{"version":3,"file":"skew.min.mjs","names":[],"sources":["../../../src/controls/skew.ts"],"sourcesContent":["import type {\n  ControlCursorCallback,\n  TPointerEvent,\n  Transform,\n  TransformActionHandler,\n} from '../EventTypeDefs';\nimport { resolveOrigin } from '../util/misc/resolveOrigin';\nimport { Point } from '../Point';\nimport type { TAxis, TAxisKey } from '../typedefs';\nimport {\n  degreesToRadians,\n  radiansToDegrees,\n} from '../util/misc/radiansDegreesConversion';\nimport {\n  findCornerQuadrant,\n  getLocalPoint,\n  isLocked,\n  NOT_ALLOWED_CURSOR,\n} from './util';\nimport { wrapWithFireEvent } from './wrapWithFireEvent';\nimport { wrapWithFixedAnchor } from './wrapWithFixedAnchor';\nimport {\n  CENTER,\n  SCALE_X,\n  SCALE_Y,\n  SKEWING,\n  SKEW_X,\n  SKEW_Y,\n} from '../constants';\n\nexport type SkewTransform = Transform & { skewingSide: -1 | 1 };\n\nconst AXIS_KEYS: Record<\n  TAxis,\n  {\n    counterAxis: TAxis;\n    scale: TAxisKey<'scale'>;\n    skew: TAxisKey<'skew'>;\n    lockSkewing: TAxisKey<'lockSkewing'>;\n    origin: TAxisKey<'origin'>;\n    flip: TAxisKey<'flip'>;\n  }\n> = {\n  x: {\n    counterAxis: 'y',\n    scale: SCALE_X,\n    skew: SKEW_X,\n    lockSkewing: 'lockSkewingX',\n    origin: 'originX',\n    flip: 'flipX',\n  },\n  y: {\n    counterAxis: 'x',\n    scale: SCALE_Y,\n    skew: SKEW_Y,\n    lockSkewing: 'lockSkewingY',\n    origin: 'originY',\n    flip: 'flipY',\n  },\n};\n\nconst skewMap = ['ns', 'nesw', 'ew', 'nwse'];\n\n/**\n * return the correct cursor style for the skew action\n * @param {Event} eventData the javascript event that is causing the scale\n * @param {Control} control the control that is interested in the action\n * @param {FabricObject} fabricObject the fabric object that is interested in the action\n * @return {String} a valid css string for the cursor\n */\nexport const skewCursorStyleHandler: ControlCursorCallback = (\n  eventData,\n  control,\n  fabricObject,\n  coord,\n) => {\n  if (control.x !== 0 && isLocked(fabricObject, 'lockSkewingY')) {\n    return NOT_ALLOWED_CURSOR;\n  }\n  if (control.y !== 0 && isLocked(fabricObject, 'lockSkewingX')) {\n    return NOT_ALLOWED_CURSOR;\n  }\n  const n = findCornerQuadrant(fabricObject, control, coord) % 4;\n  return `${skewMap[n]}-resize`;\n};\n\n/**\n * Since skewing is applied before scaling, calculations are done in a scaleless plane\n * @see https://github.com/fabricjs/fabric.js/pull/8380\n */\nfunction skewObject(\n  axis: TAxis,\n  { target, ex, ey, skewingSide, ...transform }: SkewTransform,\n  pointer: Point,\n) {\n  const { skew: skewKey } = AXIS_KEYS[axis],\n    offset = pointer\n      .subtract(new Point(ex, ey))\n      .divide(new Point(target.scaleX, target.scaleY))[axis],\n    skewingBefore = target[skewKey],\n    skewingStart = transform[skewKey],\n    shearingStart = Math.tan(degreesToRadians(skewingStart)),\n    // let a, b be the size of target\n    // let a' be the value of a after applying skewing\n    // then:\n    // a' = a + b * skewA => skewA = (a' - a) / b\n    // the value b is tricky since skewY is applied before skewX\n    b =\n      axis === 'y'\n        ? target._getTransformedDimensions({\n            scaleX: 1,\n            scaleY: 1,\n            // since skewY is applied before skewX, b (=width) is not affected by skewX\n            skewX: 0,\n          }).x\n        : target._getTransformedDimensions({\n            scaleX: 1,\n            scaleY: 1,\n          }).y;\n\n  const shearing =\n    (2 * offset * skewingSide) /\n      // we max out fractions to safeguard from asymptotic behavior\n      Math.max(b, 1) +\n    // add starting state\n    shearingStart;\n\n  const skewing = radiansToDegrees(Math.atan(shearing));\n\n  target.set(skewKey, skewing);\n  const changed = skewingBefore !