layout/svg/FilterInstance.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 // Main header first:
   8 #include "FilterInstance.h"
   9
  10 // MFBT headers next:
  11 #include "mozilla/UniquePtr.h"
  12
  13 // Keep others in (case-insensitive) order:
  14 #include "FilterSupport.h"
  15 #include "ImgDrawResult.h"
  16 #include "SVGContentUtils.h"
  17 #include "gfx2DGlue.h"
  18 #include "gfxContext.h"
  19 #include "gfxPlatform.h"
  20
  21 #include "gfxUtils.h"
  22 #include "mozilla/Unused.h"
  23 #include "mozilla/gfx/Filters.h"
  24 #include "mozilla/gfx/Helpers.h"
  25 #include "mozilla/gfx/Logging.h"
  26 #include "mozilla/gfx/PatternHelpers.h"
  27 #include "mozilla/ISVGDisplayableFrame.h"
  28 #include "mozilla/StaticPrefs_gfx.h"
  29 #include "mozilla/SVGFilterInstance.h"
  30 #include "mozilla/SVGUtils.h"
  31 #include "mozilla/dom/Document.h"
  32 #include "nsLayoutUtils.h"
  33 #include "CSSFilterInstance.h"
  34 #include "SVGIntegrationUtils.h"
  35
  36 using namespace mozilla::dom;
  37 using namespace mozilla::gfx;
  38 using namespace mozilla::image;
  39
  40 namespace mozilla {
  41
  42 FilterDescription FilterInstance::GetFilterDescription(
  43     nsIContent* aFilteredElement, Span<const StyleFilter> aFilterChain,
  44     bool aFilterInputIsTainted, const UserSpaceMetrics& aMetrics,
  45     const gfxRect& aBBox,
  46     nsTArray<RefPtr<SourceSurface>>& aOutAdditionalImages) {
  47   gfxMatrix identity;
  48   FilterInstance instance(nullptr, aFilteredElement, aMetrics, aFilterChain,
  49                           aFilterInputIsTainted, nullptr, identity, nullptr,
  50                           nullptr, nullptr, &aBBox);
  51   if (!instance.IsInitialized()) {
  52     return FilterDescription();
  53   }
  54   return instance.ExtractDescriptionAndAdditionalImages(aOutAdditionalImages);
  55 }
  56
  57 static UniquePtr<UserSpaceMetrics> UserSpaceMetricsForFrame(nsIFrame* aFrame) {
  58   if (auto* element = SVGElement::FromNodeOrNull(aFrame->GetContent())) {
  59     return MakeUnique<SVGElementMetrics>(element);
  60   }
  61   return MakeUnique<NonSVGFrameUserSpaceMetrics>(aFrame);
  62 }
  63
  64 void FilterInstance::PaintFilteredFrame(
  65     nsIFrame* aFilteredFrame, Span<const StyleFilter> aFilterChain,
  66     gfxContext* aCtx, const SVGFilterPaintCallback& aPaintCallback,
  67     const nsRegion* aDirtyArea, imgDrawingParams& aImgParams, float aOpacity) {
  68   UniquePtr<UserSpaceMetrics> metrics =
  69       UserSpaceMetricsForFrame(aFilteredFrame);
  70
  71   gfxContextMatrixAutoSaveRestore autoSR(aCtx);
  72   auto scaleFactors = aCtx->CurrentMatrixDouble().ScaleFactors();
  73   if (scaleFactors.xScale == 0 || scaleFactors.yScale == 0) {
  74     return;
  75   }
  76
  77   gfxMatrix scaleMatrix(scaleFactors.xScale, 0.0f, 0.0f, scaleFactors.yScale,
  78                         0.0f, 0.0f);
  79
  80   gfxMatrix reverseScaleMatrix = scaleMatrix;
  81   DebugOnly<bool> invertible = reverseScaleMatrix.Invert();
  82   MOZ_ASSERT(invertible);
  83
  84   gfxMatrix scaleMatrixInDevUnits =
  85       scaleMatrix * SVGUtils::GetCSSPxToDevPxMatrix(aFilteredFrame);
  86
  87   // Hardcode InputIsTainted to true because we don't want JS to be able to
  88   // read the rendered contents of aFilteredFrame.
  89   FilterInstance instance(aFilteredFrame, aFilteredFrame->GetContent(),
  90                           *metrics, aFilterChain, /* InputIsTainted */ true,
  91                           aPaintCallback, scaleMatrixInDevUnits, aDirtyArea,
  92                           nullptr, nullptr, nullptr);
  93   if (instance.IsInitialized()) {
  94     // Pull scale vector out of aCtx's transform, put all scale factors, which
  95     // includes css and css-to-dev-px scale, into scaleMatrixInDevUnits.
  96     aCtx->SetMatrixDouble(reverseScaleMatrix * aCtx->CurrentMatrixDouble());
  97
  98     instance.Render(aCtx, aImgParams, aOpacity);
  99   } else {
 100     // Render the unfiltered contents.
