Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Min pan distance #452

Open
wants to merge 1 commit into
base: main
Choose a base branch
from
Open

Min pan distance #452

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
48 changes: 32 additions & 16 deletions src/panzoom.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -43,6 +43,7 @@ const defaultOptions: PanzoomOptions = {
e.stopPropagation()
},
maxScale: 4,
minDistance: 0,
minScale: 0.125,
overflow: 'hidden',
panOnlyWhenZoomed: false,
Expand Down Expand Up @@ -128,6 +129,7 @@ function Panzoom(
let x = 0
let y = 0
let scale = 1
let isWatching = false
let isPanning = false
zoom(options.startScale, { animate: false })
// Wait for scale to update
Expand Down Expand Up @@ -427,13 +429,11 @@ function Panzoom(
return
}
addPointer(pointers, event)
isPanning = true
isWatching = true
options.handleStartEvent(event)
origX = x
origY = y

trigger('panzoomstart', { x, y, scale, isSVG, originalEvent: event }, options)

// This works whether there are multiple
// pointers or not
const point = getMiddle(pointers)
Expand All @@ -445,7 +445,7 @@ function Panzoom(

function move(event: PointerEvent) {
if (
!isPanning ||
!isWatching ||
origX === undefined ||
origY === undefined ||
startClientX === undefined ||
Expand All @@ -455,22 +455,37 @@ function Panzoom(
}
addPointer(pointers, event)
const current = getMiddle(pointers)
let scaleDiff = 0
if (pointers.length > 1) {
// Use the distance between the first 2 pointers
// to determine the current scale
const diff = getDistance(pointers) - startDistance
const toScale = constrainScale((diff * options.step) / 80 + startScale).scale
zoomToPoint(toScale, current)
scaleDiff = getDistance(pointers) - startDistance
}

if (!isPanning) {
// have we moved far enough to trigger panning/zooming
const panDiff = Math.hypot(current.clientX - startClientX, current.clientY - startClientY)
if (Math.abs(scaleDiff) > options.minDistance || panDiff > options.minDistance) {
trigger('panzoomstart', { x: origX, y: origY, scale: startScale, isSVG, originalEvent: event }, options)
isPanning = true
}
}

pan(
origX + (current.clientX - startClientX) / scale,
origY + (current.clientY - startClientY) / scale,
{
animate: false
},
event
)
if (isPanning) {
if (pointers.length > 1) {
const toScale = constrainScale((scaleDiff * options.step) / 80 + startScale).scale
zoomToPoint(toScale, current)
}

pan(
origX + (current.clientX - startClientX) / scale,
origY + (current.clientY - startClientY) / scale,
{
animate: false
},
event
)
}
}

function handleUp(event: PointerEvent) {
Expand All @@ -483,9 +498,10 @@ function Panzoom(
// Can restart without having to reinitiate all of them
// Remove the pointer regardless of the isPanning state
removePointer(pointers, event)
if (!isPanning) {
if (!isWatching) {
return
}
isWatching = false
isPanning = false
origX = origY = startClientX = startClientY = undefined
}
Expand Down