tldraw/state/sessions/draw-session.ts
2021-06-02 16:05:44 +01:00

128 lines
3.2 KiB
TypeScript

import { current } from 'immer'
import { Data, DrawShape } from 'types'
import BaseSession from './base-session'
import { getShapeUtils } from 'lib/shape-utils'
import { getPage } from 'utils/utils'
import * as vec from 'utils/vec'
import commands from 'state/commands'
let prevEndPoint: number[]
export default class BrushSession extends BaseSession {
origin: number[]
previous: number[]
points: number[][]
snapshot: DrawSnapshot
isLocked: boolean
lockedDirection: 'horizontal' | 'vertical'
constructor(data: Data, id: string, point: number[], isLocked = false) {
super(data)
this.origin = point
this.previous = point
this.points = []
this.snapshot = getDrawSnapshot(data, id)
const page = getPage(data)
const shape = page.shapes[id]
getShapeUtils(shape).setProperty(shape, 'point', point)
}
update = (data: Data, point: number[], isLocked = false) => {
const { snapshot } = this
const delta = vec.vec(this.origin, point)
if (isLocked) {
if (!this.isLocked && this.points.length > 1) {
this.isLocked = true
const returning = [...this.previous]
if (Math.abs(delta[0]) < Math.abs(delta[1])) {
this.lockedDirection = 'vertical'
returning[0] = this.origin[0]
} else {
this.lockedDirection = 'horizontal'
returning[1] = this.origin[1]
}
this.previous = returning
this.points.push(vec.sub(returning, this.origin))
}
} else {
if (this.isLocked) {
this.isLocked = false
}
}
if (this.isLocked) {
if (this.lockedDirection === 'vertical') {
point[0] = this.origin[0]
} else {
point[1] = this.origin[1]
}
}
if (this.previous) {
point = vec.med(this.previous, point)
}
prevEndPoint = [...point]
const next = vec.sub(point, this.origin)
this.points.push(next)
this.previous = point
const page = getPage(data)
const shape = page.shapes[snapshot.id] as DrawShape
getShapeUtils(shape).setProperty(shape, 'points', [...this.points])
}
cancel = (data: Data) => {
const { snapshot } = this
const page = getPage(data)
const shape = page.shapes[snapshot.id] as DrawShape
getShapeUtils(shape).setProperty(shape, 'points', snapshot.points)
}
complete = (data: Data) => {
if (this.points.length > 1) {
let minX = Infinity
let minY = Infinity
const pts = [...this.points]
for (let pt of pts) {
minX = Math.min(pt[0], minX)
minY = Math.min(pt[1], minY)
}
for (let pt of pts) {
pt[0] -= minX
pt[1] -= minY
}
const { snapshot } = this
const page = getPage(data)
const shape = page.shapes[snapshot.id] as DrawShape
getShapeUtils(shape)
.setProperty(shape, 'points', pts)
.setProperty(shape, 'point', vec.add(shape.point, [minX, minY]))
}
commands.draw(data, this.snapshot.id, this.points)
}
}
export function getDrawSnapshot(data: Data, shapeId: string) {
const page = getPage(current(data))
const { points } = page.shapes[shapeId] as DrawShape
return {
id: shapeId,
points,
}
}
export type DrawSnapshot = ReturnType<typeof getDrawSnapshot>