tldraw/lib/shape-utils/arrow.tsx
2021-06-18 16:31:46 +01:00

495 lines
12 KiB
TypeScript

import { uniqueId } from 'utils/utils'
import vec from 'utils/vec'
import {
getSvgPathFromStroke,
rng,
getBoundsFromPoints,
translateBounds,
pointsBetween,
} from 'utils/utils'
import { ArrowShape, Bounds, ShapeHandle, ShapeType } from 'types'
import { registerShapeUtils } from './index'
import { circleFromThreePoints, isAngleBetween } from 'utils/utils'
import { pointInBounds } from 'utils/bounds'
import {
intersectArcBounds,
intersectLineSegmentBounds,
} from 'utils/intersections'
import { pointInCircle } from 'utils/hitTests'
import { defaultStyle, getShapeStyle } from 'lib/shape-styles'
import getStroke from 'perfect-freehand'
const ctpCache = new WeakMap<ArrowShape['handles'], number[]>()
const pathCache = new WeakMap<ArrowShape, string>([])
function getCtp(shape: ArrowShape) {
if (!ctpCache.has(shape.handles)) {
const { start, end, bend } = shape.handles
ctpCache.set(
shape.handles,
circleFromThreePoints(start.point, end.point, bend.point)
)
}
return ctpCache.get(shape.handles)
}
const arrow = registerShapeUtils<ArrowShape>({
boundsCache: new WeakMap([]),
create(props) {
const {
point = [0, 0],
points = [
[0, 0],
[0, 1],
],
handles = {
start: {
id: 'start',
index: 0,
point: [0, 0],
},
end: {
id: 'end',
index: 1,
point: [1, 1],
},
bend: {
id: 'bend',
index: 2,
point: [0.5, 0.5],
},
},
} = props
return {
id: uniqueId(),
seed: Math.random(),
type: ShapeType.Arrow,
isGenerated: false,
name: 'Arrow',
parentId: 'page1',
childIndex: 0,
point,
rotation: 0,
isAspectRatioLocked: false,
isLocked: false,
isHidden: false,
bend: 0,
points,
handles,
decorations: {
start: null,
end: null,
middle: null,
},
...props,
style: {
...defaultStyle,
...props.style,
isFilled: false,
},
}
},
render(shape) {
const { id, bend, handles } = shape
const { start, end, bend: _bend } = handles
const arrowDist = vec.dist(start.point, end.point)
const showCircle = !vec.isEqual(
_bend.point,
vec.med(start.point, end.point)
)
const style = getShapeStyle(shape.style)
let body: JSX.Element
if (showCircle) {
if (!ctpCache.has(handles)) {
ctpCache.set(
handles,
circleFromThreePoints(start.point, end.point, _bend.point)
)
}
const circle = getCtp(shape)
if (!pathCache.has(shape)) {
renderPath(
shape,
vec.angle([circle[0], circle[1]], end.point) -
vec.angle(start.point, end.point) +
(Math.PI / 2) * (bend > 0 ? 0.98 : -0.98)
)
}
const path = pathCache.get(shape)
body = (
<>
<path
d={getArrowArcPath(start, end, circle, bend)}
fill="none"
strokeWidth={(+style.strokeWidth * 1.85).toString()}
strokeLinecap="round"
/>
<path d={path} strokeWidth={+style.strokeWidth * 1.5} />
</>
)
} else {
if (!pathCache.has(shape)) {
renderPath(shape)
}
const path = pathCache.get(shape)
body = <path d={path} />
}
return <g id={id}>{body}</g>
},
rotateBy(shape, delta) {
const { start, end, bend } = shape.handles
const mp = vec.med(start.point, end.point)
start.point = vec.rotWith(start.point, mp, delta)
end.point = vec.rotWith(end.point, mp, delta)
bend.point = vec.rotWith(bend.point, mp, delta)
this.onHandleChange(shape, shape.handles)
return this
},
rotateTo(shape, rotation, delta) {
const { start, end, bend } = shape.handles
const mp = vec.med(start.point, end.point)
start.point = vec.rotWith(start.point, mp, delta)
end.point = vec.rotWith(end.point, mp, delta)
bend.point = vec.rotWith(bend.point, mp, delta)
this.onHandleChange(shape, shape.handles)
return this
},
getBounds(shape) {
