gecko-dev/content/smil/nsSMILCSSProperty.cpp

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is the Mozilla SMIL module.
*
* The Initial Developer of the Original Code is the Mozilla Corporation.
* Portions created by the Initial Developer are Copyright (C) 2009
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Daniel Holbert <dholbert@mozilla.com>
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
/* representation of a SMIL-animatable CSS property on an element */
#include "nsSMILCSSProperty.h"
#include "nsSMILCSSValueType.h"
#include "nsSMILValue.h"
#include "nsCSSDeclaration.h"
#include "nsComputedDOMStyle.h"
#include "nsStyleAnimation.h"
#include "nsIContent.h"
#include "nsIDOMElement.h"
using namespace mozilla::dom;
// Helper function
static PRBool
GetCSSComputedValue(nsIContent* aElem,
nsCSSProperty aPropID,
nsAString& aResult)
{
NS_ABORT_IF_FALSE(!nsCSSProps::IsShorthand(aPropID),
"Can't look up computed value of shorthand property");
NS_ABORT_IF_FALSE(nsSMILCSSProperty::IsPropertyAnimatable(aPropID),
"Shouldn't get here for non-animatable properties");
nsIDocument* doc = aElem->GetCurrentDoc();
if (!doc) {
// This can happen if we process certain types of restyles mid-sample
// and remove anonymous animated content from the document as a result.
// See bug 534975.
return PR_FALSE;
}
nsIPresShell* shell = doc->GetShell();
if (!shell) {
NS_WARNING("Unable to look up computed style -- no pres shell");
return PR_FALSE;
}
nsRefPtr<nsComputedDOMStyle> computedStyle;
nsCOMPtr<nsIDOMElement> domElement(do_QueryInterface(aElem));
nsresult rv = NS_NewComputedDOMStyle(domElement, EmptyString(), shell,
getter_AddRefs(computedStyle));
if (NS_SUCCEEDED(rv)) {
computedStyle->GetPropertyValue(aPropID, aResult);
return PR_TRUE;
}
return PR_FALSE;
}
// Class Methods
nsSMILCSSProperty::nsSMILCSSProperty(nsCSSProperty aPropID,
Element* aElement)
: mPropID(aPropID), mElement(aElement)
{
NS_ABORT_IF_FALSE(IsPropertyAnimatable(mPropID),
"Creating a nsSMILCSSProperty for a property "
"that's not supported for animation");
}
nsSMILValue
nsSMILCSSProperty::GetBaseValue() const
{
// To benefit from Return Value Optimization and avoid copy constructor calls
// due to our use of return-by-value, we must return the exact same object
// from ALL return points. This function must only return THIS variable:
nsSMILValue baseValue;
// SPECIAL CASE: Shorthands
if (nsCSSProps::IsShorthand(mPropID)) {
// We can't look up the base (computed-style) value of shorthand
// properties, because they aren't guaranteed to have a consistent computed
// value. However, that's not a problem, because it turns out the caller
// isn't going to end up using the value we return anyway. Base values only
// get used when there's interpolation or addition, and the shorthand
// properties we know about don't support those operations. So, we can just
// return a dummy value (initialized with the right type, so as not to
// indicate failure).
nsSMILValue tmpVal(&nsSMILCSSValueType::sSingleton);
baseValue.Swap(tmpVal);
return baseValue;
}
// GENERAL CASE: Non-Shorthands
// (1) Put empty string in override style for property mPropID
// (saving old override style value, so we can set it again when we're done)
nsCOMPtr<nsIDOMCSSStyleDeclaration> overrideStyle;
mElement->GetSMILOverrideStyle(getter_AddRefs(overrideStyle));
nsCOMPtr<nsICSSDeclaration> overrideDecl = do_QueryInterface(overrideStyle);
nsAutoString cachedOverrideStyleVal;
if (overrideDecl) {
overrideDecl->GetPropertyValue(mPropID, cachedOverrideStyleVal);
// (Don't bother clearing override style if it's already empty)
if (!cachedOverrideStyleVal.IsEmpty()) {
overrideDecl->SetPropertyValue(mPropID, EmptyString());
}
}
// (2) Get Computed Style
nsAutoString computedStyleVal;
PRBool didGetComputedVal = GetCSSComputedValue(mElement, mPropID,
computedStyleVal);
// (3) Put cached override style back (if it's non-empty)
if (overrideDecl && !cachedOverrideStyleVal.IsEmpty()) {
overrideDecl->SetPropertyValue(mPropID, cachedOverrideStyleVal);
}
// (4) Populate our nsSMILValue from the computed style
if (didGetComputedVal) {
nsSMILCSSValueType::ValueFromString(mPropID, mElement,
computedStyleVal, baseValue);
}
return baseValue;
}
nsresult
nsSMILCSSProperty::ValueFromString(const nsAString& aStr,
const nsISMILAnimationElement* aSrcElement,
nsSMILValue& aValue,
PRBool& aPreventCachingOfSandwich) const
{
NS_ENSURE_TRUE(IsPropertyAnimatable(mPropID), NS_ERROR_FAILURE);
nsSMILCSSValueType::ValueFromString(mPropID, mElement, aStr, aValue);
if (aValue.IsNull()) {
return NS_ERROR_FAILURE;
}
// XXXdholbert: For simplicity, just assume that all CSS values have to
// reparsed every sample. This prevents us from doing the "nothing's changed
// so don't recompose" optimization (bug 533291) for CSS properties & mapped
// attributes. If it ends up being expensive to always recompose those, we
// can be a little smarter here. We really only need to set
// aPreventCachingOfSandwich to true for "inherit" & "currentColor" (whose
// values could change at any time), for length-valued types (particularly
// those with em/ex/percent units, since their conversion ratios can change
// at any time), and for any value for 'font-family'.
