View Source Image.Shape (image v0.15.0)
Functions to render a shape as an image. The supported shapes match those defined in Scalable Vector Graphics including:
- Polygon
- Circle
- Ellipse
- Line
Link to this section Summary
Types
A path is a list of points representing a path, open polygon or closed polygon.
A point is a list of two integers
representing the x and y coordinates
Functions
Creates an image of a polygon as a single band image on a transparent background.
Creates an image of a polygon as a single band image on a transparent background.
Returns an image of an n-pointed star that can be composed over other images.
Returns an image of an n-pointed star that can be composed over other images.
Link to this section Types
A path is a list of points representing a path, open polygon or closed polygon.
@type point() :: [integer()]
A point is a list of two integers
representing the x and y coordinates
Link to this section Functions
@spec polygon(points :: path(), options :: Keyword.t()) :: {:ok, Vix.Vips.Image.t()} | {:error, Image.error_message()}
@spec polygon(sides :: pos_integer(), options :: Keyword.t()) :: {:ok, Vix.Vips.Image.t()} | {:error, Image.error_message()}
Creates an image of a polygon as a single band image on a transparent background.
arguments
Arguments
pointsdefines the points of the polygon. The origin is the top left of the image with a positivexvalue moving from right to left and a positiveyvalue moving from top to bottom. The points can be an SVG point string or a "list of lists" of the form[[x1, y1], [x2, y2], ...]wherex1andy1are integers.pointscan also be a positive integer >= 3 which indicates that annsided polygon will be generated. In this case the options:rotationand:radiusare also applicable.optionsis aKeyword.t/0list of options.
options
Options
:widthis the width of the canvas onto which the polygon is drawn. The default is500pixels.:heightis the width of the canvas onto which the polygon is drawn. The default is500pixels.:fill_coloris the color used to fill in the polygon. The default is:none.:stroke_coloris the color used for the outline of the polygon. The default is:black:opacityis the opacity as a float between0.0and1.0where0.0is completely transparent and1.0is completely opaque. The default is0.7.:rotationis the number of degrees to rotate the axis of a generated n-sided polygon. This option is only valid ifpointsis an integer >= 3. The default is180.:radiusindicates the radius in pixels of a generated n-sided polygon. The default is100.
notes
Notes
The polygon points are scaled to fit the canvas size defined by
:widthand:heightThis means that the resulting image will fill the canvas. This is useful for composing images. Define the canvas to be the size intended to be composed into a base image and the polygon will be scaled to fit.Colors may be any valid CSS color name or a six hexadecimal digit string prefixed with
#. For example#FF00FFfor the color "Fuchsia".
returns
Returns
{:ok, image}or{:error, reason}
examples
Examples
@spec polygon!(points :: path(), options :: Keyword.t()) :: Vix.Vips.Image.t() | no_return()
Creates an image of a polygon as a single band image on a transparent background.
arguments
Arguments
pointsdefines the points of the polygon. The origin is the top left of the image with a positivexvalue moving from right to left and a positiveyvalue moving from top to bottom. The points can be an SVG point string or a "list of lists" of the form[[x1, y1], [x2, y2], ...]wherex1andy1are integers.optionsis aKeyword.t/0list of options.
options
Options
:widthis the width of the canvas onto which the polygon is drawn. The default is500pixels.:heightis the width of the canvas onto which the polygon is drawn. The default is500pixels.:fill_coloris the color used to fill in the polygon. The default is:none.:stroke_coloris the color used for the outline of the polygon. The default is:black:opacityis the opacity as a float between0.0and1.0where0.0is completely transparent and1.0is completely opaque. The default is0.7.
notes
Notes
The polygon points are scaled to fit the canvas size defined by
:widthand:heightThis means that the resulting image will fill the canvas. This is useful for composing images. Define the canvas to be the size intended to be composed into a base image and the polygon will be scaled to fit.Colors may be any valid CSS color name or a six hexadecimal digit string prefixed with
#. For example#FF00FFfor the color "Fuchsia".
returns
Returns
imageorraises an exception
examples
Examples
@spec star(points :: pos_integer(), options :: Keyword.t()) :: {:ok, Vix.Vips.Image.t()} | {:error, Image.error_message()}
Returns an image of an n-pointed star that can be composed over other images.
arguments
Arguments
pointsis an integer number of points on the star.pointsmust be >= 3. The default is5.optionsis aKeyword.t/0list of options.
options
Options
:inner_radiusis the size of the inner radius. The default is60.:outer_radiusis the size of the outer radius. The default is150.:rotationis the angle in degrees of rotation applied to the points. The default is0.Any remaining options are passed to
Image.Shape.polygon/2.
returns
Returns
{:ok, image}or{:error, reason}
examples
Examples
#=> {:ok, star} = Image.Shape.star
#=> {:ok, star} = Image.Shape.star 5, rotation: 90, fill_color: :red, stroke_color: :green@spec star!(points :: pos_integer(), options :: Keyword.t()) :: Vix.Vips.Image.t() | no_return()
Returns an image of an n-pointed star that can be composed over other images.
arguments
Arguments
pointsis an integer number of points on the star.pointsmust be >= 3. The default is5.optionsis aKeyword.t/0list of options.
options
Options
:inner_radiusis the size of the inner radius. The default is60.:outer_radiusis the size of the outer radius. The default is60.:rotationis the angle in degrees of rotation applied to the points. The default is0.Any remaining options are passed to
Image.Shape.polygon/2.
returns
Returns
imageorraises an exception
examples
Examples
#=> star = Image.Shape.star!
#=> star = Image.Shape.star! 5, rotation: 90, fill_color: :red, stroke_color: :green