DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Header

Mercurial (5b81998bb7ab)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

// Main header first:
#include "nsSVGPatternFrame.h"

// Keep others in (case-insensitive) order:
#include "gfxContext.h"
#include "gfxMatrix.h"
#include "gfxPattern.h"
#include "gfxPlatform.h"
#include "nsContentUtils.h"
#include "nsGkAtoms.h"
#include "nsISVGChildFrame.h"
#include "nsRenderingContext.h"
#include "nsStyleContext.h"
#include "nsSVGEffects.h"
#include "nsSVGGeometryFrame.h"
#include "nsSVGPatternElement.h"
#include "nsSVGUtils.h"
#include "SVGAnimatedTransformList.h"
#include "SVGContentUtils.h"

using namespace mozilla;

//----------------------------------------------------------------------
// Helper classes

class nsSVGPatternFrame::AutoPatternReferencer
{
public:
  AutoPatternReferencer(nsSVGPatternFrame *aFrame)
    : mFrame(aFrame)
  {
    // Reference loops should normally be detected in advance and handled, so
    // we're not expecting to encounter them here
    NS_ABORT_IF_FALSE(!mFrame->mLoopFlag, "Undetected reference loop!");
    mFrame->mLoopFlag = true;
  }
  ~AutoPatternReferencer() {
    mFrame->mLoopFlag = false;
  }
private:
  nsSVGPatternFrame *mFrame;
};

//----------------------------------------------------------------------
// Implementation

nsSVGPatternFrame::nsSVGPatternFrame(nsStyleContext* aContext) :
  nsSVGPatternFrameBase(aContext),
  mLoopFlag(false),
  mNoHRefURI(false)
{
}

NS_IMPL_FRAMEARENA_HELPERS(nsSVGPatternFrame)

//----------------------------------------------------------------------
// nsIFrame methods:

/* virtual */ void
nsSVGPatternFrame::DidSetStyleContext(nsStyleContext* aOldStyleContext)
{
  nsSVGEffects::InvalidateDirectRenderingObservers(this);
  nsSVGPatternFrameBase::DidSetStyleContext(aOldStyleContext);
}

NS_IMETHODIMP
nsSVGPatternFrame::AttributeChanged(int32_t         aNameSpaceID,
                                    nsIAtom*        aAttribute,
                                    int32_t         aModType)
{
  if (aNameSpaceID == kNameSpaceID_None &&
      (aAttribute == nsGkAtoms::patternUnits ||
       aAttribute == nsGkAtoms::patternContentUnits ||
       aAttribute == nsGkAtoms::patternTransform ||
       aAttribute == nsGkAtoms::x ||
       aAttribute == nsGkAtoms::y ||
       aAttribute == nsGkAtoms::width ||
       aAttribute == nsGkAtoms::height ||
       aAttribute == nsGkAtoms::preserveAspectRatio ||
       aAttribute == nsGkAtoms::viewBox)) {
    nsSVGEffects::InvalidateDirectRenderingObservers(this);
  }

  if (aNameSpaceID == kNameSpaceID_XLink &&
      aAttribute == nsGkAtoms::href) {
    // Blow away our reference, if any
    Properties().Delete(nsSVGEffects::HrefProperty());
    mNoHRefURI = false;
    // And update whoever references us
    nsSVGEffects::InvalidateDirectRenderingObservers(this);
  }

  return nsSVGPatternFrameBase::AttributeChanged(aNameSpaceID,
                                                 aAttribute, aModType);
}

#ifdef DEBUG
NS_IMETHODIMP
nsSVGPatternFrame::Init(nsIContent* aContent,
                        nsIFrame* aParent,
                        nsIFrame* aPrevInFlow)
{
  nsCOMPtr<nsIDOMSVGPatternElement> patternElement = do_QueryInterface(aContent);
  NS_ASSERTION(patternElement, "Content is not an SVG pattern");

  return nsSVGPatternFrameBase::Init(aContent, aParent, aPrevInFlow);
}
#endif /* DEBUG */

nsIAtom*
nsSVGPatternFrame::GetType() const
{
  return nsGkAtoms::svgPatternFrame;
}

//----------------------------------------------------------------------
// nsSVGContainerFrame methods:

// If our GetCanvasTM is getting called, we
// need to return *our current* transformation
// matrix, which depends on our units parameters
// and X, Y, Width, and Height
gfxMatrix
nsSVGPatternFrame::GetCanvasTM(uint32_t aFor)
{
  if (mCTM) {
    return *mCTM;
  }

  // Do we know our rendering parent?
  if (mSource) {
    // Yes, use it!
    return mSource->GetCanvasTM(aFor);
  }

  // We get here when geometry in the <pattern> container is updated
  return gfxMatrix();
}

// -------------------------------------------------------------------------
// Helper functions
// -------------------------------------------------------------------------