 101     aPaintCallback(*aCtx, aImgParams, nullptr, nullptr);
 102   }
 103 }
 104
 105 static mozilla::wr::ComponentTransferFuncType FuncTypeToWr(uint8_t aFuncType) {
 106   MOZ_ASSERT(aFuncType != SVG_FECOMPONENTTRANSFER_SAME_AS_R);
 107   switch (aFuncType) {
 108     case SVG_FECOMPONENTTRANSFER_TYPE_TABLE:
 109       return mozilla::wr::ComponentTransferFuncType::Table;
 110     case SVG_FECOMPONENTTRANSFER_TYPE_DISCRETE:
 111       return mozilla::wr::ComponentTransferFuncType::Discrete;
 112     case SVG_FECOMPONENTTRANSFER_TYPE_LINEAR:
 113       return mozilla::wr::ComponentTransferFuncType::Linear;
 114     case SVG_FECOMPONENTTRANSFER_TYPE_GAMMA:
 115       return mozilla::wr::ComponentTransferFuncType::Gamma;
 116     case SVG_FECOMPONENTTRANSFER_TYPE_IDENTITY:
 117     default:
 118       return mozilla::wr::ComponentTransferFuncType::Identity;
 119   }
 120   MOZ_ASSERT_UNREACHABLE("all func types not handled?");
 121   return mozilla::wr::ComponentTransferFuncType::Identity;
 122 }
 123
 124 bool FilterInstance::BuildWebRenderFilters(nsIFrame* aFilteredFrame,
 125                                            Span<const StyleFilter> aFilters,
 126                                            WrFiltersHolder& aWrFilters,
 127                                            bool& aInitialized) {
 128   bool status = BuildWebRenderFiltersImpl(aFilteredFrame, aFilters, aWrFilters,
 129                                           aInitialized);
 130   if (!status) {
 131     aFilteredFrame->PresContext()->Document()->SetUseCounter(
 132         eUseCounter_custom_WrFilterFallback);
 133   }
 134
 135   return status;
 136 }
 137
 138 bool FilterInstance::BuildWebRenderFiltersImpl(nsIFrame* aFilteredFrame,
 139                                                Span<const StyleFilter> aFilters,
 140                                                WrFiltersHolder& aWrFilters,
 141                                                bool& aInitialized) {
 142   aWrFilters.filters.Clear();
 143   aWrFilters.filter_datas.Clear();
 144   aWrFilters.values.Clear();
 145
 146   UniquePtr<UserSpaceMetrics> metrics =
 147       UserSpaceMetricsForFrame(aFilteredFrame);
 148
 149   // TODO: simply using an identity matrix here, was pulling the scale from a
 150   // gfx context for the non-wr path.
 151   gfxMatrix scaleMatrix;
 152   gfxMatrix scaleMatrixInDevUnits =
 153       scaleMatrix * SVGUtils::GetCSSPxToDevPxMatrix(aFilteredFrame);
 154
 155   // Hardcode inputIsTainted to true because we don't want JS to be able to
 156   // read the rendered contents of aFilteredFrame.
 157   bool inputIsTainted = true;
 158   FilterInstance instance(aFilteredFrame, aFilteredFrame->GetContent(),
 159                           *metrics, aFilters, inputIsTainted, nullptr,
 160                           scaleMatrixInDevUnits, nullptr, nullptr, nullptr,
 161                           nullptr);
 162
 163   if (!instance.IsInitialized()) {
 164     aInitialized = false;
 165     return true;
 166   }
 167
 168   // If there are too many filters to render, then just pretend that we
 169   // succeeded, and don't render any of them.
 170   if (instance.mFilterDescription.mPrimitives.Length() >
 171       StaticPrefs::gfx_webrender_max_filter_ops_per_chain()) {
 172     return true;
 173   }
 174
 175   Maybe<IntRect> finalClip;
 176   bool srgb = true;
 177   // We currently apply the clip on the stacking context after applying filters,
 178   // but primitive subregions imply clipping after each filter and not just the
 179   // end of the chain. For some types of filter it doesn't matter, but for those
 180   // which sample outside of the location of the destination pixel like blurs,
 181   // only clipping after could produce incorrect results, so we bail out in this
 182   // case.
 183   // We can lift this restriction once we have added support for primitive
 184   // subregions to WebRender's filters.
 185   for (uint32_t i = 0; i < instance.mFilterDescription.mPrimitives.Length();
 186        i++) {
 187     const auto& primitive = instance.mFilterDescription.mPrimitives[i];
 188
 189     // WebRender only supports filters with one input.
 190     if (primitive.NumberOfInputs() != 1) {
 191       return false;
 192     }
 193     // The first primitive must have the source graphic as the input, all
 194     // other primitives must have the prior primitive as the input, otherwise
 195     // it's not supported by WebRender.
 196     if (i == 0) {
 197       if (primitive.InputPrimitiveIndex(0) !=
 198           FilterPrimitiveDescription::kPrimitiveIndexSourceGraphic) {
 199         return false;
 200       }
 201     } else if (primitive.InputPrimitiveIndex(0) != int32_t(i - 1)) {
 202       return false;
 203     }
 204
 205     bool previousSrgb = srgb;
 206     bool primNeedsSrgb = primitive.InputColorSpace(0) == gfx::ColorSpace::SRGB;
 207     if (srgb && !primNeedsSrgb) {
 208       aWrFilters.filters.AppendElement(wr::FilterOp::SrgbToLinear());
 209     } else if (!srgb && primNeedsSrgb) {
 210       aWrFilters.filters.AppendElement(wr::FilterOp::LinearToSrgb());
 211     }
 212     srgb = primitive.OutputColorSpace() == gfx::ColorSpace::SRGB;
 213
 214     const PrimitiveAttributes& attr = primitive.Attributes();
 215
 216     bool filterIsNoop = false;
 217
 218     if (attr.is<OpacityAttributes>()) {
 219       float opacity = attr.as<OpacityAttributes>().mOpacity;
 220       aWrFilters.filters.AppendElement(wr::FilterOp::Opacity(
 221           wr::PropertyBinding<float>::Value(opacity), opacity));
 222     } else if (attr.is<ColorMatrixAttributes>()) {
 223       const ColorMatrixAttributes& attributes =
 224           attr.as<ColorMatrixAttributes>();
 225
 226       float transposed[20];
 227       if (gfx::ComputeColorMatrix(attributes, transposed)) {
 228         float matrix[20] = {
 229             transposed[0], transposed[5], transposed[10], transposed[15],
 230             transposed[1], transposed[6], transposed[11], transposed[16],
 231             transposed[2], transposed[7], transposed[12], transposed[17],
 232             transposed[3], transposed[8], transposed[13], transposed[18],
 233             transposed[4], transposed[9], transposed[14], transposed[19]};
 234
 235         aWrFilters.filters.AppendElement(wr::FilterOp::ColorMatrix(matrix));
 236       } else {
 237         filterIsNoop = true;
 238       }
 239     } else if (attr.is<GaussianBlurAttributes>()) {
 240       if (finalClip) {
 241         // There's a clip that needs to apply before the blur filter, but
 242         // WebRender only lets us apply the clip at the end of the filter
 243         // chain. Clipping after a blur is not equivalent to clipping before
 244         // a blur, so bail out.
