
"required": [
"blockId"
],
"properties": {
"x": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Origin X offset applied to the path at render time (defaults to 0)"
},
"y": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Origin Y offset applied to the path at render time (defaults to 0)"
},
"fill": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Fill style as a CSS color string; omitted or empty for no fill"
},
"stroke": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Stroke style as a CSS color string; omitted or empty for no stroke"
},
"blockId": {
"type": "string",
"format": "at-uri",
"description": "The AT-URI of this block record"
},
"opacity": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Opacity from 0 to 1 (defaults to 1)"
},
"commands": {
"ref": "page.corvus.core#sequence",
"type": "ref",
"description": "The path commands as an RGA sequence of #pathCommand objects"
},
"rotation": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Rotation in radians applied around (x, y) at render time (defaults to 0)"
},
"strokeWidth": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Stroke width in pixels (defaults to 1)"
}
},
"description": "A vector path — a sequence of commands that map directly to canvas path operations. Commands are inline values in the sequence and have no stable identity across edits (editing a command means deleting and re-inserting it). Use #stroke instead for freehand brush traces."
}
A single path command. Used inline as a value in a #path.commands sequence — NOT its own block, NOT addressable, no stable identity across edits
Properties
Coordinate arguments; interpretation depends on op. Angles for the A command are encoded in milliradians (0 to 2π × 1000) so they fit an integer
M=moveTo (x,y); L=lineTo (x,y); C=bezierCurveTo (cp1x,cp1y,cp2x,cp2y,x,y); Q=quadraticCurveTo (cpx,cpy,x,y); A=arc (cx,cy,r,startAngle,endAngle,counterclockwise); Z=closePath (no coords)
Known values: M, L, C, Q, A, Z
View raw schema
{
"type": "object",
"required": [
"op"
],
"properties": {
"op": {
"type": "string",
"description": "M=moveTo (x,y); L=lineTo (x,y); C=bezierCurveTo (cp1x,cp1y,cp2x,cp2y,x,y); Q=quadraticCurveTo (cpx,cpy,x,y); A=arc (cx,cy,r,startAngle,endAngle,counterclockwise); Z=closePath (no coords)",
"knownValues": [
"M",
"L",
"C",
"Q",
"A",
"Z"
]
},
"coords": {
"type": "array",
"items": {
"type": "integer"
},
"description": "Coordinate arguments; interpretation depends on op. Angles for the A command are encoded in milliradians (0 to 2π × 1000) so they fit an integer"
}
},
"description": "A single path command. Used inline as a value in a #path.commands sequence — NOT its own block, NOT addressable, no stable identity across edits"
}
An axis-aligned rectangle, optionally rotated around its center
Properties
The AT-URI of this block record
Corner radius in pixels (defaults to 0)
Fill style as a CSS color string; omitted or empty for no fill
Opacity from 0 to 1 (defaults to 1)
Rotation in radians around the rect's center (defaults to 0)
Stroke style as a CSS color string; omitted or empty for no stroke
Stroke width in pixels (defaults to 1)
Top-left X coordinate in pixels
Top-left Y coordinate in pixels
View raw schema
{
"type": "object",
"required": [
"blockId"
],
"properties": {
"x": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Top-left X coordinate in pixels"
},
"y": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Top-left Y coordinate in pixels"
},
"fill": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Fill style as a CSS color string; omitted or empty for no fill"
},
"width": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Width in pixels"
},
"height": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Height in pixels"
},
"stroke": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Stroke style as a CSS color string; omitted or empty for no stroke"
},
"blockId": {
"type": "string",
"format": "at-uri",
"description": "The AT-URI of this block record"
},
"opacity": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Opacity from 0 to 1 (defaults to 1)"
},
"rotation": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Rotation in radians around the rect's center (defaults to 0)"
},
"strokeWidth": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Stroke width in pixels (defaults to 1)"
},
"cornerRadius": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Corner radius in pixels (defaults to 0)"
}
},
"description": "An axis-aligned rectangle, optionally rotated around its center"
}
A freehand stroke — a brush trace captured atomically. Sample points are written once as a single register value; individual points are not edited collaboratively. To redo the stroke, replace the points register
