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2 kBJavaScriptView Raw
1define( [
2 "../core",
3 "../var/rcssNum"
4], function( jQuery, rcssNum ) {
5
6"use strict";
7
8function adjustCSS( elem, prop, valueParts, tween ) {
9 var adjusted, scale,
10 maxIterations = 20,
11 currentValue = tween ?
12 function() {
13 return tween.cur();
14 } :
15 function() {
16 return jQuery.css( elem, prop, "" );
17 },
18 initial = currentValue(),
19 unit = valueParts && valueParts[ 3 ] || ( jQuery.cssNumber[ prop ] ? "" : "px" ),
20
21 // Starting value computation is required for potential unit mismatches
22 initialInUnit = elem.nodeType &&
23 ( jQuery.cssNumber[ prop ] || unit !== "px" && +initial ) &&
24 rcssNum.exec( jQuery.css( elem, prop ) );
25
26 if ( initialInUnit && initialInUnit[ 3 ] !== unit ) {
27
28 // Support: Firefox <=54
29 // Halve the iteration target value to prevent interference from CSS upper bounds (gh-2144)
30 initial = initial / 2;
31
32 // Trust units reported by jQuery.css
33 unit = unit || initialInUnit[ 3 ];
34
35 // Iteratively approximate from a nonzero starting point
36 initialInUnit = +initial || 1;
37
38 while ( maxIterations-- ) {
39
40 // Evaluate and update our best guess (doubling guesses that zero out).
41 // Finish if the scale equals or crosses 1 (making the old*new product non-positive).
42 jQuery.style( elem, prop, initialInUnit + unit );
43 if ( ( 1 - scale ) * ( 1 - ( scale = currentValue() / initial || 0.5 ) ) <= 0 ) {
44 maxIterations = 0;
45 }
46 initialInUnit = initialInUnit / scale;
47
48 }
49
50 initialInUnit = initialInUnit * 2;
51 jQuery.style( elem, prop, initialInUnit + unit );
52
53 // Make sure we update the tween properties later on
54 valueParts = valueParts || [];
55 }
56
57 if ( valueParts ) {
58 initialInUnit = +initialInUnit || +initial || 0;
59
60 // Apply relative offset (+=/-=) if specified
61 adjusted = valueParts[ 1 ] ?
62 initialInUnit + ( valueParts[ 1 ] + 1 ) * valueParts[ 2 ] :
63 +valueParts[ 2 ];
64 if ( tween ) {
65 tween.unit = unit;
66 tween.start = initialInUnit;
67 tween.end = adjusted;
68 }
69 }
70 return adjusted;
71}
72
73return adjustCSS;
74} );