tldraw/state/shape-utils/arrow.tsx
2021-06-23 19:00:06 +01:00

554 lines
14 KiB
TypeScript

import { getArcLength, uniqueId } from 'utils/utils'
import vec from 'utils/vec'
import {
getSvgPathFromStroke,
rng,
getBoundsFromPoints,
translateBounds,
pointsBetween,
} from 'utils/utils'
import {
ArrowShape,
DashStyle,
Decoration,
ShapeHandle,
ShapeType,
} from 'types'
import { circleFromThreePoints, isAngleBetween } from 'utils/utils'
import { pointInBounds } from 'utils/hitTests'
import {
intersectArcBounds,
intersectLineSegmentBounds,
} from 'utils/intersections'
import { pointInCircle } from 'utils/hitTests'
import { defaultStyle, getShapeStyle } from 'state/shape-styles'
import getStroke from 'perfect-freehand'
import React from 'react'
import { registerShapeUtils } from './register'
import { getPerfectDashProps } from 'utils/dashes'
const pathCache = new WeakMap<ArrowShape, string>([])
// A cache for semi-expensive circles calculated from three points
function getCtp(shape: ArrowShape) {
const { start, end, bend } = shape.handles
return circleFromThreePoints(start.point, end.point, bend.point)
}
const arrow = registerShapeUtils<ArrowShape>({
boundsCache: new WeakMap([]),
create(props) {
const {
point = [0, 0],
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,
handles,
decorations: {
start: null,
middle: null,
end: Decoration.Arrow,
},
...props,
style: {
...defaultStyle,
...props.style,
isFilled: false,
},
}
},
render(shape) {
const { id, bend, handles, style } = shape
const { start, end, bend: _bend } = handles
const isStraightLine = vec.isEqual(
_bend.point,
vec.med(start.point, end.point)
)
const styles = getShapeStyle(style)
const strokeWidth = +styles.strokeWidth
const sw =
strokeWidth * (style.dash === DashStyle.Solid && bend === 0 ? 1 : 1.618)
const arrowDist = vec.dist(start.point, end.point)
let shaftPath: JSX.Element
let startAngle: number
let endAngle: number
if (isStraightLine) {
if (shape.style.dash === DashStyle.Solid && !pathCache.has(shape)) {
renderFreehandArrowShaft(shape)
}
const path =
shape.style.dash === DashStyle.Solid
? pathCache.get(shape)
: 'M' + start.point + 'L' + end.point
const { strokeDasharray, strokeDashoffset } =
shape.style.dash === DashStyle.Solid
? {
strokeDasharray: 'none',
strokeDashoffset: '0',
}
: getPerfectDashProps(
arrowDist,
sw,
shape.style.dash === DashStyle.Dotted ? 'dotted' : 'dashed',
2
)
startAngle = Math.PI
endAngle = 0
shaftPath = (
<>
<path
d={path}
stroke="transparent"
fill="none"
strokeWidth={Math.max(8, strokeWidth * 2)}
strokeDasharray="none"
strokeDashoffset="none"
strokeLinecap="round"
/>
<path
d={path}
fill="none"
strokeWidth={sw}
strokeDasharray={strokeDasharray}
strokeDashoffset={strokeDashoffset}
strokeLinecap="round"
></path>
</>
)
} else {
const circle = getCtp(shape)
const path = getArrowArcPath(start, end, circle, bend)
const { strokeDasharray, strokeDashoffset } =
shape.style.dash === DashStyle.Solid
? {
strokeDasharray: 'none',
strokeDashoffset: '0',
}
: getPerfectDashProps(
getArcLength(
[circle[0], circle[1]],
circle[2],
start.point,
end.point
) - 1,
sw,
shape.style.dash === DashStyle.Dotted ? 'dotted' : 'dashed',
2
)
startAngle =
vec.angle([circle[0], circle[1]], start.point) -
vec.angle(end.point, start.point) +
(Math.PI / 2) * (bend > 0 ? 0.98 : -0.98)
endAngle =
vec.angle([circle[0], circle[1]], end.point) -
vec.angle(start.point, end.point) +
(Math.PI / 2) * (bend > 0 ? 0.98 : -0.98)
shaftPath = (
<>
<path
d={path}
stroke="transparent"
fill="none"
strokeWidth={Math.max(8, strokeWidth * 2)}
strokeDasharray="none"
strokeDashoffset="none"
strokeLinecap="round"
/>
<path
d={path}
fill="none"
strokeWidth={sw}
strokeDasharray={strokeDasharray}
strokeDashoffset={strokeDashoffset}
strokeLinecap="round"
></path>
</>
)
}
return (
<g id={id}>
{shaftPath}
{shape.decorations.start === Decoration.Arrow && (
<path
d={getArrowHeadPath(shape, start.point, startAngle)}
strokeWidth={strokeWidth * 1.618}
fill="none"
strokeDashoffset="none"
strokeDasharray="none"
/>
)}
{shape.decorations.end === Decoration.Arrow && (
