marks
specification includes the following properties:x
and y
scales to the x
and y
database table columns to scale the data to the visualization area width and height. For example:type
property that specifies the geometric primitive to use to render the data.x
and y
coordinate values using either constants, or domain and range values of a data
reference. If the from
property is not specified, the x
and y
properties
fields must be constants.points
geometric primitive with tweets
data items.data
format
property as lines
causes the rendering engine to assume a lines
database table layout and to extract line-related columns from the table.x
and y
coordinate values using either constants, or domain and range values of a data
reference. If the from
property is not specified, the x
and y
properties
fields must be constants.polys
type renders data as a polygon.
When the data
format property is polys
, the rendering engine assumes a polys
database table layout and extracts the poly-related columns from the table. A polys
database table layout implies that the first data column is the vertex x- and y-positions. The vertices are interleaved x and y values, such that vertex[0] = vert0.x
, vertex[1] = vert0.y
, vertex[2] = vert1.x
, and vertex[3] = vert1.y
, for example. The next three positions of a polys
database table are the triangulated indices, and line loop and drawing information for unpacking multiple, associated polygons that can be packed as a single data item.symbol
mark types, strokes are not visible beneath other marks, regardless of opacity settings.x
and y
coordinate values using either constants or domain and range values of a data
reference. If the from
property is not specified, the x
and y
properties
fields must be specified using constant values.symbol
Examplesfrom
field specifies the input database table to use.tweets
database table for marks input data.from
is not specified, the data source is implicitly a single point with the value defined in the points
properties.properties
property specifies type-dependent visual encoding that define the position and appearance of mark instances. The property value is specified using one of the Value Reference options.polys
, which uses multiple data elements to represent a line or area shape.properties
and lists the types for which the property is valid.angle
x
and y
: Lower-left corner.x
and yc
: Left center.xc
and y
: Bottom center.xc
and yc
: Center.angleUnit
angle
. Either degrees
(default) or radians
.fillColor
fillOpacity
0
) to opaque (1
). If used with opacity
, the values are multiplied together to determine final opacity.height
lineJoin
bevel
- Extension of a line endmiter
- Clipped extension of a line endround
- Semi-circle at a line endmiterLimit
10.0
opacity
0
) to opaque (1
). If used with fillOpacity
(points
, polys
, symbol
) or strokeOpacity
(lines), the values are multiplied together to determine final opacity.shape
circle
cross
diamond
hexagon-horiz
hexagon-vert
square
triangle-down
triangle-left
triangle-right
triangle-up
wedge
size
stroke
strokeColor
white
strokeOpacity
0
) to opaque (1
). If used with opacity
, the values are multiplied together to determine final opacity.strokeWidth
width
x
polys
, or a scale/data reference or a number for points
, lines
, or symbol
. See Value Reference.y
polys
, or a scale/data reference or a number for points
, lines
, or symbol
. See Value Reference.properties
values. The value can be a constant or data object reference:value
field
is specified, value
is ignored.field
from
property determines the source data table and the field
name must be a column defined in the data
property.scale
fillColor
and size
.x
marks property, apply the x
scale transform to the implicit x-coordinate data column.field
data: sql
field.colorSpace
r
, g
, and b
property names.h
, s
, and l
property names.l
, a
, and b
property names.h
, c
, and l
property names.rgb
color space for the color
field:transform
object specifies any Vega projections to be applied to the mark. Each transform is specified as a key:value pair in the transform
object:my_mercator_projection
defined in the top-level Vega projections
property.projection
.