 245         return false;
 246       }
 247
 248       const GaussianBlurAttributes& blur = attr.as<GaussianBlurAttributes>();
 249
 250       const Size& stdDev = blur.mStdDeviation;
 251       if (stdDev.width != 0.0 || stdDev.height != 0.0) {
 252         aWrFilters.filters.AppendElement(
 253             wr::FilterOp::Blur(stdDev.width, stdDev.height));
 254       } else {
 255         filterIsNoop = true;
 256       }
 257     } else if (attr.is<DropShadowAttributes>()) {
 258       if (finalClip) {
 259         // We have to bail out for the same reason we would with a blur filter.
 260         return false;
 261       }
 262
 263       const DropShadowAttributes& shadow = attr.as<DropShadowAttributes>();
 264
 265       const Size& stdDev = shadow.mStdDeviation;
 266       if (stdDev.width != stdDev.height) {
 267         return false;
 268       }
 269
 270       sRGBColor color = shadow.mColor;
 271       if (!primNeedsSrgb) {
 272         color = sRGBColor(gsRGBToLinearRGBMap[uint8_t(color.r * 255)],
 273                           gsRGBToLinearRGBMap[uint8_t(color.g * 255)],
 274                           gsRGBToLinearRGBMap[uint8_t(color.b * 255)], color.a);
 275       }
 276       wr::Shadow wrShadow;
 277       wrShadow.offset = {shadow.mOffset.x, shadow.mOffset.y};
 278       wrShadow.color = wr::ToColorF(ToDeviceColor(color));
 279       wrShadow.blur_radius = stdDev.width;
 280       wr::FilterOp filterOp = wr::FilterOp::DropShadow(wrShadow);
 281
 282       aWrFilters.filters.AppendElement(filterOp);
 283     } else if (attr.is<ComponentTransferAttributes>()) {
 284       const ComponentTransferAttributes& attributes =
 285           attr.as<ComponentTransferAttributes>();
 286
 287       size_t numValues =
 288           attributes.mValues[0].Length() + attributes.mValues[1].Length() +
 289           attributes.mValues[2].Length() + attributes.mValues[3].Length();
 290       if (numValues > 1024) {
 291         // Depending on how the wr shaders are implemented we may need to
 292         // limit the total number of values.
 293         return false;
 294       }
 295
 296       wr::FilterOp filterOp = {wr::FilterOp::Tag::ComponentTransfer};
 297       wr::WrFilterData filterData;
 298       aWrFilters.values.AppendElement(nsTArray<float>());
 299       nsTArray<float>* values =
 300           &aWrFilters.values[aWrFilters.values.Length() - 1];
 301       values->SetCapacity(numValues);
 302
 303       filterData.funcR_type = FuncTypeToWr(attributes.mTypes[0]);
 304       size_t R_startindex = values->Length();
 305       values->AppendElements(attributes.mValues[0]);
 306       filterData.R_values_count = attributes.mValues[0].Length();
 307
 308       size_t indexToUse =
 309           attributes.mTypes[1] == SVG_FECOMPONENTTRANSFER_SAME_AS_R ? 0 : 1;
 310       filterData.funcG_type = FuncTypeToWr(attributes.mTypes[indexToUse]);
 311       size_t G_startindex = values->Length();
 312       values->AppendElements(attributes.mValues[indexToUse]);
 313       filterData.G_values_count = attributes.mValues[indexToUse].Length();
 314
 315       indexToUse =
 316           attributes.mTypes[2] == SVG_FECOMPONENTTRANSFER_SAME_AS_R ? 0 : 2;
 317       filterData.funcB_type = FuncTypeToWr(attributes.mTypes[indexToUse]);
 318       size_t B_startindex = values->Length();
 319       values->AppendElements(attributes.mValues[indexToUse]);
 320       filterData.B_values_count = attributes.mValues[indexToUse].Length();
 321
 322       filterData.funcA_type = FuncTypeToWr(attributes.mTypes[3]);
 323       size_t A_startindex = values->Length();
 324       values->AppendElements(attributes.mValues[3]);
 325       filterData.A_values_count = attributes.mValues[3].Length();
 326
 327       filterData.R_values =
 328           filterData.R_values_count > 0 ? &((*values)[R_startindex]) : nullptr;
 329       filterData.G_values =
 330           filterData.G_values_count > 0 ? &((*values)[G_startindex]) : nullptr;
 331       filterData.B_values =
 332           filterData.B_values_count > 0 ? &((*values)[B_startindex]) : nullptr;
 333       filterData.A_values =
 334           filterData.A_values_count > 0 ? &((*values)[A_startindex]) : nullptr;
 335
 336       aWrFilters.filters.AppendElement(filterOp);
 337       aWrFilters.filter_datas.AppendElement(filterData);
 338     } else {
 339       return false;
 340     }
 341
 342     if (filterIsNoop && aWrFilters.filters.Length() > 0 &&
 343         (aWrFilters.filters.LastElement().tag ==
 344              wr::FilterOp::Tag::SrgbToLinear ||
 345          aWrFilters.filters.LastElement().tag ==
 346              wr::FilterOp::Tag::LinearToSrgb)) {
 347       // We pushed a color space conversion filter in prevision of applying
 348       // another filter which turned out to be a no-op, so the conversion is
 349       // unnecessary. Remove it from the filter list.
