feature(ImageViewer): Add FilterControls component to ImageViewer

packages/core/src/components/ImageViewer/FilterControls.tsx

@@ -0,0 +1,127 @@
+import React, { useCallback, useState } from 'react';
+import IconTune from '@airbnb/lunar-icons/lib/interface/IconTune';
+import ButtonGroup from '../ButtonGroup';
+import Card, { Content } from '../Card';
+import Dropdown from '../Dropdown';
+import IconButton from '../IconButton';
+import Range from '../Range';
+import Text from '../Text';
+import T from '../Translate';
+import useStyles, { StyleSheet } from '../../hooks/useStyles';
+
+export type FilterControlsProps = {
+  /** The current brightness. 1 by default. Valid range: 0 -> ∞. */
+  brightness?: number;
+  /** Callback when brightness changes. */
+  onBrightnessChange: (brightness: number) => void;
+  /** The current contrast. 1 by default. Valid range: 0 -> ∞. */
+  contrast?: number;
+  /** Callback when contrast changes. */
+  onContrastChange: (contrast: number) => void;
+  /** Size of the icons. */
+  iconSize?: number | string;
+  /** Place dropdown menu above. */
+  dropdownAbove?: boolean;
+};
+
+const styleSheet: StyleSheet = () => ({
+  controls: {
+    position: 'relative',
+  },
+  filterLabel: {
+    width: 100,
+  },
+  filterRow: {
+    alignItems: 'baseline',
+    display: 'flex',
+  },
+});
+
+/** Filter controls that can be used with an image viewer component */
+export default function FilterControls(props: FilterControlsProps) {
+  const [styles, cx] = useStyles(styleSheet);
+  const [visible, setVisible] = useState(false);
+
+  const {
+    onBrightnessChange,
+    brightness = 1,
+    onContrastChange,
+    contrast = 1,
+    iconSize = '2em',
+    dropdownAbove,
+  } = props;
+
+  const handleBrightnessChange = useCallback(
+    (v) => {
+      onBrightnessChange(10 ** v);
+    },
+    [onBrightnessChange],
+  );
+
+  const handleContrastChange = useCallback(
+    (v) => {
+      onContrastChange(10 ** v);
+    },
+    [onContrastChange],
+  );
+
+  const toggleContrastPicker = useCallback(() => setVisible(!visible), [visible]);
+
+  return (
+    <ButtonGroup>
+      <div className={cx(styles.controls)}>
+        <IconButton onClick={toggleContrastPicker}>
+          <IconTune
+            accessibilityLabel={T.phrase('lunar.image.adjustContrast', 'Adjust contrast')}
+            size={iconSize}
+          />
+        </IconButton>
+
+        {visible && (
+          <Dropdown
+            visible={visible}
+            bottom={dropdownAbove ? '100%' : undefined}
+            left={0}
+            zIndex={5}
+            onClickOutside={toggleContrastPicker}
+          >
+            <Card>
+              <Content>
+                <div className={cx(styles.filterRow)}>
+                  <div className={cx(styles.filterLabel)}>
+                    <Text>{T.phrase('lunar.image.brightness', 'Brightness')}</Text>
+                  </div>
+                  <Range
+                    hideLabel
+                    label="brightness"
+                    width={200}
+                    min={-0.5}
+                    max={0.5}
+                    step={0.05}
+                    value={Math.log10(brightness)}
+                    onChange={handleBrightnessChange}
+                  />
+                </div>
+                <div className={cx(styles.filterRow)}>
+                  <div className={cx(styles.filterLabel)}>
+                    <Text>{T.phrase('lunar.image.contrast', 'Contrast')}</Text>
+                  </div>
+                  <Range
+                    hideLabel
+                    label="contrast"
+                    width={200}
+                    min={-0.5}
+                    max={0.5}
+                    step={0.05}
+                    value={Math.log10(contrast)}
+                    onChange={handleContrastChange}
+                  />
+                </div>
+              </Content>
+            </Card>
+          </Dropdown>
+        )}
+      </div>
+    </ButtonGroup>
+  );
+}

