feat(ssr): add emphasis style in ssr css apache/echarts#18334

src/Element.ts

@@ -1017,6 +1017,22 @@ class Element<Props extends ElementProps = ElementProps> {
         }
     }
 
+    /**
+     * Return if el.silent or any ancestor element has silent true.
+     */
+    isSilent() {
+        let isSilent = this.silent;
+        let ancestor = this.parent;
+        while (!isSilent && ancestor) {
+            if (ancestor.silent) {
+                isSilent = true;
+                break;
+            }
+            ancestor = ancestor.parent;
+        }
+        return isSilent;
+    }
+
     /**
      * Update animation targets when reference is changed.
      */

src/svg/Painter.ts

@@ -124,10 +124,11 @@ class SVGPainter implements PainterBase {
     }
 
     renderToVNode(opts?: {
-        animation?: boolean
-        willUpdate?: boolean
+        animation?: boolean,
+        willUpdate?: boolean,
         compress?: boolean,
-        useViewBox?: boolean
+        useViewBox?: boolean,
+        emphasis?: boolean
     }) {
 
         opts = opts || {};
@@ -140,6 +141,7 @@ class SVGPainter implements PainterBase {
         scope.animation = opts.animation;
         scope.willUpdate = opts.willUpdate;
         scope.compress = opts.compress;
+        scope.emphasis = opts.emphasis;
 
         const children: SVGVNode[] = [];
 
@@ -173,7 +175,12 @@ class SVGPainter implements PainterBase {
          * If add css animation.
          * @default true
          */
-        cssAnimation?: boolean
+        cssAnimation?: boolean,
+        /**
+         * If add css emphasis.
+         * @default true
+         */
+        cssEmphasis?: boolean,
         /**
          * If use viewBox
          * @default true
@@ -183,6 +190,7 @@ class SVGPainter implements PainterBase {
         opts = opts || {};
         return vNodeToString(this.renderToVNode({
             animation: retrieve2(opts.cssAnimation, true),
+            emphasis: retrieve2(opts.cssEmphasis, true),
             willUpdate: false,
             compress: true,
             useViewBox: retrieve2(opts.useViewBox, true)

src/svg/core.ts

@@ -8,6 +8,7 @@ export const SVGNS = 'http://www.w3.org/2000/svg';
 export const XLINKNS = 'http://www.w3.org/1999/xlink';
 export const XMLNS = 'http://www.w3.org/2000/xmlns/';
 export const XML_NAMESPACE = 'http://www.w3.org/XML/1998/namespace';
+export const META_DATA_PREFIX = 'ecmeta_';
 
 export function createElement(name: string) {
     return document.createElementNS(SVGNS, name);
@@ -128,8 +129,11 @@ export interface BrushScope {
 
     cssNodes: Record<string, CSSSelectorVNode>
     cssAnims: Record<string, Record<string, Record<string, string>>>
+    /**
+     * Cache for css style string, mapping from style string to class name.
+     */
+    cssStyleCache: Record<string, string>
 
-    cssClassIdx: number
     cssAnimIdx: number
 
     shadowIdx: number
@@ -141,6 +145,10 @@ export interface BrushScope {
      * If create animates nodes.
      */
     animation?: boolean,
+    /**
+     * If create emphasis styles.
+     */
+    emphasis?: boolean,
 
     /**
      * If will update. Some optimization for string generation can't be applied.
@@ -164,8 +172,8 @@ export function createBrushScope(zrId: string): BrushScope {
 
         cssNodes: {},
         cssAnims: {},
+        cssStyleCache: {},
 
-        cssClassIdx: 0,
         cssAnimIdx: 0,
 
         shadowIdx: 0,

src/svg/cssAnimation.ts

@@ -10,6 +10,7 @@ import Animator from '../animation/Animator';
 import CompoundPath from '../graphic/CompoundPath';
 import { AnimationEasing } from '../animation/easing';
 import { createCubicEasingFunc } from '../animation/cubicEasing';
+import { getClassId } from './cssClassId';
 
 export const EASING_MAP: Record<string, string> = {
     // From https://easings.net/
@@ -355,7 +356,7 @@ export function createCSSAnimation(
     }
 
     if (cssAnimations.length) {
-        const className = scope.zrId + '-cls-' + scope.cssClassIdx++;
+        const className = scope.zrId + '-cls-' + getClassId();
         scope.cssNodes['.' + className] = {
             animation: cssAnimations.join(',')
         };