 350       // This is both an optimization and a way to pass the wptest
 351       // css/filter-effects/filter-scale-001.html for which the needless
 352       // sRGB->linear->no-op->sRGB roundtrip introduces a slight error and we
 353       // cannot add fuzziness to the test.
 354       Unused << aWrFilters.filters.PopLastElement();
 355       srgb = previousSrgb;
 356     }
 357
 358     if (!filterIsNoop) {
 359       if (finalClip.isNothing()) {
 360         finalClip = Some(primitive.PrimitiveSubregion());
 361       } else {
 362         finalClip =
 363             Some(primitive.PrimitiveSubregion().Intersect(finalClip.value()));
 364       }
 365     }
 366   }
 367
 368   if (!srgb) {
 369     aWrFilters.filters.AppendElement(wr::FilterOp::LinearToSrgb());
 370   }
 371
 372   if (finalClip) {
 373     aWrFilters.post_filters_clip =
 374         Some(instance.FilterSpaceToFrameSpace(finalClip.value()));
 375   }
 376   return true;
 377 }
 378
 379 nsRegion FilterInstance::GetPreFilterNeededArea(
 380     nsIFrame* aFilteredFrame, const nsRegion& aPostFilterDirtyRegion) {
 381   gfxMatrix tm = SVGUtils::GetCanvasTM(aFilteredFrame);
 382   auto filterChain = aFilteredFrame->StyleEffects()->mFilters.AsSpan();
 383   UniquePtr<UserSpaceMetrics> metrics =
 384       UserSpaceMetricsForFrame(aFilteredFrame);
 385   // Hardcode InputIsTainted to true because we don't want JS to be able to
 386   // read the rendered contents of aFilteredFrame.
 387   FilterInstance instance(aFilteredFrame, aFilteredFrame->GetContent(),
 388                           *metrics, filterChain, /* InputIsTainted */ true,
 389                           nullptr, tm, &aPostFilterDirtyRegion);
 390   if (!instance.IsInitialized()) {
 391     return nsRect();
 392   }
 393
 394   // Now we can ask the instance to compute the area of the source
 395   // that's needed.
 396   return instance.ComputeSourceNeededRect();
 397 }
 398
 399 Maybe<nsRect> FilterInstance::GetPostFilterBounds(
 400     nsIFrame* aFilteredFrame, const gfxRect* aOverrideBBox,
 401     const nsRect* aPreFilterBounds) {
 402   MOZ_ASSERT(!aFilteredFrame->HasAnyStateBits(NS_FRAME_SVG_LAYOUT) ||
 403                  !aFilteredFrame->HasAnyStateBits(NS_FRAME_IS_NONDISPLAY),
 404              "Non-display SVG do not maintain ink overflow rects");
 405
 406   nsRegion preFilterRegion;
 407   nsRegion* preFilterRegionPtr = nullptr;
 408   if (aPreFilterBounds) {
 409     preFilterRegion = *aPreFilterBounds;
 410     preFilterRegionPtr = &preFilterRegion;
 411   }
 412
 413   gfxMatrix tm = SVGUtils::GetCanvasTM(aFilteredFrame);
 414   auto filterChain = aFilteredFrame->StyleEffects()->mFilters.AsSpan();
 415   UniquePtr<UserSpaceMetrics> metrics =
 416       UserSpaceMetricsForFrame(aFilteredFrame);
 417   // Hardcode InputIsTainted to true because we don't want JS to be able to
 418   // read the rendered contents of aFilteredFrame.
 419   FilterInstance instance(aFilteredFrame, aFilteredFrame->GetContent(),
 420                           *metrics, filterChain, /* InputIsTainted */ true,
 421                           nullptr, tm, nullptr, preFilterRegionPtr,
 422                           aPreFilterBounds, aOverrideBBox);
 423   if (!instance.IsInitialized()) {
 424     return Nothing();
 425   }
 426
 427   return Some(instance.ComputePostFilterExtents());
 428 }
 429
 430 FilterInstance::FilterInstance(
 431     nsIFrame* aTargetFrame, nsIContent* aTargetContent,
 432     const UserSpaceMetrics& aMetrics, Span<const StyleFilter> aFilterChain,
 433     bool aFilterInputIsTainted, const SVGFilterPaintCallback& aPaintCallback,
 434     const gfxMatrix& aPaintTransform, const nsRegion* aPostFilterDirtyRegion,
 435     const nsRegion* aPreFilterDirtyRegion,
 436     const nsRect* aPreFilterInkOverflowRectOverride,
 437     const gfxRect* aOverrideBBox)
 438     : mTargetFrame(aTargetFrame),
 439       mTargetContent(aTargetContent),
 440       mMetrics(aMetrics),
 441       mPaintCallback(aPaintCallback),
 442       mPaintTransform(aPaintTransform),
 443       mInitialized(false) {
 444   if (aOverrideBBox) {
 445     mTargetBBox = *aOverrideBBox;
 446   } else {
 447     MOZ_ASSERT(mTargetFrame,
 448                "Need to supply a frame when there's no aOverrideBBox");
 449     mTargetBBox =
 450         SVGUtils::GetBBox(mTargetFrame, SVGUtils::eUseFrameBoundsForOuterSVG |
 451                                             SVGUtils::eBBoxIncludeFillGeometry);
 452   }
 453
 454   // Compute user space to filter space transforms.
