static int blendRGBInts(double bish, int a, int b) {
  ret blendRGBInts(a, b, bish);
}

static int blendRGBInts(int a, int b, double bish) {
  bish = normalizeTo0to1(bish);
  ret rgbInt(
    blend(rgbRed(a), rgbRed(b), bish),
    blend(rgbGreen(a), rgbGreen(b), bish),
    blend(rgbBlue(a), rgbBlue(b), bish));
}

Began life as a copy of #1007920