if (!this.boundsCache.has(shape)) {
const { start, end } = shape.handles
this.boundsCache.set(shape, getBoundsFromPoints([start.point, end.point]))
}
return translateBounds(this.boundsCache.get(shape), shape.point)
},
getRotatedBounds(shape) {
const { start, end } = shape.handles
return translateBounds(
getBoundsFromPoints([start.point, end.point], shape.rotation),
shape.point
)
},
getCenter(shape) {
const { start, end } = shape.handles
return vec.add(shape.point, vec.med(start.point, end.point))
},
hitTest(shape, point) {
const { start, end, bend } = shape.handles
if (shape.bend === 0) {
return (
vec.distanceToLineSegment(
start.point,
end.point,
vec.sub(point, shape.point)
) < 4
)
}
const [cx, cy, r] = getCtp(shape)
return !pointInCircle(point, vec.add(shape.point, [cx, cy]), r - 4)
},
hitTestBounds(this, shape, brushBounds) {
const { start, end, bend } = shape.handles
const sp = vec.add(shape.point, start.point)
const ep = vec.add(shape.point, end.point)
if (pointInBounds(sp, brushBounds) || pointInBounds(ep, brushBounds)) {
return true
}
if (vec.isEqual(vec.med(start.point, end.point), bend.point)) {
return intersectLineSegmentBounds(sp, ep, brushBounds).length > 0
} else {
const [cx, cy, r] = getCtp(shape)
const cp = vec.add(shape.point, [cx, cy])
return intersectArcBounds(sp, ep, cp, r, brushBounds).length > 0
}
},
transform(shape, bounds, { initialShape, scaleX, scaleY }) {
const initialShapeBounds = this.getBounds(initialShape)
shape.point = [bounds.minX, bounds.minY]
shape.points = shape.points.map((_, i) => {
const [x, y] = initialShape.points[i]
let nw = x / initialShapeBounds.width
let nh = y / initialShapeBounds.height
if (i === 1) {
let [x0, y0] = initialShape.points[0]
if (x0 === x) nw = 1
if (y0 === y) nh = 1
}
return [
bounds.width * (scaleX < 0 ? 1 - nw : nw),
bounds.height * (scaleY < 0 ? 1 - nh : nh),
]
})
const { start, end, bend } = shape.handles
start.point = shape.points[0]
end.point = shape.points[1]
bend.point = getBendPoint(shape)
shape.points = [shape.handles.start.point, shape.handles.end.point]
return this
},
onHandleChange(shape, handles) {
// const oldBounds = this.getRotatedBounds(shape)
// const prevCenter = getBoundsCenter(oldBounds)
for (let id in handles) {
const handle = handles[id]
shape.handles[handle.id] = handle
if (handle.index < 2) {
shape.points[handle.index] = handle.point
}
const { start, end, bend } = shape.handles
const dist = vec.dist(start.point, end.point)
if (handle.id === 'bend') {
const midPoint = vec.med(start.point, end.point)
const u = vec.uni(vec.vec(start.point, end.point))
const ap = vec.add(midPoint, vec.mul(vec.per(u), dist / 2))
const bp = vec.sub(midPoint, vec.mul(vec.per(u), dist / 2))
bend.point = vec.nearestPointOnLineSegment(ap, bp, bend.point, true)
shape.bend = vec.dist(bend.point, midPoint) / (dist / 2)
const sa = vec.angle(end.point, start.point)
const la = sa - Math.PI / 2
if (isAngleBetween(sa, la, vec.angle(end.point, bend.point))) {
shape.bend *= -1
}
}
}
shape.handles.bend.point = getBendPoint(shape)
// const newBounds = this.getRotatedBounds(shape)
// const newCenter = getBoundsCenter(newBounds)
// shape.point = vec.add(shape.point, vec.neg(vec.sub(newCenter, prevCenter)))
return this
},
onSessionComplete(shape) {
const bounds = this.getBounds(shape)
const offset = vec.sub([bounds.minX, bounds.minY], shape.point)
this.translateTo(shape, vec.add(shape.point, offset))
const { start, end, bend } = shape.handles
