ExPng v1.0.0

ExPng.Image.Drawing (ExPng v1.0.0)

Utility module to hold functions related to drawing on images.

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Types

coordinate_pair()

Functions

at(image, coordinates)

Returns the pixel at the given {x, y} coordinates in the image.

clear(image, coordinates)

Clears the pixel at the given {x, y} coordinates in the image, coloring it opaque white.

draw(image, coordinates, color \\ Color.black())

Colors the pixel at the given {x, y} coordinates in the image the provided color.

erase(image)

Erases all content in the image, setting every pixel to opaque white

line(image, coordinates0, coordinates1, color \\ Color.black())

Draws a line between the given coordinates in the image.

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coordinate_pair()

Specs

coordinate_pair() :: {pos_integer(), pos_integer()}

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at(image, coordinates)

Specs

at(ExPng.Image.t(), coordinate_pair()) :: ExPng.Color.t()

Returns the pixel at the given {x, y} coordinates in the image.

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clear(image, coordinates)

Specs

clear(ExPng.Image.t(), coordinate_pair()) :: ExPng.Image.t()

Clears the pixel at the given {x, y} coordinates in the image, coloring it opaque white.

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draw(image, coordinates, color \\ Color.black())

Specs

draw(ExPng.Image.t(), coordinate_pair(), ExPng.maybe(ExPng.Color.t())) ::
  ExPng.Image.t()

Colors the pixel at the given {x, y} coordinates in the image the provided color.

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erase(image)

Specs

erase(ExPng.Image.t()) :: ExPng.Image.t()

Erases all content in the image, setting every pixel to opaque white

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line(image, coordinates0, coordinates1, color \\ Color.black())

Specs

line(
  ExPng.Image.t(),
  coordinate_pair(),
  coordinate_pair(),
  ExPng.maybe(ExPng.Color.t())
) :: ExPng.Image.t()

Draws a line between the given coordinates in the image.

Shortcut functions are provided for horizontal lines, vertical lines, and lines with a slope of 1 or -1. For other angles, Xiaolin Wu's algorithm for drawing anti-aliased lines is used.