aPreventCachingOfSandwich = PR_TRUE;
return NS_OK;
}
nsresult
nsSMILCSSProperty::SetAnimValue(const nsSMILValue& aValue)
{
NS_ENSURE_TRUE(IsPropertyAnimatable(mPropID), NS_ERROR_FAILURE);
// Convert nsSMILValue to string
nsAutoString valStr;
if (!nsSMILCSSValueType::ValueToString(aValue, valStr)) {
NS_WARNING("Failed to convert nsSMILValue for CSS property into a string");
return NS_ERROR_FAILURE;
}
// Use string value to style the target element
nsCOMPtr<nsIDOMCSSStyleDeclaration> overrideStyle;
mElement->GetSMILOverrideStyle(getter_AddRefs(overrideStyle));
NS_ABORT_IF_FALSE(overrideStyle, "Need a non-null overrideStyle");
nsCOMPtr<nsICSSDeclaration> overrideDecl = do_QueryInterface(overrideStyle);
if (overrideDecl) {
overrideDecl->SetPropertyValue(mPropID, valStr);
}
return NS_OK;
}
void
nsSMILCSSProperty::ClearAnimValue()
{
// Put empty string in override style for our property
nsCOMPtr<nsIDOMCSSStyleDeclaration> overrideStyle;
mElement->GetSMILOverrideStyle(getter_AddRefs(overrideStyle));
nsCOMPtr<nsICSSDeclaration> overrideDecl = do_QueryInterface(overrideStyle);
if (overrideDecl) {
overrideDecl->SetPropertyValue(mPropID, EmptyString());
}
}
// Based on http://www.w3.org/TR/SVG/propidx.html
// static
PRBool
nsSMILCSSProperty::IsPropertyAnimatable(nsCSSProperty aPropID)
{
// NOTE: Right now, Gecko doesn't recognize the following properties from
// the SVG Property Index:
// alignment-baseline
// baseline-shift
// color-profile
// color-rendering
// glyph-orientation-horizontal
// glyph-orientation-vertical
// kerning
// writing-mode
switch (aPropID) {
case eCSSProperty_clip:
case eCSSProperty_clip_rule:
case eCSSProperty_clip_path:
case eCSSProperty_color:
case eCSSProperty_color_interpolation:
case eCSSProperty_color_interpolation_filters:
case eCSSProperty_cursor:
case eCSSProperty_display:
case eCSSProperty_dominant_baseline:
case eCSSProperty_fill:
case eCSSProperty_fill_opacity:
case eCSSProperty_fill_rule:
case eCSSProperty_filter:
case eCSSProperty_flood_color:
case eCSSProperty_flood_opacity:
case eCSSProperty_font:
case eCSSProperty_font_family:
case eCSSProperty_font_size:
case eCSSProperty_font_size_adjust:
case eCSSProperty_font_stretch:
case eCSSProperty_font_style:
case eCSSProperty_font_variant:
case eCSSProperty_font_weight:
case eCSSProperty_image_rendering:
case eCSSProperty_letter_spacing:
case eCSSProperty_lighting_color:
case eCSSProperty_marker:
case eCSSProperty_marker_end:
case eCSSProperty_marker_mid:
case eCSSProperty_marker_start:
case eCSSProperty_mask:
case eCSSProperty_opacity:
case eCSSProperty_overflow:
case eCSSProperty_pointer_events:
case eCSSProperty_shape_rendering:
case eCSSProperty_stop_color:
case eCSSProperty_stop_opacity:
case eCSSProperty_stroke:
case eCSSProperty_stroke_dasharray:
case eCSSProperty_stroke_dashoffset:
case eCSSProperty_stroke_linecap:
case eCSSProperty_stroke_linejoin:
case eCSSProperty_stroke_miterlimit:
case eCSSProperty_stroke_opacity:
case eCSSProperty_stroke_width:
case eCSSProperty_text_anchor:
case eCSSProperty_text_decoration:
case eCSSProperty_text_rendering:
case eCSSProperty_visibility:
case eCSSProperty_word_spacing:
return PR_TRUE;
// EXPLICITLY NON-ANIMATABLE PROPERTIES:
// (Some of these aren't supported at all in Gecko -- I've commented those
// ones out. If/when we add support for them, uncomment their line here)
// ----------------------------------------------------------------------
// case eCSSProperty_enable_background:
// case eCSSProperty_glyph_orientation_horizontal:
// case eCSSProperty_glyph_orientation_vertical:
// case eCSSProperty_writing_mode:
case eCSSProperty_direction:
case eCSSProperty_unicode_bidi:
return PR_FALSE;
default:
return PR_FALSE;
}
}