Properties
The AT-URI of this block record
Brush color as a CSS color string
Opacity from 0 to 1 (defaults to 1)
The stroke's samples as a single register whose value is an array of #strokePoint objects
Rotation in radians applied around (x, y) at render time (defaults to 0)
Brush width in pixels (base width if pressure modulates)
Origin X offset applied to the stroke at render time (defaults to 0)
Origin Y offset applied to the stroke at render time (defaults to 0)
View raw schema
{
"type": "object",
"required": [
"blockId"
],
"properties": {
"x": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Origin X offset applied to the stroke at render time (defaults to 0)"
},
"y": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Origin Y offset applied to the stroke at render time (defaults to 0)"
},
"color": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Brush color as a CSS color string"
},
"width": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Brush width in pixels (base width if pressure modulates)"
},
"points": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "The stroke's samples as a single register whose value is an array of #strokePoint objects"
},
"blockId": {
"type": "string",
"format": "at-uri",
"description": "The AT-URI of this block record"
},
"opacity": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Opacity from 0 to 1 (defaults to 1)"
},
"rotation": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Rotation in radians applied around (x, y) at render time (defaults to 0)"
}
},
"description": "A freehand stroke — a brush trace captured atomically. Sample points are written once as a single register value; individual points are not edited collaboratively. To redo the stroke, replace the points register"
}
A single sample within a #stroke. Used inline as an element of #stroke.points
Properties
Optional pen pressure, 0-255 (0 = lift, 255 = max)
minimum: 0maximum: 255
View raw schema
{
"type": "object",
"required": [
"x",
"y"
],
"properties": {
"x": {
"type": "integer",
"description": "X coordinate in pixels"
},
"y": {
"type": "integer",
"description": "Y coordinate in pixels"
},
"pressure": {
"type": "integer",
"maximum": 255,
"minimum": 0,
"description": "Optional pen pressure, 0-255 (0 = lift, 255 = max)"
}
},
"description": "A single sample within a #stroke. Used inline as an element of #stroke.points"
}
A text label rendered with canvas fillText/strokeText
Properties
Horizontal alignment relative to (x, y) — 'left', 'center', or 'right' (defaults to 'left')
The AT-URI of this block record
Fill style as a CSS color string; omitted or empty for no fill
Font family as a CSS font-family string
Opacity from 0 to 1 (defaults to 1)
Rotation in radians around (x, y) (defaults to 0)
Stroke style as a CSS color string; omitted or empty for no stroke
Stroke width in pixels (defaults to 0)
The text content as a text sequence (editable per-character)
Font weight as a CSS font-weight value
Anchor X coordinate in pixels
Anchor Y coordinate in pixels (text baseline)
View raw schema
{
"type": "object",
"required": [
"blockId"
],
"properties": {
"x": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Anchor X coordinate in pixels"
},
"y": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Anchor Y coordinate in pixels (text baseline)"
},
"fill": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Fill style as a CSS color string; omitted or empty for no fill"
},
"text": {
"ref": "page.corvus.core#sequence",
"type": "ref",
"description": "The text content as a text sequence (editable per-character)"
},
"align": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Horizontal alignment relative to (x, y) — 'left', 'center', or 'right' (defaults to 'left')"
},
"stroke": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Stroke style as a CSS color string; omitted or empty for no stroke"
},
"weight": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Font weight as a CSS font-weight value"
},
"blockId": {
"type": "string",
"format": "at-uri",
"description": "The AT-URI of this block record"
},
"opacity": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Opacity from 0 to 1 (defaults to 1)"
},
"fontSize": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Font size in pixels"
},
"rotation": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Rotation in radians around (x, y) (defaults to 0)"
},
"fontFamily": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Font family as a CSS font-family string"
},
"strokeWidth": {
"ref": "page.corvus.core#register",
"type": "ref",
"description": "Stroke width in pixels (defaults to 0)"
}
},
"description": "A text label rendered with canvas fillText/strokeText"
}