add initial marp implementation with sample content and build configuration

node_modules/mathjax-full/ts/output/common/Wrappers/mfrac.ts

@@ -0,0 +1,302 @@
+/*************************************************************
+ *
+ *  Copyright (c) 2017-2022 The MathJax Consortium
+ *
+ *  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.
+ */
+
+/**
+ * @fileoverview  Implements the CommonMfrac wrapper mixin for the MmlMfrac object
+ *
+ * @author dpvc@mathjax.org (Davide Cervone)
+ */
+
+import {AnyWrapper, WrapperConstructor, Constructor} from '../Wrapper.js';
+import {CommonMo} from './mo.js';
+import {BBox} from '../../../util/BBox.js';
+import {DIRECTION} from '../FontData.js';
+
+/*****************************************************************/
+/**
+ * The CommonMfrac interface
+ */
+export interface CommonMfrac extends AnyWrapper {
+  /**
+   * @param {BBox} bbox        The buonding box to modify
+   * @param {boolean} display  True for display-mode fractions
+   * @param {number} t         The thickness of the line
+   */
+  getFractionBBox(bbox: BBox, display: boolean, t: number): void;
+
+  /**
+   * @param {boolean} display  True for display-mode fractions
+   * @param {number} t         The thickness of the line
+   * @return {Object}          The expanded rule thickness (T), and baseline offsets
+   *                             for numerator and denomunator (u and v)
+   */
+  getTUV(display: boolean, t: number): {T: number, u: number, v: number};
+
+  /**
+   * @param {BBox} bbox        The bounding box to modify
+   * @param {boolean} display  True for display-mode fractions
+   */
+  getAtopBBox(bbox: BBox, display: boolean): void;
+
+  /**
+   * @param {boolean} display  True for diplay-mode fractions
+   * @return {Object}
+   *    The vertical offsets of the numerator (u), the denominator (v),
+   *    the separation between the two, and the bboxes themselves.
+   */
+  getUVQ(display: boolean): {u: number, v: number, q: number, nbox: BBox, dbox: BBox};
+
+  /**
+   * @param {BBox} bbox        The boundng box to modify
+   * @param {boolean} display  True for display-mode fractions
+   */
+  getBevelledBBox(bbox: BBox, display: boolean): void;
+
+  /**
+   * @param {boolean} display  True for display-style fractions
+   * @return {Object}          The height (H) of the bevel, horizontal offest (delta)
+   *                             vertical offsets (u and v) of the parts, and
+   *                             bounding boxes of the parts.
+   */
+  getBevelData(display: boolean): {H: number, delta: number, u: number, v: number, nbox: BBox, dbox: BBox};
+
+  /**
+   * @return {boolean}   True if in display mode, false otherwise
+   */
+  isDisplay(): boolean;
+}
+
+/**
+ * Shorthand for the CommonMfrac constructor
+ */
+export type MfracConstructor = Constructor<CommonMfrac>;
+
+/*****************************************************************/
+/**
+ * The CommonMfrac wrapper mixin for the MmlMfrac object
+ *
+ * @template T  The Wrapper class constructor type
+ */
+export function CommonMfracMixin<T extends WrapperConstructor>(Base: T): MfracConstructor & T {
+
+  return class extends Base {
+
+    /**
+     * Wrapper for <mo> to use for bevelled fraction
+     */
+    public bevel: CommonMo = null;
+
+    /**
+     * Padding around fractions
+     */
+    public pad: number;
+
+    /************************************************/
+
+    /**
+     * @override
+     * @constructor
+     */
+    constructor(...args: any[]) {
+      super(...args);
+      this.pad = (this.node.getProperty('withDelims') as boolean ? 0 : this.font.params.nulldelimiterspace);
+      //
+      //  create internal bevel mo element
+      //
+      if (this.node.attributes.get('bevelled')) {
+        const {H} = this.getBevelData(this.isDisplay());
+        const bevel = this.bevel = this.createMo('/') as CommonMo;
+        bevel.node.attributes.set('symmetric', true);
+        bevel.canStretch(DIRECTION.Vertical);
+        bevel.getStretchedVariant([H], true);
+      }
+    }
+
+    /**
+     * @override
+     */
+    public computeBBox(bbox: BBox, recompute: boolean = false) {
+      bbox.empty();
+      const {linethickness, bevelled} = this.node.attributes.getList('linethickness', 'bevelled');
+      const display = this.isDisplay();
+      let w = null as (number | null);
+      if (bevelled) {
+        this.getBevelledBBox(bbox, display);
+      } else {
+        const thickness = this.length2em(String(linethickness), .06);
+        w = -2 * this.pad;
+        if (thickness === 0) {
+          this.getAtopBBox(bbox, display);
+        } else {
+          this.getFractionBBox(bbox, display, thickness);
+          w -= .2;
+        }
+        w += bbox.w;
+      }
+      bbox.clean();
+      this.setChildPWidths(recompute, w);
+    }
+
+    /************************************************/
+
+    /**
+     * @param {BBox} bbox        The buonding box to modify
+     * @param {boolean} display  True for display-mode fractions
+     * @param {number} t         The thickness of the line
+     */
+    public getFractionBBox(bbox: BBox, display: boolean, t: number) {