 455   if (!ComputeUserSpaceToFilterSpaceScale()) {
 456     return;
 457   }
 458
 459   if (!ComputeTargetBBoxInFilterSpace()) {
 460     return;
 461   }
 462
 463   // Get various transforms:
 464   gfxMatrix filterToUserSpace(mFilterSpaceToUserSpaceScale.xScale, 0.0f, 0.0f,
 465                               mFilterSpaceToUserSpaceScale.yScale, 0.0f, 0.0f);
 466
 467   mFilterSpaceToFrameSpaceInCSSPxTransform =
 468       filterToUserSpace * GetUserSpaceToFrameSpaceInCSSPxTransform();
 469   // mFilterSpaceToFrameSpaceInCSSPxTransform is always invertible
 470   mFrameSpaceInCSSPxToFilterSpaceTransform =
 471       mFilterSpaceToFrameSpaceInCSSPxTransform;
 472   mFrameSpaceInCSSPxToFilterSpaceTransform.Invert();
 473
 474   nsIntRect targetBounds;
 475   if (aPreFilterInkOverflowRectOverride) {
 476     targetBounds = FrameSpaceToFilterSpace(aPreFilterInkOverflowRectOverride);
 477   } else if (mTargetFrame) {
 478     nsRect preFilterVOR = mTargetFrame->PreEffectsInkOverflowRect();
 479     targetBounds = FrameSpaceToFilterSpace(&preFilterVOR);
 480   }
 481   mTargetBounds.UnionRect(mTargetBBoxInFilterSpace, targetBounds);
 482
 483   // Build the filter graph.
 484   if (NS_FAILED(
 485           BuildPrimitives(aFilterChain, aTargetFrame, aFilterInputIsTainted))) {
 486     return;
 487   }
 488
 489   // Convert the passed in rects from frame space to filter space:
 490   mPostFilterDirtyRegion = FrameSpaceToFilterSpace(aPostFilterDirtyRegion);
 491   mPreFilterDirtyRegion = FrameSpaceToFilterSpace(aPreFilterDirtyRegion);
 492
 493   mInitialized = true;
 494 }
 495
 496 bool FilterInstance::ComputeTargetBBoxInFilterSpace() {
 497   gfxRect targetBBoxInFilterSpace = UserSpaceToFilterSpace(mTargetBBox);
 498   targetBBoxInFilterSpace.RoundOut();
 499
 500   return gfxUtils::GfxRectToIntRect(targetBBoxInFilterSpace,
 501                                     &mTargetBBoxInFilterSpace);
 502 }
 503
 504 bool FilterInstance::ComputeUserSpaceToFilterSpaceScale() {
 505   if (mTargetFrame) {
 506     mUserSpaceToFilterSpaceScale = mPaintTransform.ScaleFactors();
 507     if (mUserSpaceToFilterSpaceScale.xScale <= 0.0f ||
 508         mUserSpaceToFilterSpaceScale.yScale <= 0.0f) {
 509       // Nothing should be rendered.
 510       return false;
 511     }
 512   } else {
 513     mUserSpaceToFilterSpaceScale = MatrixScalesDouble();
 514   }
 515
 516   mFilterSpaceToUserSpaceScale =
 517       MatrixScalesDouble(1.0f / mUserSpaceToFilterSpaceScale.xScale,
 518                          1.0f / mUserSpaceToFilterSpaceScale.yScale);
 519
 520   return true;
 521 }
 522
 523 gfxRect FilterInstance::UserSpaceToFilterSpace(
 524     const gfxRect& aUserSpaceRect) const {
 525   gfxRect filterSpaceRect = aUserSpaceRect;
 526   filterSpaceRect.Scale(mUserSpaceToFilterSpaceScale);
 527   return filterSpaceRect;
 528 }
 529
 530 gfxRect FilterInstance::FilterSpaceToUserSpace(
 531     const gfxRect& aFilterSpaceRect) const {
 532   gfxRect userSpaceRect = aFilterSpaceRect;
 533   userSpaceRect.Scale(mFilterSpaceToUserSpaceScale);
 534   return userSpaceRect;
 535 }
 536
 537 nsresult FilterInstance::BuildPrimitives(Span<const StyleFilter> aFilterChain,
 538                                          nsIFrame* aTargetFrame,
 539                                          bool aFilterInputIsTainted) {
 540   AutoTArray<FilterPrimitiveDescription, 8> primitiveDescriptions;
 541
 542   for (uint32_t i = 0; i < aFilterChain.Length(); i++) {
 543     bool inputIsTainted = primitiveDescriptions.IsEmpty()
 544                               ? aFilterInputIsTainted
 545                               : primitiveDescriptions.LastElement().IsTainted();
 546     nsresult rv = BuildPrimitivesForFilter(
 547         aFilterChain[i], aTargetFrame, inputIsTainted, primitiveDescriptions);
 548     if (NS_FAILED(rv)) {
 549       return rv;
 550     }
 551   }
 552
 553   mFilterDescription = FilterDescription(std::move(primitiveDescriptions));
 554
 555   return NS_OK;
 556 }
 557
 558 nsresult FilterInstance::BuildPrimitivesForFilter(
 559     const StyleFilter& aFilter, nsIFrame* aTargetFrame, bool aInputIsTainted,
 560     nsTArray<FilterPrimitiveDescription>& aPrimitiveDescriptions) {
 561   NS_ASSERTION(mUserSpaceToFilterSpaceScale.xScale > 0.0f &&
 562                    mFilterSpaceToUserSpaceScale.yScale > 0.0f,
 563                "scale factors between spaces should be positive values");
 564
 565   if (aFilter.IsUrl()) {
 566     // Build primitives for an SVG filter.
