Skip to content

Keep the knob from jumping between min and max mid-drag #792

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

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

Keep the knob from jumping between min and max mid-drag #792

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
20 changes: 18 additions & 2 deletions www/js/jquery.knob.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -62,6 +62,7 @@
this.$c = null; // jQuery canvas element
this.c = null; // rendered canvas context
this.t = 0; // touches index
this.ga = null; // gesture angle ; tracks the arc during a drag
this.isInit = false;
this.fgColor = null; // main color
this.pColor = null; // previous color
Expand Down Expand Up @@ -323,7 +324,8 @@
// get touches index
this.t = k.c.t(e);

// First touch
// First touch is absolute
s.ga = null;
touchMove(e);

// Touch events listeners
Expand Down Expand Up @@ -370,7 +372,8 @@
s._draw();
};

// First click
// First click is absolute
s.ga = null;
mouseMove(e);

// Mouse events listeners
Expand Down Expand Up @@ -567,6 +570,19 @@
a += this.PI2;
}

// Follow the arc during a drag instead of jumping across the seam
// where min and max meet
if (this.ga !== null) {
var d = a - this.ga;
if (d > Math.PI) {
d -= this.PI2;
} else if (d < -Math.PI) {
d += this.PI2;
}
a = max(0, min(this.angleArc, this.ga + d));
}
this.ga = a;

ret = ~~ (0.5 + (a * (this.o.max - this.o.min) / this.angleArc))
+ this.o.min;

Expand Down