1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/dom/smil/nsSMILCompositor.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,186 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#include "nsSMILCompositor.h"
1.10 +#include "nsSMILCSSProperty.h"
1.11 +#include "nsCSSProps.h"
1.12 +#include "nsHashKeys.h"
1.13 +
1.14 +// PLDHashEntryHdr methods
1.15 +bool
1.16 +nsSMILCompositor::KeyEquals(KeyTypePointer aKey) const
1.17 +{
1.18 + return aKey && aKey->Equals(mKey);
1.19 +}
1.20 +
1.21 +/*static*/ PLDHashNumber
1.22 +nsSMILCompositor::HashKey(KeyTypePointer aKey)
1.23 +{
1.24 + // Combine the 3 values into one numeric value, which will be hashed.
1.25 + // NOTE: We right-shift one of the pointers by 2 to get some randomness in
1.26 + // its 2 lowest-order bits. (Those shifted-off bits will always be 0 since
1.27 + // our pointers will be word-aligned.)
1.28 + return (NS_PTR_TO_UINT32(aKey->mElement.get()) >> 2) +
1.29 + NS_PTR_TO_UINT32(aKey->mAttributeName.get()) +
1.30 + (aKey->mIsCSS ? 1 : 0);
1.31 +}
1.32 +
1.33 +// Cycle-collection support
1.34 +void
1.35 +nsSMILCompositor::Traverse(nsCycleCollectionTraversalCallback* aCallback)
1.36 +{
1.37 + if (!mKey.mElement)
1.38 + return;
1.39 +
1.40 + NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(*aCallback, "Compositor mKey.mElement");
1.41 + aCallback->NoteXPCOMChild(mKey.mElement);
1.42 +}
1.43 +
1.44 +// Other methods
1.45 +void
1.46 +nsSMILCompositor::AddAnimationFunction(nsSMILAnimationFunction* aFunc)
1.47 +{
1.48 + if (aFunc) {
1.49 + mAnimationFunctions.AppendElement(aFunc);
1.50 + }
1.51 +}
1.52 +
1.53 +void
1.54 +nsSMILCompositor::ComposeAttribute()
1.55 +{
1.56 + if (!mKey.mElement)
1.57 + return;
1.58 +
1.59 + // FIRST: Get the nsISMILAttr (to grab base value from, and to eventually
1.60 + // give animated value to)
1.61 + nsAutoPtr<nsISMILAttr> smilAttr(CreateSMILAttr());
1.62 + if (!smilAttr) {
1.63 + // Target attribute not found (or, out of memory)
1.64 + return;
1.65 + }
1.66 + if (mAnimationFunctions.IsEmpty()) {
1.67 + // No active animation functions. (We can still have a nsSMILCompositor in
1.68 + // that case if an animation function has *just* become inactive)
1.69 + smilAttr->ClearAnimValue();
1.70 + return;
1.71 + }
1.72 +
1.73 + // SECOND: Sort the animationFunctions, to prepare for compositing.
1.74 + nsSMILAnimationFunction::Comparator comparator;
1.75 + mAnimationFunctions.Sort(comparator);
1.76 +
1.77 + // THIRD: Step backwards through animation functions to find out
1.78 + // which ones we actually care about.
1.79 + uint32_t firstFuncToCompose = GetFirstFuncToAffectSandwich();
1.80 +
1.81 + // FOURTH: Get & cache base value
1.82 + nsSMILValue sandwichResultValue;
1.83 + if (!mAnimationFunctions[firstFuncToCompose]->WillReplace()) {
1.84 + sandwichResultValue = smilAttr->GetBaseValue();
1.85 + }
1.86 + UpdateCachedBaseValue(sandwichResultValue);
1.87 +
1.88 + if (!mForceCompositing) {
1.89 + return;
1.90 + }
1.91 +
1.92 + // FIFTH: Compose animation functions
1.93 + uint32_t length = mAnimationFunctions.Length();
1.94 + for (uint32_t i = firstFuncToCompose; i < length; ++i) {
1.95 + mAnimationFunctions[i]->ComposeResult(*smilAttr, sandwichResultValue);
1.96 + }
1.97 + if (sandwichResultValue.IsNull()) {
1.98 + smilAttr->ClearAnimValue();
1.99 + return;
1.100 + }
1.101 +
1.102 + // SIXTH: Set the animated value to the final composited result.
