From 65b24861bc2e5f25b08373b2c5afdf15d3256e90 Mon Sep 17 00:00:00 2001
From: Brandon Aaron <brandon.aaron@gmail.com>
Date: Thu, 2 Sep 2010 21:06:40 -0500
Subject: [PATCH] First look at css hooks. These hooks provide a way to change
 how jQuery handles getting and setting certain css properties. This means
 normalizing properties like background-position can easily be done via
 plugins.

They are similar in concept to the special event hooks. Return false from the hook to revert control back to jQuery's normal processes for getting and setting certain css properties.
---
 src/css.js | 86 ++++++++++++++++++++++++++++++++++--------------------
 1 file changed, 54 insertions(+), 32 deletions(-)

diff --git a/src/css.js b/src/css.js
index cb65c0ba3..497303a81 100644
--- a/src/css.js
+++ b/src/css.js
@@ -25,7 +25,7 @@ jQuery.fn.css = function( name, value ) {
 		if ( value === undefined ) {
 			return jQuery.curCSS( elem, name );
 		}
-		
+
 		if ( typeof value === "number" && !rexclude.test(name) ) {
 			value += "px";
 		}
@@ -35,22 +35,30 @@ jQuery.fn.css = function( name, value ) {
 };
 
 jQuery.extend({
-	style: function( elem, name, value ) {
-		// don't set styles on text and comment nodes
-		if ( !elem || elem.nodeType === 3 || elem.nodeType === 8 ) {
-			return undefined;
-		}
-
-		// ignore negative width and height values #1599
-		if ( (name === "width" || name === "height") && parseFloat(value) < 0 ) {
-			value = undefined;
-		}
+	cssHooks: {
+		opacity: {
+			get: function( elem, force ) {
+				var style = elem.style;
+				if ( jQuery.support.opacity && !style.filter ) {
+					return false; // move along, nothing to see here
+				}
+
+				// IE uses filters for opacity
+				var ret = ropacity.test(elem.currentStyle.filter || "") ?
+							(parseFloat(RegExp.$1) / 100) + "" :
+							"";
+
+				return ret === "" ?
+					"1" :
+					ret;
+			},
+
+			set: function( elem, value ) {
+				var style = elem.style;
+				if ( jQuery.support.opacity && !style.filter ) {
+					return false; // move along, nothing to see here
+				}
 
-		var style = elem.style || elem, set = value !== undefined;
-
-		// IE uses filters for opacity
-		if ( !jQuery.support.opacity && name === "opacity" && style.filter ) {
-			if ( set ) {
 				// IE has trouble with opacity if it does not have layout
 				// Force it by setting the zoom level
 				style.zoom = 1;
@@ -60,12 +68,22 @@ jQuery.extend({
 				var filter = style.filter || jQuery.curCSS( elem, "filter" ) || "";
 				style.filter = ralpha.test(filter) ? filter.replace(ralpha, opacity) : opacity;
 			}
+		}
+	},
+
+	style: function( elem, name, value ) {
+		// don't set styles on text and comment nodes
+		if ( !elem || elem.nodeType === 3 || elem.nodeType === 8 ) {
+			return undefined;
+		}
 
-			return style.filter && style.filter.indexOf("opacity=") >= 0 ?
-				(parseFloat( ropacity.exec(style.filter)[1] ) / 100) + "":
-				"";
+		// ignore negative width and height values #1599
+		if ( (name === "width" || name === "height") && parseFloat(value) < 0 ) {
+			value = undefined;
 		}
 
+		var style = elem.style || elem, set = value !== undefined;
+
 		// Make sure we're using the right name for getting the float value
 		if ( rfloat.test( name ) ) {
 			name = styleFloat;
@@ -73,8 +91,19 @@ jQuery.extend({
 
 		name = name.replace(rdashAlpha, fcamelCase);
 
+		var hooks = jQuery.cssHooks[name] || {};
+
 		if ( set ) {
-			style[ name ] = value;
+			if ( !('set' in hooks) || hooks.set( elem, value ) === false ) {
+				style[ name ] = value;
+			}
+		}
+
+		if ( 'get' in hooks ) {
+			var cssHookReturn = hooks.get( elem, false );
+			if ( cssHookReturn !== false ) {
+				return cssHookReturn;
+			}
 		}
 
 		return style[ name ];
@@ -98,24 +127,17 @@ jQuery.extend({
 	},
 
 	curCSS: function( elem, name, force ) {
-		var ret, style = elem.style, filter;
-
-		// IE uses filters for opacity
-		if ( !jQuery.support.opacity && name === "opacity" && elem.currentStyle ) {
-			ret = ropacity.test(elem.currentStyle.filter || "") ?
-				(parseFloat(RegExp.$1) / 100) + "" :
-				"";
-
-			return ret === "" ?
-				"1" :
-				ret;
-		}
+		var ret, style = elem.style, filter, hooks = jQuery.cssHooks[name] || {};
 
 		// Make sure we're using the right name for getting the float value
 		if ( rfloat.test( name ) ) {
 			name = styleFloat;
 		}
 
+		if ( 'get' in hooks && ( ret = hooks.get( elem, force ) ) !== false ) {
+			return ret;
+		}
+
 		if ( !force && style && style[ name ] ) {
 			ret = style[ name ];
 
-- 
2.39.5