 567     SVGFilterInstance svgFilterInstance(aFilter, aTargetFrame, mTargetContent,
 568                                         mMetrics, mTargetBBox,
 569                                         mUserSpaceToFilterSpaceScale);
 570     if (!svgFilterInstance.IsInitialized()) {
 571       return NS_ERROR_FAILURE;
 572     }
 573
 574     return svgFilterInstance.BuildPrimitives(aPrimitiveDescriptions,
 575                                              mInputImages, aInputIsTainted);
 576   }
 577
 578   // Build primitives for a CSS filter.
 579
 580   // If we don't have a frame, use opaque black for shadows with unspecified
 581   // shadow colors.
 582   nscolor shadowFallbackColor =
 583       mTargetFrame ? mTargetFrame->StyleText()->mColor.ToColor()
 584                    : NS_RGB(0, 0, 0);
 585
 586   CSSFilterInstance cssFilterInstance(aFilter, shadowFallbackColor,
 587                                       mTargetBounds,
 588                                       mFrameSpaceInCSSPxToFilterSpaceTransform);
 589   return cssFilterInstance.BuildPrimitives(aPrimitiveDescriptions,
 590                                            aInputIsTainted);
 591 }
 592
 593 static void UpdateNeededBounds(const nsIntRegion& aRegion, nsIntRect& aBounds) {
 594   aBounds = aRegion.GetBounds();
 595
 596   bool overflow;
 597   IntSize surfaceSize =
 598       SVGUtils::ConvertToSurfaceSize(SizeDouble(aBounds.Size()), &overflow);
 599   if (overflow) {
 600     aBounds.SizeTo(surfaceSize);
 601   }
 602 }
 603
 604 void FilterInstance::ComputeNeededBoxes() {
 605   if (mFilterDescription.mPrimitives.IsEmpty()) {
 606     return;
 607   }
 608
 609   nsIntRegion sourceGraphicNeededRegion;
 610   nsIntRegion fillPaintNeededRegion;
 611   nsIntRegion strokePaintNeededRegion;
 612
 613   FilterSupport::ComputeSourceNeededRegions(
 614       mFilterDescription, mPostFilterDirtyRegion, sourceGraphicNeededRegion,
 615       fillPaintNeededRegion, strokePaintNeededRegion);
 616
 617   sourceGraphicNeededRegion.And(sourceGraphicNeededRegion, mTargetBounds);
 618
 619   UpdateNeededBounds(sourceGraphicNeededRegion, mSourceGraphic.mNeededBounds);
 620   UpdateNeededBounds(fillPaintNeededRegion, mFillPaint.mNeededBounds);
 621   UpdateNeededBounds(strokePaintNeededRegion, mStrokePaint.mNeededBounds);
 622 }
 623
 624 void FilterInstance::BuildSourcePaint(SourceInfo* aSource,
 625                                       imgDrawingParams& aImgParams) {
 626   MOZ_ASSERT(mTargetFrame);
 627   nsIntRect neededRect = aSource->mNeededBounds;
 628   if (neededRect.IsEmpty()) {
 629     return;
 630   }
 631
 632   RefPtr<DrawTarget> offscreenDT =
 633       gfxPlatform::GetPlatform()->CreateOffscreenContentDrawTarget(
 634           neededRect.Size(), SurfaceFormat::B8G8R8A8);
 635   if (!offscreenDT || !offscreenDT->IsValid()) {
 636     return;
 637   }
 638
 639   gfxContext ctx(offscreenDT);
 640   gfxContextAutoSaveRestore saver(&ctx);
 641
 642   ctx.SetMatrixDouble(mPaintTransform *
 643                       gfxMatrix::Translation(-neededRect.TopLeft()));
 644   GeneralPattern pattern;
 645   if (aSource == &mFillPaint) {
 646     SVGUtils::MakeFillPatternFor(mTargetFrame, &ctx, &pattern, aImgParams);
 647   } else if (aSource == &mStrokePaint) {
 648     SVGUtils::MakeStrokePatternFor(mTargetFrame, &ctx, &pattern, aImgParams);
 649   }
 650
 651   if (pattern.GetPattern()) {
 652     offscreenDT->FillRect(
 653         ToRect(FilterSpaceToUserSpace(ThebesRect(neededRect))), pattern);
 654   }
 655
 656   aSource->mSourceSurface = offscreenDT->Snapshot();
 657   aSource->mSurfaceRect = neededRect;
 658 }
 659
 660 void FilterInstance::BuildSourcePaints(imgDrawingParams& aImgParams) {
 661   if (!mFillPaint.mNeededBounds.IsEmpty()) {
 662     BuildSourcePaint(&mFillPaint, aImgParams);
 663   }
 664
 665   if (!mStrokePaint.mNeededBounds.IsEmpty()) {
 666     BuildSourcePaint(&mStrokePaint, aImgParams);
 667   }
 668 }
 669
 670 void FilterInstance::BuildSourceImage(DrawTarget* aDest,
 671                                       imgDrawingParams& aImgParams,
 672                                       FilterNode* aFilter, FilterNode* aSource,
 673                                       const Rect& aSourceRect) {
 674   MOZ_ASSERT(mTargetFrame);
 675
 676   nsIntRect neededRect = mSourceGraphic.mNeededBounds;
 677   if (neededRect.IsEmpty()) {
 678     return;
 679   }
 680
 681   RefPtr<DrawTarget> offscreenDT;
 682   SurfaceFormat format = SurfaceFormat::B8G8R8A8;
 683   if (aDest->CanCreateSimilarDrawTarget(neededRect.Size(), format)) {
 684     offscreenDT = aDest->CreateSimilarDrawTargetForFilter(
 685         neededRect.Size(), format, aFilter, aSource, aSourceRect, Point(0, 0));
 686   }
 687   if (!offscreenDT || !offscreenDT->IsValid()) {
 688     return;
 689   }
 690
 691   gfxRect r = FilterSpaceToUserSpace(ThebesRect(neededRect));
 692   r.RoundOut();
 693   nsIntRect dirty;
 694   if (!gfxUtils::GfxRectToIntRect(r, &dirty)) {
 695     return;
 696   }
 697
 698   // SVG graphics paint to device space, so we need to set an initial device
 699   // space to filter space transform on the gfxContext that SourceGraphic
 700   // and SourceAlpha will paint to.
