diff options
Diffstat (limited to 'library/tk.tcl')
| -rw-r--r-- | library/tk.tcl | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/library/tk.tcl b/library/tk.tcl index 0bb49eb..1345fbf 100644 --- a/library/tk.tcl +++ b/library/tk.tcl @@ -844,6 +844,19 @@ if {[tk windowingsystem] eq "x11"} { if {$::ttk::library ne ""} { uplevel \#0 [list source -encoding utf-8 $::ttk::library/ttk.tcl] } + +# Helper for smooth scrolling of Canvas widgets +proc ::tk::CanvasScrollByPixels {canvas deltaX deltaY} { + set width [expr {1.0 * [$canvas cget -width]}] + set height [expr {1.0 * [$canvas cget -height]}] + set X [lindex [$canvas xview] 0] + set Y [lindex [$canvas yview] 0] + set x [expr {$X - $deltaX / $width}] + set y [expr {$Y - $deltaY / $height}] + $canvas xview moveto $x + $canvas yview moveto $y +} + # Local Variables: # mode: tcl |