// The SVG specification says that the 'patternContentUnits' attribute "has no effect if
// attribute ‘viewBox’ is specified". We still need to include a bbox scale
// if the viewBox is specified and _patternUnits_ is set to or defaults to
// objectBoundingBox though, since in that case the viewBox is relative to the bbox
static bool
IncludeBBoxScale(const nsSVGViewBox& aViewBox,
                 uint32_t aPatternContentUnits, uint32_t aPatternUnits)
{
  return (!aViewBox.IsExplicitlySet() &&
          aPatternContentUnits == nsIDOMSVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) ||
         (aViewBox.IsExplicitlySet() &&
          aPatternUnits == nsIDOMSVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX);
}

// Given the matrix for the pattern element's own transform, this returns a
// combined matrix including the transforms applicable to its target.
static gfxMatrix
GetPatternMatrix(uint16_t aPatternUnits,
                 const gfxMatrix &patternTransform,
                 const gfxRect &bbox,
                 const gfxRect &callerBBox,
                 const gfxMatrix &callerCTM)
{
  // We really want the pattern matrix to handle translations
  gfxFloat minx = bbox.X();
  gfxFloat miny = bbox.Y();

  if (aPatternUnits == nsIDOMSVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) {
    minx += callerBBox.X();
    miny += callerBBox.Y();
  }

  float scale = 1.0f / nsSVGUtils::MaxExpansion(callerCTM);
  gfxMatrix patternMatrix = patternTransform;
  patternMatrix.Scale(scale, scale);
  patternMatrix.Translate(gfxPoint(minx, miny));

  return patternMatrix;
}

static nsresult
GetTargetGeometry(gfxRect *aBBox,
                  const nsSVGViewBox &aViewBox,
                  uint16_t aPatternContentUnits,
                  uint16_t aPatternUnits,
                  nsIFrame *aTarget,
                  const gfxMatrix &aContextMatrix,
                  const gfxRect *aOverrideBounds)
{
  *aBBox = aOverrideBounds ? *aOverrideBounds : nsSVGUtils::GetBBox(aTarget);

  // Sanity check
  if (IncludeBBoxScale(aViewBox, aPatternContentUnits, aPatternUnits) &&
      (aBBox->Width() <= 0 || aBBox->Height() <= 0)) {
    return NS_ERROR_FAILURE;
  }

  // OK, now fix up the bounding box to reflect user coordinates
  // We handle device unit scaling in pattern matrix
  float scale = nsSVGUtils::MaxExpansion(aContextMatrix);
  if (scale <= 0) {
    return NS_ERROR_FAILURE;
  }
  aBBox->Scale(scale);
  return NS_OK;
}

nsresult
nsSVGPatternFrame::PaintPattern(gfxASurface** surface,
                                gfxMatrix* patternMatrix,
                                const gfxMatrix &aContextMatrix,
                                nsIFrame *aSource,
                                nsStyleSVGPaint nsStyleSVG::*aFillOrStroke,
                                float aGraphicOpacity,
                                const gfxRect *aOverrideBounds)
{
  /*
   * General approach:
   *    Set the content geometry stuff
   *    Calculate our bbox (using x,y,width,height & patternUnits &
   *                        patternTransform)
   *    Create the surface
   *    Calculate the content transformation matrix
   *    Get our children (we may need to get them from another Pattern)
   *    Call SVGPaint on all of our children
   *    Return
   */
  *surface = nullptr;

  // Get the first child of the pattern data we will render
  nsIFrame* firstKid = GetPatternFirstChild();
  if (!firstKid)
    return NS_ERROR_FAILURE; // Either no kids or a bad reference

  const nsSVGViewBox& viewBox = GetViewBox();

  uint16_t patternContentUnits =
    GetEnumValue(nsSVGPatternElement::PATTERNCONTENTUNITS);
  uint16_t patternUnits =
    GetEnumValue(nsSVGPatternElement::PATTERNUNITS);

  /*
   * Get the content geometry information.  This is a little tricky --
   * our parent is probably a <defs>, but we are rendering in the context
   * of some geometry source.  Our content geometry information needs to
   * come from our rendering parent as opposed to our content parent.  We
   * get that information from aSource, which is passed to us from the
   * backend renderer.
   *
   * There are three "geometries" that we need:
   *   1) The bounding box for the pattern.  We use this to get the
   *      width and height for the surface, and as the return to
   *      GetBBox.
   *   2) The transformation matrix for the pattern.  This is not *quite*
   *      the same as the canvas transformation matrix that we will
   *      provide to our rendering children since we "fudge" it a little
   *      to get the renderer to handle the translations correctly for us.
   *   3) The CTM that we return to our children who make up the pattern.
   */