packages/core/src/components/ImageViewer/index.tsx

@@ -1,5 +1,6 @@
 import React, { useState, useEffect } from 'react';
 import useStyles, { StyleSheet } from '../../hooks/useStyles';
+import FilterControls from './FilterControls';
 import ZoomControls from './ZoomControls';
 import RotateControls from './RotateControls';
 import ResponsiveImage from '../ResponsiveImage';
@@ -18,6 +19,10 @@ export type ImageViewerProps = {
   src: string;
   /** The current scale / zoom level. 1 by default. */
   scale?: number;
+  /** The current brightness. 1 by default. */
+  brightness?: number;
+  /** The current contrast. 1 by default. */
+  contrast?: number;
   /** Render width. Unconstrained (css value 'none') by default. */
   width?: number | string;
   /** Custom style sheet. */
@@ -36,6 +41,8 @@ export default function ImageViewer({
   height = 'none',
   rotation = 0,
   scale = 1,
+  brightness = 1,
+  contrast = 1,
   src,
   width,
   styleSheet,
@@ -101,6 +108,7 @@ export default function ImageViewer({
   const translateX = (y * sinRotation + x * cosRotation) / scale;
   const translateY = (y * cosRotation - x * sinRotation) / scale;
   const transform = `scale(${scale}) rotate(${rotation}deg) translateY(${translateY}px) translateX(${translateX}px)`;
+  const filter = `brightness(${brightness}) contrast(${contrast})`;
 
   return (
     <div
@@ -110,7 +118,7 @@ export default function ImageViewer({
       onMouseDown={handleMouseDown}
       onMouseUp={handleMouseUp}
     >
-      <div className={cx(styles.image)} style={{ transform }}>
+      <div className={cx(styles.image)} style={{ transform, filter }}>
         <ResponsiveImage
           contain
           noShadow
@@ -125,4 +133,4 @@ export default function ImageViewer({
   );
 }
 
-export { ZoomControls, RotateControls };
+export { FilterControls, ZoomControls, RotateControls };

packages/core/src/components/ImageViewer/story.tsx

@@ -1,15 +1,24 @@
 import React, { useState } from 'react';
 import space from ':storybook/images/space.jpg';
-import ImageViewer, { ZoomControls, RotateControls } from '.';
-import Row from '../Row';
+import ImageViewer, { FilterControls, ZoomControls, RotateControls } from '.';
+import useStyles, { StyleSheet } from '../../hooks/useStyles';
 
 type ImageViewerDemoProps = {
   width?: string;
   height?: string;
   controlsBottom?: boolean;
 };
 
+const styleSheet: StyleSheet = () => ({
+  controls: {
+    display: 'flex',
+  },
+});
+
 function ImageViewerDemo({ width, height, controlsBottom }: ImageViewerDemoProps) {
+  const [styles, cx] = useStyles(styleSheet);
+  const [brightness, setBrightness] = useState(1);
+  const [contrast, setContrast] = useState(1);
   const [scale, setScale] = useState(1);
   const [rotation, setRotation] = useState(0);
 
@@ -20,31 +29,42 @@ function ImageViewerDemo({ width, height, controlsBottom }: ImageViewerDemoProps
         scale={scale}
         src={space}
         rotation={rotation}
+        brightness={brightness}
+        contrast={contrast}
         height={height}
         width={width}
       />
-      <Row
-        before={
-          <RotateControls rotation={rotation} onRotation={(value: number) => setRotation(value)} />
-        }
-      >
+      <div className={cx(styles.controls)}>
+        <FilterControls
+          dropdownAbove
+          brightness={brightness}
+          contrast={contrast}
+          onBrightnessChange={(value: number) => setBrightness(value)}
+          onContrastChange={(value: number) => setContrast(value)}
+        />
+        <RotateControls rotation={rotation} onRotation={(value: number) => setRotation(value)} />
         <ZoomControls dropdownAbove scale={scale} onScale={(value: number) => setScale(value)} />
-      </Row>
+      </div>
     </>
   ) : (
     <>
-      <Row
-        before={
-          <RotateControls rotation={rotation} onRotation={(value: number) => setRotation(value)} />
-        }
-      >
+      <div className={cx(styles.controls)}>
+        <FilterControls
+          brightness={brightness}
+          contrast={contrast}
+          onBrightnessChange={(value: number) => setBrightness(value)}
+          onContrastChange={(value: number) => setContrast(value)}
+        />
+        <RotateControls rotation={rotation} onRotation={(value: number) => setRotation(value)} />
         <ZoomControls scale={scale} onScale={(value: number) => setScale(value)} />
-      </Row>
+      </div>
       <ImageViewer
         alt="Testing"
         scale={scale}
         src={space}
         rotation={rotation}
+        brightness={brightness}
+        contrast={contrast}
         height={height}
         width={width}
       />
@@ -55,7 +75,7 @@ function ImageViewerDemo({ width, height, controlsBottom }: ImageViewerDemoProps
 export default {
   title: 'Core/ImageViewer',
   parameters: {
-    inspectComponents: [ImageViewer, ZoomControls, RotateControls],
+    inspectComponents: [ImageViewer, FilterControls, ZoomControls, RotateControls],
   },
 };