 701   //
 702   // (In theory it would be better to minimize error by having filtered SVG
 703   // graphics temporarily paint to user space when painting the sources and
 704   // only set a user space to filter space transform on the gfxContext
 705   // (since that would eliminate the transform multiplications from user
 706   // space to device space and back again). However, that would make the
 707   // code more complex while being hard to get right without introducing
 708   // subtle bugs, and in practice it probably makes no real difference.)
 709   gfxContext ctx(offscreenDT);
 710   gfxMatrix devPxToCssPxTM = SVGUtils::GetCSSPxToDevPxMatrix(mTargetFrame);
 711   DebugOnly<bool> invertible = devPxToCssPxTM.Invert();
 712   MOZ_ASSERT(invertible);
 713   ctx.SetMatrixDouble(devPxToCssPxTM * mPaintTransform *
 714                       gfxMatrix::Translation(-neededRect.TopLeft()));
 715
 716   auto imageFlags = aImgParams.imageFlags;
 717   if (mTargetFrame->HasAnyStateBits(NS_FRAME_IS_NONDISPLAY)) {
 718     // We're coming from a mask or pattern instance. Patterns
 719     // are painted into a separate surface and it seems we can't
 720     // handle the differently sized surface that might be returned
 721     // with FLAG_HIGH_QUALITY_SCALING
 722     imageFlags &= ~imgIContainer::FLAG_HIGH_QUALITY_SCALING;
 723   }
 724   imgDrawingParams imgParams(imageFlags);
 725   mPaintCallback(ctx, imgParams, &mPaintTransform, &dirty);
 726   aImgParams.result = imgParams.result;
 727
 728   mSourceGraphic.mSourceSurface = offscreenDT->Snapshot();
 729   mSourceGraphic.mSurfaceRect = neededRect;
 730 }
 731
 732 void FilterInstance::Render(gfxContext* aCtx, imgDrawingParams& aImgParams,
 733                             float aOpacity) {
 734   MOZ_ASSERT(mTargetFrame, "Need a frame for rendering");
 735
 736   if (mFilterDescription.mPrimitives.IsEmpty()) {
 737     // An filter without any primitive. Treat it as success and paint nothing.
 738     return;
 739   }
 740
 741   nsIntRect filterRect =
 742       mPostFilterDirtyRegion.GetBounds().Intersect(OutputFilterSpaceBounds());
 743   if (filterRect.IsEmpty() || mPaintTransform.IsSingular()) {
 744     return;
 745   }
 746
 747   gfxContextMatrixAutoSaveRestore autoSR(aCtx);
 748   aCtx->SetMatrix(
 749       aCtx->CurrentMatrix().PreTranslate(filterRect.x, filterRect.y));
 750
 751   ComputeNeededBoxes();
 752
 753   Rect renderRect = IntRectToRect(filterRect);
 754   RefPtr<DrawTarget> dt = aCtx->GetDrawTarget();
 755
 756   MOZ_ASSERT(dt);
 757   if (!dt->IsValid()) {
 758     return;
 759   }
 760
 761   BuildSourcePaints(aImgParams);
 762   RefPtr<FilterNode> sourceGraphic, fillPaint, strokePaint;
 763   if (mFillPaint.mSourceSurface) {
 764     fillPaint = FilterWrappers::ForSurface(dt, mFillPaint.mSourceSurface,
 765                                            mFillPaint.mSurfaceRect.TopLeft());
 766   }
 767   if (mStrokePaint.mSourceSurface) {
 768     strokePaint = FilterWrappers::ForSurface(
 769         dt, mStrokePaint.mSourceSurface, mStrokePaint.mSurfaceRect.TopLeft());
 770   }
 771
 772   // We make the sourceGraphic filter but don't set its inputs until after so
 773   // that we can make the sourceGraphic size depend on the filter chain
 774   sourceGraphic = dt->CreateFilter(FilterType::TRANSFORM);
 775   if (sourceGraphic) {
 776     // Make sure we set the translation before calling BuildSourceImage
 777     // so that CreateSimilarDrawTargetForFilter works properly
 778     IntPoint offset = mSourceGraphic.mNeededBounds.TopLeft();
 779     sourceGraphic->SetAttribute(ATT_TRANSFORM_MATRIX,
 780                                 Matrix::Translation(offset.x, offset.y));
 781   }
 782
 783   RefPtr<FilterNode> resultFilter = FilterNodeGraphFromDescription(
 784       dt, mFilterDescription, renderRect, sourceGraphic,
 785       mSourceGraphic.mSurfaceRect, fillPaint, strokePaint, mInputImages);
 786
 787   if (!resultFilter) {
 788     gfxWarning() << "Filter is NULL.";
 789     return;
 790   }
 791
