Module: ChunkyPNG

Defined in:
lib/chunky_png.rb,
lib/chunky_png/chunk.rb,
lib/chunky_png/color.rb,
lib/chunky_png/image.rb,
lib/chunky_png/point.rb,
lib/chunky_png/canvas.rb,
lib/chunky_png/vector.rb,
lib/chunky_png/palette.rb,
lib/chunky_png/rmagick.rb,
lib/chunky_png/version.rb,
lib/chunky_png/dimension.rb,
lib/chunky_png/datastream.rb,
lib/chunky_png/canvas/drawing.rb,
lib/chunky_png/canvas/masking.rb,
lib/chunky_png/canvas/operations.rb,
lib/chunky_png/canvas/resampling.rb,
lib/chunky_png/canvas/png_decoding.rb,
lib/chunky_png/canvas/png_encoding.rb,
lib/chunky_png/canvas/stream_exporting.rb,
lib/chunky_png/canvas/stream_importing.rb,
lib/chunky_png/canvas/adam7_interlacing.rb,
lib/chunky_png/canvas/data_url_exporting.rb,
lib/chunky_png/canvas/data_url_importing.rb

Overview

ChunkyPNG - the pure ruby library to access PNG files.

The ChunkyPNG module defines some constants that are used in the PNG specification, specifies some exception classes, and serves as a namespace for all the other modules and classes in this library.

Image:: class to represent PNG images, including metadata. Canvas:: class to represent the image's canvas. Color:: module to work with color values. Palette:: represents the palette of colors used on a Canvas. Datastream:: represents the internal structure of a PNG Image. Color:: represents one chunk of data within a Datastream. Point:: geometry helper class representing a 2-dimensional point. Dimension:: geometry helper class representing a dimension (i.e. width x height). Vector:: geometry helper class representing a series of points.

Author:

  • Willem van Bergen

Defined Under Namespace

Modules: Chunk, Color, RMagick Classes: CRCMismatch, Canvas, Datastream, Dimension, Exception, ExpectationFailed, Image, InvalidUTF8, NotSupported, OutOfBounds, Palette, Point, SignatureMismatch, UnitsUnknown, Vector

Constant Summary collapse

VERSION =

The current version of ChunkyPNG. Set it and commit the change this before running rake release.

"1.4.0"

Class Method Summary collapse

Class Method Details

.Color(r, g, b, a) ⇒ Integer .Color(r, g, b) ⇒ Integer .Color(hex_value, opacity = nil) ⇒ Integer .Color(color_name, opacity = nil) ⇒ Integer .Color(color_value, opacity = nil) ⇒ Integer

Factory method to return a color value, based on the arguments given.

Overloads:

  • .Color(r, g, b, a) ⇒ Integer

    Returns The rgba color value.

    Returns:

    • (Integer) —

      The rgba color value.

  • .Color(r, g, b) ⇒ Integer

    Returns The rgb color value.

    Returns:

    • (Integer) —

      The rgb color value.

  • .Color(hex_value, opacity = nil) ⇒ Integer

    Returns The hex color value, with the opacity applied if one was given.

    Returns:

    • (Integer) —

      The hex color value, with the opacity applied if one was given.

  • .Color(color_name, opacity = nil) ⇒ Integer

    Returns The hex color value, with the opacity applied if one was given.

    Returns:

    • (Integer) —

      The hex color value, with the opacity applied if one was given.

  • .Color(color_value, opacity = nil) ⇒ Integer

    Returns The color value, with the opacity applied if one was given.

    Parameters:

    • The (Integer, :to_i) —

      color value.

    Returns:

    • (Integer) —

      The color value, with the opacity applied if one was given.

Returns:

  • (Integer) —

    The determined color value as RGBA integer.

Raises:

  • (ArgumentError) —

    if the arguments weren't understood as a color.

See Also:



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# File 'lib/chunky_png/color.rb', line 33

def self.Color(*args) # rubocop:disable Naming/MethodName # API backwards compatibility
  case args.length
    when 1 then ChunkyPNG::Color.parse(args.first)
    when 2 then (ChunkyPNG::Color.parse(args.first) & 0xffffff00) | args[1].to_i
    when 3 then ChunkyPNG::Color.rgb(*args)
    when 4 then ChunkyPNG::Color.rgba(*args)
    else raise ArgumentError, "Don't know how to create a color from #{args.inspect}!"
  end
end

.Dimension(width, height) ⇒ ChunkyPNG::Dimension .Dimension(string) ⇒ ChunkyPNG::Dimension .Dimension(ary) ⇒ ChunkyPNG::Dimension .Dimension(hash) ⇒ ChunkyPNG::Dimension

Creates a Dimension instance using arguments that can be interpreted as width and height.

Overloads:

  • .Dimension(width, height) ⇒ ChunkyPNG::Dimension

    Returns The instantiated dimension.