== target[skewKey];\n\n  if (changed && axis === 'y') {\n    // we don't want skewing to affect scaleX\n    // so we factor it by the inverse skewing diff to make it seem unchanged to the viewer\n    const { skewX, scaleX } = target,\n      dimBefore = target._getTransformedDimensions({ skewY: skewingBefore }),\n      dimAfter = target._getTransformedDimensions(),\n      compensationFactor = skewX !== 0 ? dimBefore.x / dimAfter.x : 1;\n    compensationFactor !== 1 &&\n      target.set(SCALE_X, compensationFactor * scaleX);\n  }\n\n  return changed;\n}\n\n/**\n * Wrapped Action handler for skewing on a given axis, takes care of the\n * skew direction and determines the correct transform origin for the anchor point\n * @param {Event} eventData javascript event that is doing the transform\n * @param {Object} transform javascript object containing a series of information around the current transform\n * @param {number} x current mouse x position, canvas normalized\n * @param {number} y current mouse y position, canvas normalized\n * @return {Boolean} true if some change happened\n */\nfunction skewHandler(\n  axis: TAxis,\n  eventData: TPointerEvent,\n  transform: Transform,\n  x: number,\n  y: number,\n) {\n  const { target } = transform,\n    {\n      counterAxis,\n      origin: originKey,\n      lockSkewing: lockSkewingKey,\n      skew: skewKey,\n      flip: flipKey,\n    } = AXIS_KEYS[axis];\n  if (isLocked(target, lockSkewingKey)) {\n    return false;\n  }\n\n  const { origin: counterOriginKey, flip: counterFlipKey } =\n      AXIS_KEYS[counterAxis],\n    counterOriginFactor =\n      resolveOrigin(transform[counterOriginKey]) *\n      (target[counterFlipKey] ? -1 : 1),\n    // if the counter origin is top/left (= -0.5) then we are skewing x/y values on the bottom/right side of target respectively.\n    // if the counter origin is bottom/right (= 0.5) then we are skewing x/y values on the top/left side of target respectively.\n    // skewing direction on the top/left side of target is OPPOSITE to the direction of the movement of the pointer,\n    // so we factor skewing direction by this value.\n    skewingSide = (-Math.sign(counterOriginFactor) *\n      (target[flipKey] ? -1 : 1)) as 1 | -1,\n    skewingDirection =\n      ((target[skewKey] === 0 &&\n        // in case skewing equals 0 we use the pointer offset from target center to determine the direction of skewing\n        getLocalPoint(transform, CENTER, CENTER, x, y)[axis] > 0) ||\n      // in case target has skewing we use that as the direction\n      target[skewKey] > 0\n        ? 