src/svg/cssClassId.ts

@@ -0,0 +1,5 @@
+let cssClassIdx = 0;
+
+export function getClassId() {
+    return cssClassIdx++;
+}

src/svg/cssEmphasis.ts

@@ -0,0 +1,73 @@
+import Displayable from '../graphic/Displayable';
+import { liftColor } from '../tool/color';
+import { BrushScope, SVGVNodeAttrs } from './core';
+import { getClassId } from './cssClassId';
+
+export function createCSSEmphasis(
+    el: Displayable,
+    attrs: SVGVNodeAttrs,
+    scope: BrushScope
+) {
+    if (!el.ignore) {
+        if (el.isSilent()) {
+            // If el is silent, it can not be hovered nor selected.
+            // So set pointer-events to pass through.
+            const style = {
+                'pointer-events': 'none'
+            };
+            setClassAttribute(style, attrs, scope, true);
+        }
+        else {
+            const emphasisStyle = el.states.emphasis && el.states.emphasis.style
+                ? el.states.emphasis.style
+                : {};
+            let fill = emphasisStyle.fill;
+            if (!fill) {
+                // No empahsis fill, lift color
+                const normalFill = el.style && el.style.fill;
+                const selectFill = el.states.select
+                    && el.states.select.style
+                    && el.states.select.style.fill;
+                const fromFill = el.currentStates.indexOf('select') >= 0
+                    ? (selectFill || normalFill)
+                    : normalFill;
+                if (fromFill) {
+                    fill = liftColor(fromFill);
+                }
+            }
+            let lineWidth = emphasisStyle.lineWidth;
+            if (lineWidth) {
+                // Symbols use transform to set size, so lineWidth
+                // should be divided by scaleX
+                const scaleX = (!emphasisStyle.strokeNoScale && el.transform)
+                    ? el.transform[0]
+                    : 1;
+                lineWidth = lineWidth / scaleX;
+            }
+            const style = {
+                cursor: 'pointer', // TODO: Should this be customized?
+            } as any;
+            if (fill) {
+                style.fill = fill;
+            }
+            if (emphasisStyle.stroke) {
+                style.stroke = emphasisStyle.stroke;
+            }
+            if (lineWidth) {
+                style['stroke-width'] = lineWidth;
+            }
+            setClassAttribute(style, attrs, scope, true);
+        }
+    }
+}
+
+function setClassAttribute(style: object, attrs: SVGVNodeAttrs, scope: BrushScope, withHover: boolean) {
+    const styleKey = JSON.stringify(style);
+    let className = scope.cssStyleCache[styleKey];
+    if (!className) {
+        className = scope.zrId + '-cls-' + getClassId();
+        scope.cssStyleCache[styleKey] = className;
+        scope.cssNodes['.' + className + (withHover ? ':hover' : '')] = style as any;
+    }
+    attrs.class = attrs.class ? (attrs.class + ' ' + className) : className;
+}

src/svg/graphic.ts

@@ -26,10 +26,10 @@ import { getLineHeight } from '../contain/text';
 import TSpan, { TSpanStyleProps } from '../graphic/TSpan';
 import SVGPathRebuilder from './SVGPathRebuilder';
 import mapStyleToAttrs from './mapStyleToAttrs';
-import { SVGVNodeAttrs, createVNode, SVGVNode, vNodeToString, BrushScope } from './core';
+import { SVGVNodeAttrs, createVNode, SVGVNode, vNodeToString, BrushScope, META_DATA_PREFIX } from './core';
 import { MatrixArray } from '../core/matrix';
 import Displayable from '../graphic/Displayable';
-import { assert, clone, isFunction, isString, logError, map, retrieve2 } from '../core/util';
+import { assert, clone, each, isFunction, isString, logError, map, retrieve2 } from '../core/util';
 import Polyline from '../graphic/shape/Polyline';
 import Polygon from '../graphic/shape/Polygon';
 import { GradientObject } from '../graphic/Gradient';
@@ -39,6 +39,8 @@ import { ImageLike } from '../core/types';
 import { createCSSAnimation } from './cssAnimation';
 import { hasSeparateFont, parseFontSize } from '../graphic/Text';
 import { DEFAULT_FONT, DEFAULT_FONT_FAMILY } from '../core/platform';
+import { createCSSEmphasis } from './cssEmphasis';
+import { getElementSSRData } from '../zrender';
 
 const round = Math.round;
 