 792   BuildSourceImage(dt, aImgParams, resultFilter, sourceGraphic, renderRect);
 793   if (sourceGraphic) {
 794     if (mSourceGraphic.mSourceSurface) {
 795       sourceGraphic->SetInput(IN_TRANSFORM_IN, mSourceGraphic.mSourceSurface);
 796     } else {
 797       RefPtr<FilterNode> clear = FilterWrappers::Clear(aCtx->GetDrawTarget());
 798       sourceGraphic->SetInput(IN_TRANSFORM_IN, clear);
 799     }
 800   }
 801
 802   dt->DrawFilter(resultFilter, renderRect, Point(0, 0), DrawOptions(aOpacity));
 803 }
 804
 805 nsRegion FilterInstance::ComputePostFilterDirtyRegion() {
 806   if (mPreFilterDirtyRegion.IsEmpty() ||
 807       mFilterDescription.mPrimitives.IsEmpty()) {
 808     return nsRegion();
 809   }
 810
 811   nsIntRegion resultChangeRegion = FilterSupport::ComputeResultChangeRegion(
 812       mFilterDescription, mPreFilterDirtyRegion, nsIntRegion(), nsIntRegion());
 813   return FilterSpaceToFrameSpace(resultChangeRegion);
 814 }
 815
 816 nsRect FilterInstance::ComputePostFilterExtents() {
 817   if (mFilterDescription.mPrimitives.IsEmpty()) {
 818     return nsRect();
 819   }
 820
 821   nsIntRegion postFilterExtents = FilterSupport::ComputePostFilterExtents(
 822       mFilterDescription, mTargetBounds);
 823   return FilterSpaceToFrameSpace(postFilterExtents.GetBounds());
 824 }
 825
 826 nsRect FilterInstance::ComputeSourceNeededRect() {
 827   ComputeNeededBoxes();
 828   return FilterSpaceToFrameSpace(mSourceGraphic.mNeededBounds);
 829 }
 830
 831 nsIntRect FilterInstance::OutputFilterSpaceBounds() const {
 832   uint32_t numPrimitives = mFilterDescription.mPrimitives.Length();
 833   if (numPrimitives <= 0) {
 834     return nsIntRect();
 835   }
 836
 837   return mFilterDescription.mPrimitives[numPrimitives - 1].PrimitiveSubregion();
 838 }
 839
 840 nsIntRect FilterInstance::FrameSpaceToFilterSpace(const nsRect* aRect) const {
 841   nsIntRect rect = OutputFilterSpaceBounds();
 842   if (aRect) {
 843     if (aRect->IsEmpty()) {
 844       return nsIntRect();
 845     }
 846     gfxRect rectInCSSPx =
 847         nsLayoutUtils::RectToGfxRect(*aRect, AppUnitsPerCSSPixel());
 848     gfxRect rectInFilterSpace =
 849         mFrameSpaceInCSSPxToFilterSpaceTransform.TransformBounds(rectInCSSPx);
 850     rectInFilterSpace.RoundOut();
 851     nsIntRect intRect;
 852     if (gfxUtils::GfxRectToIntRect(rectInFilterSpace, &intRect)) {
 853       rect = intRect;
 854     }
 855   }
 856   return rect;
 857 }
 858
 859 nsRect FilterInstance::FilterSpaceToFrameSpace(const nsIntRect& aRect) const {
 860   if (aRect.IsEmpty()) {
 861     return nsRect();
 862   }
 863   gfxRect r(aRect.x, aRect.y, aRect.width, aRect.height);
 864   r = mFilterSpaceToFrameSpaceInCSSPxTransform.TransformBounds(r);
 865   // nsLayoutUtils::RoundGfxRectToAppRect rounds out.
 866   return nsLayoutUtils::RoundGfxRectToAppRect(r, AppUnitsPerCSSPixel());
 867 }
 868
 869 nsIntRegion FilterInstance::FrameSpaceToFilterSpace(
 870     const nsRegion* aRegion) const {
 871   if (!aRegion) {
 872     return OutputFilterSpaceBounds();
 873   }
 874   nsIntRegion result;
 875   for (auto iter = aRegion->RectIter(); !iter.Done(); iter.Next()) {
 876     // FrameSpaceToFilterSpace rounds out, so this works.
 877     nsRect rect = iter.Get();
 878     result.Or(result, FrameSpaceToFilterSpace(&rect));
 879   }
 880   return result;
 881 }
 882
 883 nsRegion FilterInstance::FilterSpaceToFrameSpace(
 884     const nsIntRegion& aRegion) const {
 885   nsRegion result;
 886   for (auto iter = aRegion.RectIter(); !iter.Done(); iter.Next()) {
 887     // FilterSpaceToFrameSpace rounds out, so this works.
 888     result.Or(result, FilterSpaceToFrameSpace(iter.Get()));
 889   }
 890   return result;
 891 }
 892
 893 gfxMatrix FilterInstance::GetUserSpaceToFrameSpaceInCSSPxTransform() const {
 894   if (!mTargetFrame) {
 895     return gfxMatrix();
 896   }
 897   return gfxMatrix::Translation(
 898       -SVGUtils::FrameSpaceInCSSPxToUserSpaceOffset(mTargetFrame));
 899 }
 900
 901 }  // namespace mozilla