Contents

/**
 * Copyright 2016 Google Inc. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

@import "./constants";

/* All variables are local, so disable pattern checking. */
/* stylelint-disable scss/dollar-variable-pattern */

/**
 * Calculate the luminance for a color.
 * See https://www.w3.org/TR/WCAG20-TECHS/G17.html#G17-tests
 */
@function mdc-theme-luminance($color) {
  $red: nth($mdc-theme-linear-channel-values, red($color) + 1);
  $green: nth($mdc-theme-linear-channel-values, green($color) + 1);
  $blue: nth($mdc-theme-linear-channel-values, blue($color) + 1);

  @return .2126 * $red + .7152 * $green + .0722 * $blue;
}

/**
 * Calculate the contrast ratio between two colors.
 * See https://www.w3.org/TR/WCAG20-TECHS/G17.html#G17-tests
 */
@function mdc-theme-contrast($back, $front) {
  $backLum: mdc-theme-luminance($back) + .05;
  $foreLum: mdc-theme-luminance($front) + .05;

  @return max($backLum, $foreLum) / min($backLum, $foreLum);
}

/**
 * Determine whether to use dark or light text on top of given color.
 * Returns "dark" for dark text and "light" for light text.
 */
@function mdc-theme-light-or-dark($color) {
  $minimumContrast: 3.1;

  $lightContrast: mdc-theme-contrast($color, white);
  $darkContrast: mdc-theme-contrast($color, rgba(black, .87));

  @if ($lightContrast < $minimumContrast) and ($darkContrast > $lightContrast) {
    @return "dark";
  }

  @else {
    @return "light";
  }
}

/* stylelint-enable scss/dollar-variable-pattern */

Version data entries

2 entries across 2 versions & 1 rubygems

Version	Path
material_components_web-sass-0.2.0	vendor/assets/stylesheets/@material/theme/_functions.scss
material_components_web-sass-0.1.1	vendor/assets/stylesheets/@material/theme/_functions.scss