Class: Fleximage::Operator::Crop

Inherits:
Base
  • Object
show all
Defined in:
lib/fleximage/operator/crop.rb

Overview

Crops the image without doing any resizing first. The operation crops from the :from coordinate, and returns an image of size :size down and right from there.

image.crop(options = {})

Use the following keys in the options hash:

  • gravity: Select gravity for the crop. Default is :top_left (Magick::NorthWestGravity) Choose from GRAVITITES constant defined in base.rb.

  • from: coorinates for the upper left corner of resulting image.

  • size: The size of the resulting image, going down and to the right of the :from coordinate.

size and from options are *required*.

Example:

@photo.operate do |image|
  image.crop(
    :from => '100x50',
    :size => '500x350'
  )
end

or

@photo.operate do |image|
  image.crop(
    :gravity => :center,
    :from    => '100x50',
    :size    => '500x350'
  )
end

Instance Method Summary collapse

Methods inherited from Base

#color, color, #execute, #initialize, #scale, #scale_and_crop, size_to_xy, #size_to_xy, #stretch, #symbol_to_blending_mode, #symbol_to_gravity

Constructor Details

This class inherits a constructor from Fleximage::Operator::Base

Instance Method Details

#operate(options = {}) ⇒ Object 



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# File 'lib/fleximage/operator/crop.rb', line 37

def operate(options = {})
  options = options.symbolize_keys
  options.reverse_merge!(:gravity => :top_left)

  # required integer keys
  [:from, :size].each do |key|
    raise ArgumentError, ":#{key} must be included in crop options" unless options[key]
    options[key] = size_to_xy(options[key])
  end

  # width and height must not be zero
  options[:size].each do |dimension|
    raise ArgumentError, ":size must not be zero for X or Y" if dimension.zero?
  end

  # crop
  @image.crop!(symbol_to_gravity(options[:gravity]), options[:from][0], options[:from][1], options[:size][0], options[:size][1], true)
end