<path
d={getArrowHeadPath(shape, end.point, endAngle)}
strokeWidth={strokeWidth * 1.618}
fill="none"
strokeDashoffset="none"
strokeDasharray="none"
/>
)}
</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, bend, end } = shape.handles
this.boundsCache.set(
shape,
getBoundsFromPoints([start.point, bend.point, end.point])
)
}
return translateBounds(this.boundsCache.get(shape), shape.point)
},
getRotatedBounds(shape) {
const { start, bend, end } = shape.handles
return translateBounds(
getBoundsFromPoints([start.point, bend.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 } = 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)
// let nw = initialShape.point[0] / initialShapeBounds.width
// let nh = initialShape.point[1] / initialShapeBounds.height
// shape.point = [
// bounds.width * (scaleX < 0 ? 1 - nw : nw),
// bounds.height * (scaleY < 0 ? 1 - nh : nh),
// ]
shape.point = [bounds.minX, bounds.minY]
const handles = ['start', 'end']
handles.forEach((handle) => {
const [x, y] = initialShape.handles[handle].point
const nw = x / initialShapeBounds.width
const nh = y / initialShapeBounds.height
shape.handles[handle].point = [
bounds.width * (scaleX < 0 ? 1 - nw : nw),
bounds.height * (scaleY < 0 ? 1 - nh : nh),
]
})
const { start, bend, end } = shape.handles
const dist = vec.dist(start.point, end.point)
const midPoint = vec.med(start.point, end.point)
const bendDist = (dist / 2) * initialShape.bend
const u = vec.uni(vec.vec(start.point, end.point))
const point = vec.add(midPoint, vec.mul(vec.per(u), bendDist))
bend.point = Math.abs(bendDist) < 10 ? midPoint : point
return this
},
onDoublePointHandle(shape, handle) {
switch (handle) {
case 'bend': {
shape.bend = 0
shape.handles.bend.point = getBendPoint(shape)
break
}
case 'start': {
shape.decorations.start = shape.decorations.start
? null
: Decoration.Arrow
break
}
case 'end': {
shape.decorations.end = shape.decorations.end ? null : Decoration.Arrow
break
}
}
return this
},
onHandleChange(shape, handles) {
for (const id in handles) {
const handle = handles[id]
shape.handles[handle.id] = handle
}
if ('bend' in handles) {
const { start, end, bend } = shape.handles
const dist = vec.dist(start.point, end.point)
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)
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)
shape.handles = { ...shape.handles }
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 renderFreehandArrowShaft(shape: ArrowShape) {
const { style, id } = shape
const { start, end } = shape.handles
const getRandom = rng(id)
const strokeWidth = +getShapeStyle(style).strokeWidth * 2
const m = vec.add(
vec.lrp(start.point, end.point, 0.25 + Math.abs(getRandom()) / 2),
[getRandom() * strokeWidth, getRandom() * strokeWidth]
)
const stroke = getStroke(
[
...pointsBetween(start.point, m),
...pointsBetween(m, end.point),
end.point,
end.point,
end.point,
],
{
size: 1 + strokeWidth,
thinning: 0.6,
easing: (t) => t * t * t * t,
end: { taper: strokeWidth * 2 },
start: { taper: strokeWidth * 2 },
simulatePressure: false,
}
)
pathCache.set(shape, getSvgPathFromStroke(stroke))
}
function getArrowHeadPath(shape: ArrowShape, point: number[], angle = 0) {
const { left, right } = getArrowHeadPoints(shape, point, angle)
return ['M', left, 'L', point, right].join(' ')
}
function getArrowHeadPoints(shape: ArrowShape, point: number[], angle = 0) {
const { start, end } = shape.handles
const stroke = +getShapeStyle(shape.style).strokeWidth * 2
const arrowDist = vec.dist(start.point, end.point)
const arrowHeadlength = Math.min(arrowDist / 3, stroke * 4)
// Unit vector from start to end
const u = vec.uni(vec.vec(start.point, end.point))
// The end of the arrowhead wings
const v = vec.rot(vec.mul(vec.neg(u), arrowHeadlength), angle)
// Use the shape's random seed to create minor offsets for the angles
const getRandom = rng(shape.id)
return {
left: vec.add(point, vec.rot(v, Math.PI / 6 + (Math.PI / 8) * getRandom())),
right: vec.add(
point,
vec.rot(v, -(Math.PI / 6) + (Math.PI / 8) * getRandom())
),
}
}