1.103 + nsresult rv = smilAttr->SetAnimValue(sandwichResultValue);
1.104 + if (NS_FAILED(rv)) {
1.105 + NS_WARNING("nsISMILAttr::SetAnimValue failed");
1.106 + }
1.107 +}
1.108 +
1.109 +void
1.110 +nsSMILCompositor::ClearAnimationEffects()
1.111 +{
1.112 + if (!mKey.mElement || !mKey.mAttributeName)
1.113 + return;
1.114 +
1.115 + nsAutoPtr<nsISMILAttr> smilAttr(CreateSMILAttr());
1.116 + if (!smilAttr) {
1.117 + // Target attribute not found (or, out of memory)
1.118 + return;
1.119 + }
1.120 + smilAttr->ClearAnimValue();
1.121 +}
1.122 +
1.123 +// Protected Helper Functions
1.124 +// --------------------------
1.125 +nsISMILAttr*
1.126 +nsSMILCompositor::CreateSMILAttr()
1.127 +{
1.128 + if (mKey.mIsCSS) {
1.129 + nsCSSProperty propId =
1.130 + nsCSSProps::LookupProperty(nsDependentAtomString(mKey.mAttributeName),
1.131 + nsCSSProps::eEnabledForAllContent);
1.132 + if (nsSMILCSSProperty::IsPropertyAnimatable(propId)) {
1.133 + return new nsSMILCSSProperty(propId, mKey.mElement.get());
1.134 + }
1.135 + } else {
1.136 + return mKey.mElement->GetAnimatedAttr(mKey.mAttributeNamespaceID,
1.137 + mKey.mAttributeName);
1.138 + }
1.139 + return nullptr;
1.140 +}
1.141 +
1.142 +uint32_t
1.143 +nsSMILCompositor::GetFirstFuncToAffectSandwich()
1.144 +{
1.145 + uint32_t i;
1.146 + for (i = mAnimationFunctions.Length(); i > 0; --i) {
1.147 + nsSMILAnimationFunction* curAnimFunc = mAnimationFunctions[i-1];
1.148 + // In the following, the lack of short-circuit behavior of |= means that we
1.149 + // will ALWAYS run UpdateCachedTarget (even if mForceCompositing is true)
1.150 + // but only call HasChanged and WasSkippedInPrevSample if necessary. This
1.151 + // is important since we need UpdateCachedTarget to run in order to detect
1.152 + // changes to the target in subsequent samples.
1.153 + mForceCompositing |=
1.154 + curAnimFunc->UpdateCachedTarget(mKey) ||
1.155 + curAnimFunc->HasChanged() ||
1.156 + curAnimFunc->WasSkippedInPrevSample();
1.157 +
1.158 + if (curAnimFunc->WillReplace()) {
1.159 + --i;
1.160 + break;
1.161 + }
1.162 + }
1.163 + // Mark remaining animation functions as having been skipped so if we later
1.164 + // use them we'll know to force compositing.
1.165 + // Note that we only really need to do this if something has changed
1.166 + // (otherwise we would have set the flag on a previous sample) and if
1.167 + // something has changed mForceCompositing will be true.
1.168 + if (mForceCompositing) {
1.169 + for (uint32_t j = i; j > 0; --j) {
1.170 + mAnimationFunctions[j-1]->SetWasSkipped();
1.171 + }
1.172 + }
1.173 + return i;
1.174 +}
1.175 +
1.176 +void
1.177 +nsSMILCompositor::UpdateCachedBaseValue(const nsSMILValue& aBaseValue)
1.178 +{
1.179 + if (!mCachedBaseValue) {
1.180 + // We don't have last sample's base value cached. Assume it's changed.
1.181 + mCachedBaseValue = new nsSMILValue(aBaseValue);
1.182 + NS_WARN_IF_FALSE(mCachedBaseValue, "failed to cache base value (OOM?)");
1.183 + mForceCompositing = true;
1.184 + } else if (*mCachedBaseValue != aBaseValue) {
1.185 + // Base value has changed since last sample.
1.186 + *mCachedBaseValue = aBaseValue;
1.187 + mForceCompositing = true;
1.188 + }
1.189 +}
