Class: ZPNG::BMP::BmpPaletteChunk

Inherits:
Chunk::PLTE show all
Defined in:
lib/zpng/bmp/reader.rb

Constant Summary

Constants inherited from Chunk

Chunk::KNOWN_TYPES, Chunk::VALID_SIZE_RANGE

Instance Attribute Summary

Attributes inherited from Chunk::PLTE

#max_colors

Attributes inherited from Chunk

#crc, #data, #idx, #offset, #size, #type

Instance Method Summary collapse

Methods inherited from Chunk::PLTE

#add, #each, #each_with_index, #find_or_add, #index, #to_a

Methods inherited from Chunk

#check, #crc_ok?, #export, #export_data, #fix_crc!, from_stream, #valid?

Methods included from DeepCopyable

#deep_copy

Constructor Details

#initialize(data) ⇒ BmpPaletteChunk

Returns a new instance of BmpPaletteChunk.



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# File 'lib/zpng/bmp/reader.rb', line 104

def initialize data
  super(
    :crc  => :no_crc,
    :data => data,
    :type => 'PALETTE'
  )
end

Instance Method Details

#[](idx) ⇒ Object 



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# File 'lib/zpng/bmp/reader.rb', line 112

def [] idx
  rgbx = @data[idx*4,4]
  rgbx && Color.new(*rgbx.unpack('C4'))
end

#[]=(idx, color) ⇒ Object 



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# File 'lib/zpng/bmp/reader.rb', line 117

def []= idx, color
  @data ||= ''
  @data[idx*4,4] = [color.r, color.g, color.b, color.a].pack('C4')
end

#inspect(*args) ⇒ Object 



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# File 'lib/zpng/bmp/reader.rb', line 126

def inspect *args
  "<%s ncolors=%d>" % ["PALETTE", size/4]
end

#ncolors ⇒ Object 



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# File 'lib/zpng/bmp/reader.rb', line 122

def ncolors
  @data.to_s.size/4
end