gecko-dev/layout/style/AnimationCommon.cpp

/* vim: set shiftwidth=2 tabstop=8 autoindent cindent expandtab: */
/* ***** 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 AnimationCommon, common animation code for transitions
 * and animations.
 *
 * The Initial Developer of the Original Code is the Mozilla Foundation.
 * Portions created by the Initial Developer are Copyright (C) 2011
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   L. David Baron <dbaron@dbaron.org>, Mozilla Corporation (original author)
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either 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 ***** */

#include "AnimationCommon.h"
#include "nsRuleData.h"
#include "nsCSSValue.h"
#include "nsStyleContext.h"

namespace mozilla {
namespace css {

CommonAnimationManager::CommonAnimationManager(nsPresContext *aPresContext)
  : mPresContext(aPresContext)
{
  PR_INIT_CLIST(&mElementData);
}

CommonAnimationManager::~CommonAnimationManager()
{
  NS_ABORT_IF_FALSE(!mPresContext, "Disconnect should have been called");
}

void
CommonAnimationManager::Disconnect()
{
  // Content nodes might outlive the transition or animation manager.
  RemoveAllElementData();

  mPresContext = nsnull;
}

void
CommonAnimationManager::AddElementData(CommonElementAnimationData* aData)
{
  if (PR_CLIST_IS_EMPTY(&mElementData)) {
    // We need to observe the refresh driver.
    nsRefreshDriver *rd = mPresContext->RefreshDriver();
    rd->AddRefreshObserver(this, Flush_Style);
  }

  PR_INSERT_BEFORE(aData, &mElementData);
}

void
CommonAnimationManager::ElementDataRemoved()
{
  // If we have no transitions or animations left, remove ourselves from
  // the refresh driver.
  if (PR_CLIST_IS_EMPTY(&mElementData)) {
    mPresContext->RefreshDriver()->RemoveRefreshObserver(this, Flush_Style);
  }
}

void
CommonAnimationManager::RemoveAllElementData()
{
  while (!PR_CLIST_IS_EMPTY(&mElementData)) {
    CommonElementAnimationData *head =
      static_cast<CommonElementAnimationData*>(PR_LIST_HEAD(&mElementData));
    head->Destroy();
  }
}

/*
 * nsISupports implementation
 */

NS_IMPL_ISUPPORTS1(CommonAnimationManager, nsIStyleRuleProcessor)

nsRestyleHint
CommonAnimationManager::HasStateDependentStyle(StateRuleProcessorData* aData)
{
  return nsRestyleHint(0);
}

PRBool
CommonAnimationManager::HasDocumentStateDependentStyle(StateRuleProcessorData* aData)
{
  return PR_FALSE;
}

nsRestyleHint
CommonAnimationManager::HasAttributeDependentStyle(AttributeRuleProcessorData* aData)
{
  return nsRestyleHint(0);
}

/* virtual */ PRBool
CommonAnimationManager::MediumFeaturesChanged(nsPresContext* aPresContext)
{
  return PR_FALSE;
}

/* static */ PRBool
CommonAnimationManager::ExtractComputedValueForTransition(
                          nsCSSProperty aProperty,
                          nsStyleContext* aStyleContext,
                          nsStyleAnimation::Value& aComputedValue)
{
  PRBool result =
    nsStyleAnimation::ExtractComputedValue(aProperty, aStyleContext,
                                           aComputedValue);
  if (aProperty == eCSSProperty_visibility) {
    NS_ABORT_IF_FALSE(aComputedValue.GetUnit() ==
                        nsStyleAnimation::eUnit_Enumerated,
                      "unexpected unit");
    aComputedValue.SetIntValue(aComputedValue.GetIntValue(),
                               nsStyleAnimation::eUnit_Visibility);
  }
  return result;
}

NS_IMPL_ISUPPORTS1(AnimValuesStyleRule, nsIStyleRule)

/* virtual */ void
AnimValuesStyleRule::MapRuleInfoInto(nsRuleData* aRuleData)
{
  nsStyleContext *contextParent = aRuleData->mStyleContext->GetParent();
  if (contextParent && contextParent->HasPseudoElementData()) {
    // Don't apply transitions or animations to things inside of
    // pseudo-elements.
    // FIXME (Bug 522599): Add tests for this.
    return;
  }

  for (PRUint32 i = 0, i_end = mPropertyValuePairs.Length(); i < i_end; ++i) {
    PropertyValuePair &cv = mPropertyValuePairs[i];
    if (aRuleData->mSIDs & nsCachedStyleData::GetBitForSID(
                             nsCSSProps::kSIDTable[cv.mProperty]))
    {
      nsCSSValue *prop = aRuleData->ValueFor(cv.mProperty);
      if (prop->GetUnit() == eCSSUnit_Null) {
#ifdef DEBUG
        PRBool ok =
#endif
          nsStyleAnimation::UncomputeValue(cv.mProperty,
                                           aRuleData->mPresContext,
                                           cv.mValue, *prop);
        NS_ABORT_IF_FALSE(ok, "could not store computed value");
      }
    }
  }
}

#ifdef DEBUG
/* virtual */ void
AnimValuesStyleRule::List(FILE* out, PRInt32 aIndent) const
{
  // WRITE ME?
}
#endif

void
ComputedTimingFunction::Init(const nsTimingFunction &aFunction)
{
  mType = aFunction.mType;
  if (mType == nsTimingFunction::Function) {
    mTimingFunction.Init(aFunction.mFunc.mX1, aFunction.mFunc.mY1,
                         aFunction.mFunc.mX2, aFunction.mFunc.mY2);
  } else {
    mSteps = aFunction.mSteps;
  }
}

static inline double
StepEnd(PRUint32 aSteps, double aPortion)
{
  NS_ABORT_IF_FALSE(0.0 <= aPortion && aPortion <= 1.0, "out of range");
  PRUint32 step = PRUint32(aPortion * aSteps); // floor
  return double(step) / double(aSteps);
}

double
ComputedTimingFunction::GetValue(double aPortion) const
{
  switch (mType) {
    case nsTimingFunction::Function:
      return mTimingFunction.GetSplineValue(aPortion);
    case nsTimingFunction::StepStart:
      // There are diagrams in the spec that seem to suggest this check
      // and the bounds point should not be symmetric with StepEnd, but
      // should actually step up at rather than immediately after the
      // fraction points.  However, we rely on rounding negative values
      // up to zero, so we can't do that.  And it's not clear the spec
      // really meant it.
      return 1.0 - StepEnd(mSteps, 1.0 - aPortion);
    default:
      NS_ABORT_IF_FALSE(PR_FALSE, "bad type");
      // fall through
    case nsTimingFunction::StepEnd:
      return StepEnd(mSteps, aPortion);
  }
}

}
}