Module: Idml::Render::ColorHelper

Defined in:
lib/idml/render/color_helper.rb

Overview

Converts IDML color hashes to pdfrb Canvas color arrays and applies tint scaling. Centralizes the mapping so all renderers use a consistent format.

Class Method Summary collapse

Class Method Details

.apply_tint(color, tint) ⇒ Object

Scales a color's components by tint (1.0 = full strength, 0.5 = halved). Tint is the IDML mechanism for lightening a color without defining a new one. Returns the original color unchanged when tint is nil or >= 1.0. Single canonical implementation — CharacterStyle, ParagraphRules, and any future caller should all delegate here.



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# File 'lib/idml/render/color_helper.rb', line 29

def apply_tint(color, tint)
  return color unless color
  return color unless tint
  return color if tint >= 1.0

  case color[:model]
  when :rgb
    { model: :rgb, r: color[:r] * tint, g: color[:g] * tint,
      b: color[:b] * tint }
  when :cmyk
    { model: :cmyk, c: color[:c] * tint, m: color[:m] * tint,
      y: color[:y] * tint, k: color[:k] * tint }
  else
    color
  end
end

.to_canvas(color) ⇒ Object

Accepts a ColorResolver hash ({ model: :rgb, r:, g:, b: } or { model: :cmyk, c:, m:, y:, k: }) and returns the pdfrb Canvas array format ([:rgb, r, g, b] or [:cmyk, c, m, y, k]).



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# File 'lib/idml/render/color_helper.rb', line 14

def to_canvas(color)
  return nil unless color

  case color[:model]
  when :rgb then [:rgb, color[:r], color[:g], color[:b]]
  when :cmyk then [:cmyk, color[:c], color[:m], color[:y], color[:k]]
  end
end