    Parameters:

    • width (Integer) —

      The width-component of the dimension.

    • height (Integer) —

      The height-component of the dimension.

    Returns:

  • .Dimension(string) ⇒ ChunkyPNG::Dimension

    Returns The instantiated dimension.

    Parameters:

    • string (String) —

      A string from which a width and height value can be parsed, e.g. '10x20' or '[10, 20]'.

    Returns:

  • .Dimension(ary) ⇒ ChunkyPNG::Dimension

    Returns The instantiated dimension.

    Parameters:

    • ary (Array) —

      An array with the desired width as first element and the desired height as second element, e.g. [10, 20].

    Returns:

  • .Dimension(hash) ⇒ ChunkyPNG::Dimension

    Returns The instantiated dimension.

    Parameters:

    • hash (Hash) —

      An hash with a 'height' or :height key for the desired height and with a 'width' or :width key for the desired width.

    Returns:

Returns:

Raises:

  • (ArgumentError) —

    If the argument(s) given where not understood as a dimension.

See Also:



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# File 'lib/chunky_png/dimension.rb', line 31

def self.Dimension(*args)
  case args.length
  when 2 then ChunkyPNG::Dimension.new(*args)
  when 1 then build_dimension_from_object(args.first)
  else raise ArgumentError,
    "Don't know how to construct a dimension from #{args.inspect}"
  end
end

.Point(x, y) ⇒ ChunkyPNG::Point .Point(array) ⇒ ChunkyPNG::Point .Point(hash) ⇒ ChunkyPNG::Point .Point(string) ⇒ ChunkyPNG::Point

Factory method to create Point instances.

This method tries to be as flexible as possible with regards to the given input: besides explicit coordinates, this method also accepts arrays, hashes, strings, Dimension instances and anything that responds to :x and :y.

Overloads:

  • .Point(x, y) ⇒ ChunkyPNG::Point

    Returns The instantiated point.

    Parameters:

    • x (Integer, :to_i) —

      The x-coordinate

    • y (Integer, :to_i) —

      The y-coordinate

    Returns:

  • .Point(array) ⇒ ChunkyPNG::Point

    Returns The instantiated point.

    Parameters:

    • array (Array<Integer>) —

      A two element array which represent the x- and y-coordinate.

    Returns:

  • .Point(hash) ⇒ ChunkyPNG::Point

    Returns The instantiated point.

    Parameters:

    • array (Hash) —

      A hash with the :x or 'x' and :y or 'y' keys set, which will be used as coordinates.

    Returns:

  • .Point(string) ⇒ ChunkyPNG::Point

    Returns The instantiated point.

    Parameters:

    • string (String) —

      A string that contains the coordinates, e.g. '0, 4', '(0 4)', [0,4}', etc.

    Returns:

Returns:

Raises:

  • (ArgumentError) —

    if the arguments weren't understood.

See Also:



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# File 'lib/chunky_png/point.rb', line 32

def self.Point(*args)
  case args.length
  when 2 then ChunkyPNG::Point.new(*args)
  when 1 then build_point_from_object(args.first)
  else raise ArgumentError,
    "Don't know how to construct a point from #{args.inspect}!"
  end
end

.Vector(x0, y0, x1, y1, x2, y2, ...) ⇒ ChunkyPNG::Vector .Vector(string) ⇒ ChunkyPNG::Vector .Vector(pointlike, pointlike, pointlike, ...) ⇒ ChunkyPNG::Vector

Factory method for Vector instances.

Overloads:

  • .Vector(x0, y0, x1, y1, x2, y2, ...) ⇒ ChunkyPNG::Vector

    Creates a vector by parsing two subsequent values in the argument list as x- and y-coordinate of a point.

    Returns:

  • .Vector(string) ⇒ ChunkyPNG::Vector

    Creates a vector by parsing coordinates from the input string.

    Returns:

  • .Vector(pointlike, pointlike, pointlike, ...) ⇒ ChunkyPNG::Vector

    Creates a vector by converting every argument to a point using Point.

    Returns:

Returns:

Raises:

  • (ArgumentError) —

    If the given arguments could not be understood as a vector.

See Also:



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# File 'lib/chunky_png/vector.rb', line 20

def self.Vector(*args)
  return args.first if args.length == 1 && args.first.is_a?(ChunkyPNG::Vector)

  if args.length == 1 && args.first.respond_to?(:scan)
    ChunkyPNG::Vector.new(ChunkyPNG::Vector.multiple_from_string(args.first)) # e.g. ['1,1 2,2 3,3']
  else
    ChunkyPNG::Vector.new(ChunkyPNG::Vector.multiple_from_array(args)) # e.g. [[1,1], [2,2], [3,3]] or [1,1,2,2,3,3]
  end
end