fabric/dist/src/util/misc/projectStroke/StrokeLineCapProjections.mjs.map

Object model for HTML5 canvas, and SVG-to-canvas parser. Backed by jsdom and node-canvas.

{"version":3,"file":"StrokeLineCapProjections.mjs","names":[],"sources":["../../../../../src/util/misc/projectStroke/StrokeLineCapProjections.ts"],"sourcesContent":["import type { XY } from '../../../Point';\nimport { Point } from '../../../Point';\nimport { getOrthonormalVector, getUnitVector } from '../vectors';\nimport { StrokeLineJoinProjections } from './StrokeLineJoinProjections';\nimport { StrokeProjectionsBase } from './StrokeProjectionsBase';\nimport type { TProjection, TProjectStrokeOnPointsOptions } from './types';\n\n/**\n * class in charge of finding projections for each type of line cap for start/end of an open path\n * @see {@link [Open path projections at #8344](https://github.com/fabricjs/fabric.js/pull/8344#1-open-path)}\n *\n * Reference:\n * - MDN:\n *   - https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D/lineCap\n *   - https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute/stroke-linecap\n * - Spec: https://html.spec.whatwg.org/multipage/canvas.html#dom-context-2d-linecap-dev\n * - Playground to understand how the line joins works: https://hypertolosana.github.io/efficient-webgl-stroking/index.html\n * - View the calculated projections for each of the control points: https://codesandbox.io/s/project-stroke-points-with-context-to-trace-b8jc4j?file=/src/index.js\n */\nexport class StrokeLineCapProjections extends StrokeProjectionsBase {\n  /**\n   * edge point\n   */\n  declare A: Point;\n  /**\n   * point next to edge point\n   */\n  declare T: Point;\n\n  constructor(A: XY, T: XY, options: TProjectStrokeOnPointsOptions) {\n    super(options);\n    this.A = new Point(A);\n    this.T = new Point(T);\n  }\n\n  calcOrthogonalProjection(\n    from: Point,\n    to: Point,\n    magnitude: number = this.strokeProjectionMagnitude,\n  ) {\n    const vector = this.createSideVector(from, to);\n    return this.scaleUnitVector(getOrthonormalVector(vector), magnitude);\n  }\n\n  /**\n   * OPEN PATH START/END - Line cap: Butt\n   * Calculation: to find the projections, just find the points orthogonal to the stroke\n   *\n   * @see https://github.com/fabricjs/fabric.js/pull/8344#1-1-butt\n   */\n  projectButt() {\n    return [\n      this.projectOrthogonally(this.A, this.T, this.strokeProjectionMagnitude),\n      this.projectOrthogonally(this.A, this.T, -this.strokeProjectionMagnitude),\n    ];\n  }\n\n  /**\n   * OPEN PATH START/END - Line cap: Round\n   * Calculation: same as stroke line join `round`\n   *\n   * @see https://github.com/fabricjs/fabric.js/pull/8344#1-2-round\n   */\n  projectRound() {\n    const projections: Point[] = [];\n\n    if (!this.isSkewed() && this.A.eq(this.T)) {\n      /* 1 point case without `skew`\n        When `strokeUniform` is true, scaling has no effect.\n        So we divide by scale, to remove its effect.