Module: TableTennis::Util::Scale

Includes:
MemoWise
Defined in:
lib/table_tennis/util/scale.rb

Overview

Helpers for color scales (adding background colors to a column based on the value of the float in the cell). Like conditional formattiong with a color range in google sheets.

Constant Summary collapse

SCALES = 
{
  # white => color
  g: [WHITE, GREEN],
  y: [WHITE, YELLOW],
  r: [WHITE, RED],
  b: [WHITE, BLUE],

  # green/yellow/red => white
  gw: [GREEN, WHITE],
  yw: [YELLOW, WHITE],
  rw: [RED, WHITE],
  bw: [BLUE, WHITE],

  # red <=> green
  rg: [RED, WHITE, GREEN],
  gr: [GREEN, WHITE, RED],
  gyr: [GREEN, YELLOW, RED],
}

Class Method Summary collapse

Class Method Details

.color_stops(name) ⇒ Object 



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# File 'lib/table_tennis/util/scale.rb', line 47

def color_stops(name)
  SCALES[name].map { Colors.to_rgb(_1) }.transpose
end

.interpolate(name, t) ⇒ Object 



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# File 'lib/table_tennis/util/scale.rb', line 32

def interpolate(name, t)
  t = t.clamp(0, 1).to_f
  stops = color_stops(name)
  rgb = if stops.first.length == 2
    stops.map { lerp(t, _1, _2) }
  elsif t < 0.5
    t *= 2
    stops.map { lerp(t, _1, _2) }
  else
    t = (t - 0.5) * 2
    stops.map { lerp(t, _2, _3) }
  end
  Colors.to_hex(rgb)
end

.lerp(t, v0, v1) ⇒ Object 



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# File 'lib/table_tennis/util/scale.rb', line 52

def lerp(t, v0, v1) = t * (v1 - v0) + v0