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# File 'lib/psd/renderer/compose.rb', line 107
def screen(fg, bg, opacity)
return apply_opacity(fg, opacity) if fully_transparent?(bg)
return bg if fully_transparent?(fg)
mix_alpha, dst_alpha = calculate_alphas(fg, bg, opacity)
new_r = blend_channel(r(bg), 255 - ((255 - r(bg)) * (255 - r(fg)) >> 8), mix_alpha)
new_g = blend_channel(g(bg), 255 - ((255 - g(bg)) * (255 - g(fg)) >> 8), mix_alpha)
new_b = blend_channel(b(bg), 255 - ((255 - b(bg)) * (255 - b(fg)) >> 8), mix_alpha)
rgba(new_r, new_g, new_b, dst_alpha)
end
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