\n      */\n      const projection = new Point(1, 1)\n        .scalarMultiply(this.strokeProjectionMagnitude)\n        .multiply(this.strokeUniformScalar);\n      projections.push(\n        this.applySkew(this.A.add(projection)),\n        this.applySkew(this.A.subtract(projection)),\n      );\n    } else {\n      projections.push(\n        ...new StrokeLineJoinProjections(\n          this.A,\n          this.T,\n          this.T,\n          this.options,\n        ).projectRound(),\n      );\n    }\n\n    return projections;\n  }\n\n  /**\n   * OPEN PATH START/END - Line cap: Square\n   * Calculation: project a rectangle of points on the stroke in the opposite direction of the vector `AT`\n   *\n   * @see https://github.com/fabricjs/fabric.js/pull/8344#1-3-square\n   */\n  projectSquare() {\n    const projections: Point[] = [];\n\n    if (this.A.eq(this.T)) {\n      /* 1 point case without `skew`\n        When `strokeUniform` is true, scaling has no effect.\n        So we divide by scale, to remove its effect.\n      */\n      const projection = new Point(1, 1)\n        .scalarMultiply(this.strokeProjectionMagnitude)\n        .multiply(this.strokeUniformScalar);\n      projections.push(this.A.add(projection), this.A.subtract(projection));\n    } else {\n      const orthogonalProjection = this.calcOrthogonalProjection(\n        this.A,\n        this.T,\n        this.strokeProjectionMagnitude,\n      );\n      const strokePointingOut = this.scaleUnitVector(\n        getUnitVector(this.createSideVector(this.A, this.T)),\n        -this.strokeProjectionMagnitude,\n      );\n      const projectedA = this.A.add(strokePointingOut);\n      projections.push(\n        projectedA.add(orthogonalProjection),\n        projectedA.subtract(orthogonalProjection),\n      );\n    }\n\n    return projections.map((p) => this.applySkew(p));\n  }\n\n  protected projectPoints() {\n    switch (this.options.strokeLineCap) {\n      case 'round':\n        return this.projectRound();\n      case 'square':\n        return this.projectSquare();\n      default:\n        return this.projectButt();\n    }\n  }\n\n  public project(): TProjection[] {\n    return this.projectPoints().map((point) => ({\n      originPoint: this.A,\n      projectedPoint: point,\n    }));\n  }\n}\n"],"mappings":";;;;;;;;;;;;;;;;;AAmBA,IAAa,2BAAb,cAA8C,sBAAsB;CAUlE,YAAY,GAAO,GAAO,SAAwC;AAChE,QAAM,QAAQ;AACd,OAAK,IAAI,IAAI,MAAM,EAAE;AACrB,OAAK,IAAI,IAAI,MAAM,EAAE;;CAGvB,yBACE,MACA,IACA,YAAoB,KAAK,2BACzB;EACA,MAAM,SAAS,KAAK,iBAAiB,MAAM,GAAG;AAC9C,SAAO,KAAK,gBAAgB,qBAAqB,OAAO,EAAE,UAAU;;;;;;;;CAStE,cAAc;AACZ,SAAO,CACL,KAAK,oBAAoB,KAAK,GAAG,KAAK,GAAG,KAAK,0BAA0B,EACxE,KAAK,oBAAoB,KAAK,GAAG,KAAK,GAAG,CAAC,KAAK,0BAA0B,CAC1E;;;;;;;;CASH,eAAe;EACb,MAAM,cAAuB,EAAE;AAE/B,MAAI,CAAC,KAAK,UAAU,IAAI,KAAK,EAAE,GAAG,KAAK,EAAE,EAAE;GAKzC,MAAM,aAAa,IAAI,MAAM,GAAG,EAAE,CAC/B,eAAe,KAAK,0BAA0B,CAC9C,SAAS,KAAK,oBAAoB;AACrC,eAAY,KACV,KAAK,UAAU,KAAK,EAAE,IAAI,WAAW,CAAC,EACtC,KAAK,UAAU,KAAK,EAAE,SAAS,WAAW,CAAC,CAC5C;QAED,aAAY,KACV,GAAG,IAAI,0BACL,KAAK,GACL,KAAK,GACL,KAAK,GACL,KAAK,QACN,CAAC,cAAc,CACjB;AAGH,SAAO;;;;;;;;CAST,gBAAgB;EACd,MAAM,cAAuB,EAAE;AAE/B,MAAI,KAAK,EAAE,GAAG,KAAK,EAAE,EAAE;GAKrB,MAAM,aAAa,IAAI,MAAM,GAAG,EAAE,CAC/B,eAAe,KAAK,0BAA0B,CAC9C,SAAS,KAAK,oBAAoB;AACrC,eAAY,KAAK,KAAK,EAAE,IAAI,WAAW,EAAE,KAAK,EAAE,SAAS,WAAW,CAAC;SAChE;GACL,MAAM,uBAAuB,KAAK,yBAChC,KAAK,GACL,KAAK,GACL,KAAK,0BACN;GACD,MAAM,oBAAoB,KAAK,gBAC7B,cAAc,KAAK,iBAAiB,KAAK,GAAG,KAAK,EAAE,CAAC,EACpD,CAAC,KAAK,0BACP;GACD,MAAM,aAAa,KAAK,EAAE,IAAI,kBAAkB;AAChD,eAAY,KACV,WAAW,IAAI,qBAAqB,EACpC,WAAW,SAAS,qBAAqB,CAC1C;;AAGH,SAAO,YAAY,KAAK,MAAM,KAAK,UAAU,EAAE,CAAC;;CAGlD,gBAA0B;AACxB,UAAQ,KAAK,QAAQ,eAArB;GACE,KAAK,QACH,QAAO,KAAK,cAAc;GAC5B,KAAK,SACH,QAAO,KAAK,eAAe;GAC7B,QACE,QAAO,KAAK,aAAa;;;CAI/B,UAAgC;AAC9B,SAAO,KAAK,eAAe,CAAC,KAAK,WAAW;GAC1C,aAAa,KAAK;GAClB,gBAAgB;GACjB,EAAE"}