1\n        : -1) * skewingSide,\n    // anchor to the opposite side of the skewing direction\n    // normalize value from [-1, 1] to origin value [0, 1]\n    origin = -skewingDirection * 0.5 + 0.5;\n\n  const finalHandler = wrapWithFireEvent<SkewTransform>(\n    SKEWING,\n    wrapWithFixedAnchor((eventData, transform, x, y) =>\n      skewObject(axis, transform, new Point(x, y)),\n    ),\n  );\n\n  return finalHandler(\n    eventData,\n    {\n      ...transform,\n      [originKey]: origin,\n      skewingSide,\n    },\n    x,\n    y,\n  );\n}\n\n/**\n * Wrapped Action handler for skewing on the X axis, takes care of the\n * skew direction and determines the correct transform origin for the anchor point\n * @param {Event} eventData javascript event that is doing the transform\n * @param {Object} transform javascript object containing a series of information around the current transform\n * @param {number} x current mouse x position, canvas normalized\n * @param {number} y current mouse y position, canvas normalized\n * @return {Boolean} true if some change happened\n */\nexport const skewHandlerX: TransformActionHandler = (\n  eventData,\n  transform,\n  x,\n  y,\n) => {\n  return skewHandler('x', eventData, transform, x, y);\n};\n\n/**\n * Wrapped Action handler for skewing on the Y axis, takes care of the\n * skew direction and determines the correct transform origin for the anchor point\n * @param {Event} eventData javascript event that is doing the transform\n * @param {Object} transform javascript object containing a series of information around the current transform\n * @param {number} x current mouse x position, canvas normalized\n * @param {number} y current mouse y position, canvas normalized\n * @return {Boolean} true if some change happened\n */\nexport const skewHandlerY: TransformActionHandler = (\n  eventData,\n  transform,\n  x,\n  y,\n) => {\n  return skewHandler('y', eventData, transform, x, y);\n};\n"],"mappings":"qiBAgCA,MAAM,EAUF,CACF,EAAG,CACD,YAAa,IACb,MAAO,EACP,KAAM,EACN,YAAa,eACb,OAAQ,UACR,KAAM,QAAA,CAER,EAAG,CACD,YAAa,IACb,MAAO,EACP,KAAM,EACN,YAAa,eACb,OAAQ,UACR,KAAM,QAAA,CAAA,CAIJ,EAAU,CAAC,KAAM,OAAQ,KAAM,OAAA,CASxB,GACX,EACA,EACA,EACA,IAEI,EAAQ,IAAM,GAAK,EAAS,EAAc,eAAA,EAG1C,EAAQ,IAAM,GAAK,EAAS,EAAc,eAAA,CAFrC,EAMF,GAAG,EADA,EAAmB,EAAc,EAAS,EAAA,CAAS,GAAA,SAyE/D,SAAS,EACP,EACA,EACA,EACA,EACA,EAAA,CAEA,GAAA,CAAM,OAAE,GAAW,EAAA,CACjB,YACE,EACA,OAAQ,EACR,YAAa,EACb,KAAM,EACN,KAAM,GACJ,EAAU,GAChB,GAAI,EAAS,EAAQ,EAAA,CACnB,MAAA,CAAO,EAGT,GAAA,CAAQ,OAAQ,EAAkB,KAAM,GACpC,EAAU,GACZ,EACE,EAAc,EAAU,GAAA,EACvB,EAAO,GAAA,GAAuB,GAKjC,EAAA,CAAgB,KAAK,KAAK,EAAA,EACvB,EAAO,GAAA,GAAgB,GAW1B,EAAA,EATI,EAAO,KAAa,GAEpB,EAAc,EAAA,SAAA,SAA2B,EAAG,EAAA,CAAG,GAAQ,GAEzD,EAAO,GAAW,EACd,EAAA,IACM,EAGiB,GAAM,GASrC,OAPqB,EACnB,EACA,GAAqB,EAAW,EAAW,EAAG,IA7GlD,SACE,EAAA,CACA,OAAE,EAAA,GAAQ,EAAA,GAAI,EAAA,YAAI,EAAA,GAAgB,GAClC,EAAA,CAEA,GAAA,CAAQ,KAAM,GAAY,EAAU,GAClC,EAAS,EACN,SAAS,IAAI,EAAM,EAAI,EAAA,CAAA,CACvB,OAAO,IAAI,EAAM,EAAO,OAAQ,EAAO,OAAA,CAAA,CAAS,GACnD,EAAgB,EAAO,GACvB,EAAe,EAAU,GACzB,EAAgB,KAAK,IAAI,EAAiB,EAAA,CAAA,CAM1C,EACE,IAAS,IACL,EAAO,0BAA0B,CAC/B,OAAQ,EACR,OAAQ,EAER,MAAO,EAAA,CAAA,CACN,EACH,EAAO,0BAA0B,CAC/B,OAAQ,EACR,OAAQ,EAAA,CAAA,CACP,EAEL,EACH,EAAI,EAAS,EAEZ,KAAK,IAAI,EAAG,EAAA,CAEd,EAEI,EAAU,EAAiB,KAAK,KAAK,EAAA,CAAA,CAE3C,EAAO,IAAI,EAAS,EAAA,CACpB,IAAM,EAAU,IAAkB,EAAO,GAEzC,GAAI,GAAW,IAAS,IAAK,CAG3B,GAAA,CAAM,MAAE,EAAA,OAAO,GAAW,EACxB,EAAY,EAAO,0BAA0B,CAAE,MAAO,EAAA,CAAA,CACtD,EAAW,EAAO,2BAAA,CAClB,EAAqB,IAAU,EAA+B,EAA3B,EAAU,EAAI,EAAS,EAC5D,IAAuB,GACrB,EAAO,IAAA,SAAa,EAAqB,EAAA,CAG7C,OAAO,GAyDQ,EAAM,EAAW,IAAI,EAAM,EAAG,EAAA,CAAA,CAAA,CAHxB,CAQnB,EACA,CAAA,GACK,GACF,GAAY,EACb,YAAA,EAAA,CAEF,EACA,EAAA,CAaJ,MAAa,GACX,EACA,EACA,EACA,IAEO,EAAY,IAAK,EAAW,EAAW,EAAG,EAAA,CAYtC,GACX,EACA,EACA,EACA,IAEO,EAAY,IAAK,EAAW,EAAW,EAAG,EAAA,CAAA,OAAA,KAAA,uBAAA,KAAA,aAAA,KAAA"}