+      const nbox = this.childNodes[0].getOuterBBox();
+      const dbox = this.childNodes[1].getOuterBBox();
+      const tex = this.font.params;
+      const a = tex.axis_height;
+      const {T, u, v} = this.getTUV(display, t);
+      bbox.combine(nbox, 0, a + T + Math.max(nbox.d * nbox.rscale, u));
+      bbox.combine(dbox, 0, a - T - Math.max(dbox.h * dbox.rscale, v));
+      bbox.w += 2 * this.pad + .2;
+    }
+
+    /**
+     * @param {boolean} display  True for display-mode fractions
+     * @param {number} t         The thickness of the line
+     * @return {Object}          The expanded rule thickness (T), and baseline offsets
+     *                             for numerator and denomunator (u and v)
+     */
+    public getTUV(display: boolean, t: number): {T: number, u: number, v: number} {
+      const tex = this.font.params;
+      const a = tex.axis_height;
+      const T = (display ? 3.5 : 1.5) * t;
+      return {T: (display ? 3.5 : 1.5) * t,
+              u: (display ? tex.num1 : tex.num2) - a - T,
+              v: (display ? tex.denom1 : tex.denom2) + a - T};
+    }
+
+    /************************************************/
+
+    /**
+     * @param {BBox} bbox        The bounding box to modify
+     * @param {boolean} display  True for display-mode fractions
+     */
+    public getAtopBBox(bbox: BBox, display: boolean) {
+      const {u, v, nbox, dbox} = this.getUVQ(display);
+      bbox.combine(nbox, 0, u);
+      bbox.combine(dbox, 0, -v);
+      bbox.w += 2 * this.pad;
+    }
+
+    /**
+     * @param {boolean} display  True for diplay-mode fractions
+     * @return {Object}
+     *    The vertical offsets of the numerator (u), the denominator (v),
+     *    the separation between the two, and the bboxes themselves.
+     */
+    public getUVQ(display: boolean): {u: number, v: number, q: number, nbox: BBox, dbox: BBox} {
+      const nbox = this.childNodes[0].getOuterBBox();
+      const dbox = this.childNodes[1].getOuterBBox();
+      const tex = this.font.params;
+      //
+      //  Initial offsets (u, v)
+      //  Minimum separation (p)
+      //  Actual separation with initial positions (q)
+      //
+      let [u, v] = (display ? [tex.num1, tex.denom1] : [tex.num3, tex.denom2]);
+      let p = (display ? 7 : 3) * tex.rule_thickness;
+      let q = (u - nbox.d * nbox.scale) - (dbox.h * dbox.scale - v);
+      //
+      //  If actual separation is less than minimum, move them farther apart
+      //
+      if (q < p) {
+        u += (p - q) / 2;
+        v += (p - q) / 2;
+        q = p;
+      }
+      return {u, v, q, nbox, dbox};
+    }
+
+    /************************************************/
+
+    /**
+     * @param {BBox} bbox        The boundng box to modify
+     * @param {boolean} display  True for display-mode fractions
+     */
+    public getBevelledBBox(bbox: BBox, display: boolean) {
+      const {u, v, delta, nbox, dbox} = this.getBevelData(display);
+      const lbox = this.bevel.getOuterBBox();
+      bbox.combine(nbox, 0, u);
+      bbox.combine(lbox, bbox.w - delta / 2, 0);
+      bbox.combine(dbox, bbox.w - delta / 2, v);
+    }
+
+    /**
+     * @param {boolean} display  True for display-style fractions
+     * @return {Object}          The height (H) of the bevel, horizontal offest (delta)
+     *                             vertical offsets (u and v) of the parts, and
+     *                             bounding boxes of the parts.
+     */
+    public getBevelData(display: boolean): {
+      H: number, delta: number, u: number, v: number, nbox: BBox, dbox: BBox
+    } {
+      const nbox = this.childNodes[0].getOuterBBox();
+      const dbox = this.childNodes[1].getOuterBBox();
+      const delta = (display ? .4 : .15);
+      const H = Math.max(nbox.scale * (nbox.h + nbox.d), dbox.scale * (dbox.h + dbox.d)) + 2 * delta;
+      const a = this.font.params.axis_height;
+      const u = nbox.scale * (nbox.d - nbox.h) / 2 + a + delta;
+      const v = dbox.scale * (dbox.d - dbox.h) / 2 + a - delta;
+      return {H, delta, u, v, nbox, dbox};
+    }
+
+    /************************************************/
+
+    /**
+     * @override
+     */
+    public canStretch(_direction: DIRECTION) {
+      return false;
+    }
+
+    /**
+     * @return {boolean}   True if in display mode, false otherwise
+     */
+    public isDisplay(): boolean {
+      const {displaystyle, scriptlevel} = this.node.attributes.getList('displaystyle', 'scriptlevel');
+      return displaystyle && scriptlevel === 0;
+    }
+
+    /**
+     * @override
+     */
+    public getWrapWidth(i: number) {
+      const attributes = this.node.attributes;
+      if (attributes.get('bevelled')) {
+        return this.childNodes[i].getOuterBBox().w;
+      }
+      const w = this.getBBox().w;
+      const thickness = this.length2em(attributes.get('linethickness'));
+      return w - (thickness ? .2 : 0) -  2 * this.pad;
+    }
+
+    /**
+     * @override
+     */
+    public getChildAlign(i: number) {
+      const attributes = this.node.attributes;
+      return (attributes.get('bevelled') ? 'left' : attributes.get(['numalign', 'denomalign'][i]) as string);
+    }
+
+  };
+
+}