Method: PSD::Renderer::Blender#compose!

Defined in:
lib/psd/renderer/blender.rb

#compose! ⇒ Object

Composes the foreground Canvas onto the background Canvas using the blending mode specified by the foreground.



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# File 'lib/psd/renderer/blender.rb', line 18

def compose!
  PSD.logger.debug "#{fg.node.debug_name} -> #{bg.node.debug_name}: #{fg.node.blending_mode} blending"
  PSD.logger.debug "fg: (#{fg.left}, #{fg.top}) #{fg.width}x#{fg.height}; bg: (#{bg.left}, #{bg.top}) #{bg.width}x#{bg.height}"

  offset_x = fg.left - bg.left
  offset_y = fg.top - bg.top

  fg.height.times do |y|
    fg.width.times do |x|
      base_x = x + offset_x
      base_y = y + offset_y

      next if base_x < 0 || base_y < 0 || base_x >= bg.width || base_y >= bg.height

      color = Compose.send(
        fg.node.blending_mode,
        fg.get_pixel(x, y),
        bg.get_pixel(base_x, base_y),
        calculated_opacity
      )

      bg.set_pixel base_x, base_y, color
    end
  end
end