@@ -61,6 +63,10 @@ function setStyleAttrs(attrs: SVGVNodeAttrs, style: AllStyleOption, el: Path | T
         else if (isFillStroke && isPattern(val)) {
             setPattern(el, attrs, key, scope);
         }
+        else if (isFillStroke && val === 'none') {
+            // When is none, it cannot be interacted when ssr
+            attrs[key] = 'transparent';
+        }
         else {
             attrs[key] = val;
         }
@@ -69,6 +75,19 @@ function setStyleAttrs(attrs: SVGVNodeAttrs, style: AllStyleOption, el: Path | T
     setShadow(el, attrs, scope);
 }
 
+function setMetaData(attrs: SVGVNodeAttrs, el: Path | TSpan | ZRImage) {
+    const metaData = getElementSSRData(el);
+    if (metaData) {
+        metaData.each((val, key) => {
+            attrs[(META_DATA_PREFIX + key).toLowerCase()]
+                = val + '';
+        });
+        if (el.isSilent()) {
+            attrs[META_DATA_PREFIX + 'silent'] = 'true';
+        }
+    }
+}
+
 function noRotateScale(m: MatrixArray) {
     return isAroundZero(m[0] - 1)
         && isAroundZero(m[1])
@@ -204,8 +223,10 @@ export function brushSVGPath(el: Path, scope: BrushScope) {
 
     setTransform(attrs, el.transform);
     setStyleAttrs(attrs, style, el, scope);
+    setMetaData(attrs, el);
 
     scope.animation && createCSSAnimation(el, attrs, scope);
+    scope.emphasis && createCSSEmphasis(el, attrs, scope);
 
     return createVNode(svgElType, el.id + '', attrs);
 }
@@ -248,6 +269,7 @@ export function brushSVGImage(el: ZRImage, scope: BrushScope) {
 
     setTransform(attrs, el.transform);
     setStyleAttrs(attrs, style, el, scope);
+    setMetaData(attrs, el);
 
     scope.animation && createCSSAnimation(el, attrs, scope);
 
@@ -319,6 +341,7 @@ export function brushSVGTSpan(el: TSpan, scope: BrushScope) {
     }
     setTransform(attrs, el.transform);
     setStyleAttrs(attrs, style, el, scope);
+    setMetaData(attrs, el);
 
     scope.animation && createCSSAnimation(el, attrs, scope);
 

src/tool/color.ts

@@ -1,4 +1,6 @@
 import LRU from '../core/LRU';
+import { extend, isGradientObject, isString, map } from '../core/util';
+import { GradientObject } from '../graphic/Gradient';
 
 const kCSSColorTable = {
     'transparent': [0, 0, 0, 0], 'aliceblue': [240, 248, 255, 1],
@@ -566,4 +568,28 @@ export function random(): string {
         Math.round(Math.random() * 255),
         Math.round(Math.random() * 255)
     ], 'rgb');
-}
+}
+
+const liftedColorCache = new LRU<string>(100);
+export function liftColor(color: GradientObject): GradientObject;
+export function liftColor(color: string): string;
+export function liftColor(color: string | GradientObject): string | GradientObject {
+    if (isString(color)) {
+        let liftedColor = liftedColorCache.get(color);
+        if (!liftedColor) {
+            liftedColor = lift(color, -0.1);
+            liftedColorCache.put(color, liftedColor);
+        }
+        return liftedColor;
+    }
+    else if (isGradientObject(color)) {
+        const ret = extend({}, color) as GradientObject;
+        ret.colorStops = map(color.colorStops, stop => ({
+            offset: stop.offset,
+            color: lift(stop.color, -0.1)
+        }));
+        return ret;
+    }
+    // Change nothing.
+    return color;
+}

src/zrender.ts

@@ -482,6 +482,23 @@ export function registerPainter(name: string, Ctor: PainterBaseCtor) {
     painterCtors[name] = Ctor;
 }
 
+export type ElementSSRData = zrUtil.HashMap<unknown>;
+export type ElementSSRDataGetter<T> = (el: Element) => zrUtil.HashMap<T>;
+
+let ssrDataGetter = function (el: Element): ElementSSRData {
+    return null;
+}
+
+export function getElementSSRData(el: Element): ElementSSRData {
+    if (typeof ssrDataGetter === 'function') {
+        return ssrDataGetter(el);
+    }
+}
+
+export function registerSSRDataGetter<T>(getter: ElementSSRDataGetter<T>) {
+    ssrDataGetter = getter;
+}
+
 /**
  * @type {string}
  */