start.point = vec.sub(start.point, offset)
end.point = vec.sub(end.point, offset)
bend.point = vec.sub(bend.point, offset)
return this
},
applyStyles(shape, style) {
Object.assign(shape.style, style)
shape.style.isFilled = false
return this
},
canStyleFill: false,
})
export default arrow
function getArrowArcPath(
start: ShapeHandle,
end: ShapeHandle,
circle: number[],
bend: number
) {
return [
'M',
start.point[0],
start.point[1],
'A',
circle[2],
circle[2],
0,
0,
bend < 0 ? 0 : 1,
end.point[0],
end.point[1],
].join(' ')
}
function getBendPoint(shape: ArrowShape) {
const { start, end } = shape.handles
const dist = vec.dist(start.point, end.point)
const midPoint = vec.med(start.point, end.point)
const bendDist = (dist / 2) * shape.bend
const u = vec.uni(vec.vec(start.point, end.point))
return Math.abs(bendDist) < 10
? midPoint
: vec.add(midPoint, vec.mul(vec.per(u), bendDist))
}
function getResizeOffset(a: Bounds, b: Bounds) {
const { minX: x0, minY: y0, width: w0, height: h0 } = a
const { minX: x1, minY: y1, width: w1, height: h1 } = b
let delta: number[]
if (h0 === h1 && w0 !== w1) {
if (x0 !== x1) {
// moving left edge, pin right edge
delta = vec.sub([x1, y1 + h1 / 2], [x0, y0 + h0 / 2])
} else {
// moving right edge, pin left edge
delta = vec.sub([x1 + w1, y1 + h1 / 2], [x0 + w0, y0 + h0 / 2])
}
} else if (h0 !== h1 && w0 === w1) {
if (y0 !== y1) {
// moving top edge, pin bottom edge
delta = vec.sub([x1 + w1 / 2, y1], [x0 + w0 / 2, y0])
} else {
// moving bottom edge, pin top edge
delta = vec.sub([x1 + w1 / 2, y1 + h1], [x0 + w0 / 2, y0 + h0])
}
} else if (x0 !== x1) {
if (y0 !== y1) {
// moving top left, pin bottom right
delta = vec.sub([x1, y1], [x0, y0])
} else {
// moving bottom left, pin top right
delta = vec.sub([x1, y1 + h1], [x0, y0 + h0])
}
} else if (y0 !== y1) {
// moving top right, pin bottom left
delta = vec.sub([x1 + w1, y1], [x0 + w0, y0])
} else {
// moving bottom right, pin top left
delta = vec.sub([x1 + w1, y1 + h1], [x0 + w0, y0 + h0])
}
return delta
}
function renderPath(shape: ArrowShape, endAngle = 0) {
const { style, id } = shape
const { start, end } = shape.handles
const getRandom = rng(id)
const strokeWidth = +getShapeStyle(style).strokeWidth * 2
const arrowDist = vec.dist(start.point, end.point)
const styles = getShapeStyle(shape.style)
const sw = +styles.strokeWidth
const length = Math.min(arrowDist / 2, 24 + sw * 2)
const u = vec.uni(vec.vec(start.point, end.point))
const v = vec.rot(vec.mul(vec.neg(u), length), endAngle)
// Start
const a = start.point
// Middle
const m = vec.add(
vec.lrp(start.point, end.point, 0.25 + Math.abs(getRandom()) / 2),
[getRandom() * sw, getRandom() * sw]
)
// End
const b = end.point
// Left
let c = vec.add(
end.point,
vec.rot(v, Math.PI / 6 + (Math.PI / 8) * getRandom())
)
// Right
let d = vec.add(
end.point,
vec.rot(v, -(Math.PI / 6) + (Math.PI / 8) * getRandom())
)
if (getRandom() > 0.5) {
;[c, d] = [d, c]
}
const points = endAngle
? [
// Just the arrowhead
...pointsBetween(b, c),
...pointsBetween(c, b),
...pointsBetween(b, d),
...pointsBetween(d, b),
]
: [
// The shaft too
b,
a,
...pointsBetween(a, m),
...pointsBetween(m, b),
...pointsBetween(b, c),
...pointsBetween(c, b),
...pointsBetween(b, d),
...pointsBetween(d, b),
]
const stroke = getStroke(points, {
size: 1 + strokeWidth,
thinning: 0.6,
easing: (t) => t * t * t * t,
end: { taper: strokeWidth * 20 },
start: { taper: strokeWidth * 20 },
simulatePressure: false,
})
pathCache.set(shape, getSvgPathFromStroke(stroke))
}