  // Get all of the information we need from our "caller" -- i.e.
  // the geometry that is being rendered with a pattern
  gfxRect callerBBox;
  if (NS_FAILED(GetTargetGeometry(&callerBBox,
                                  viewBox,
                                  patternContentUnits, patternUnits,
                                  aSource,
                                  aContextMatrix,
                                  aOverrideBounds)))
    return NS_ERROR_FAILURE;

  // Construct the CTM that we will provide to our children when we
  // render them into the tile.
  gfxMatrix ctm = ConstructCTM(viewBox, patternContentUnits, patternUnits,
                               callerBBox, aContextMatrix, aSource);
  if (ctm.IsSingular()) {
    return NS_ERROR_FAILURE;
  }

  // Get the pattern we are going to render
  nsSVGPatternFrame *patternFrame =
    static_cast<nsSVGPatternFrame*>(firstKid->GetParent());
  if (patternFrame->mCTM) {
    *patternFrame->mCTM = ctm;
  } else {
    patternFrame->mCTM = new gfxMatrix(ctm);
  }

  // Get the bounding box of the pattern.  This will be used to determine
  // the size of the surface, and will also be used to define the bounding
  // box for the pattern tile.
  gfxRect bbox = GetPatternRect(patternUnits, callerBBox, aContextMatrix, aSource);

  // Get the pattern transform
  gfxMatrix patternTransform = GetPatternTransform();

  // revert the vector effect transform so that the pattern appears unchanged
  if (aFillOrStroke == &nsStyleSVG::mStroke) {
    patternTransform.Multiply(nsSVGUtils::GetStrokeTransform(aSource).Invert());
  }

  // Get the transformation matrix that we will hand to the renderer's pattern
  // routine.
  *patternMatrix = GetPatternMatrix(patternUnits, patternTransform,
                                    bbox, callerBBox, aContextMatrix);
  if (patternMatrix->IsSingular()) {
    return NS_ERROR_FAILURE;
  }

  // Now that we have all of the necessary geometries, we can
  // create our surface.
  gfxRect transformedBBox = patternTransform.TransformBounds(bbox);

  bool resultOverflows;
  gfxIntSize surfaceSize =
    nsSVGUtils::ConvertToSurfaceSize(
      transformedBBox.Size(), &resultOverflows);

  // 0 disables rendering, < 0 is an error
  if (surfaceSize.width <= 0 || surfaceSize.height <= 0)
    return NS_ERROR_FAILURE;

  gfxFloat patternWidth = bbox.Width();
  gfxFloat patternHeight = bbox.Height();

  if (resultOverflows ||
      patternWidth != surfaceSize.width ||
      patternHeight != surfaceSize.height) {
    // scale drawing to pattern surface size
    gfxMatrix tempTM =
      gfxMatrix(surfaceSize.width / patternWidth, 0.0f,
                0.0f, surfaceSize.height / patternHeight,
                0.0f, 0.0f);
    patternFrame->mCTM->PreMultiply(tempTM);

    // and rescale pattern to compensate
    patternMatrix->Scale(patternWidth / surfaceSize.width,
                         patternHeight / surfaceSize.height);
  }

  nsRefPtr<gfxASurface> tmpSurface =
    gfxPlatform::GetPlatform()->CreateOffscreenSurface(surfaceSize,
                                                       gfxASurface::CONTENT_COLOR_ALPHA);
  if (!tmpSurface || tmpSurface->CairoStatus())
    return NS_ERROR_FAILURE;

  nsRenderingContext context;
  context.Init(aSource->PresContext()->DeviceContext(), tmpSurface);
  gfxContext* gfx = context.ThebesContext();

  // Fill with transparent black
  gfx->SetOperator(gfxContext::OPERATOR_CLEAR);
  gfx->Paint();
  gfx->SetOperator(gfxContext::OPERATOR_OVER);

  if (aGraphicOpacity != 1.0f) {
    gfx->Save();
    gfx->PushGroup(gfxASurface::CONTENT_COLOR_ALPHA);
  }

  // OK, now render -- note that we use "firstKid", which
  // we got at the beginning because it takes care of the
  // referenced pattern situation for us

  if (aSource->IsFrameOfType(nsIFrame::eSVGGeometry)) {
    // Set the geometrical parent of the pattern we are rendering
    patternFrame->mSource = static_cast<nsSVGGeometryFrame*>(aSource);
  }

  // Delay checking NS_FRAME_DRAWING_AS_PAINTSERVER bit until here so we can
  // give back a clear surface if there's a loop
  if (!(patternFrame->GetStateBits() & NS_FRAME_DRAWING_AS_PAINTSERVER)) {
    patternFrame->AddStateBits(NS_FRAME_DRAWING_AS_PAINTSERVER);
    for (nsIFrame* kid = firstKid; kid;
         kid = kid->GetNextSibling()) {
      // The CTM of each frame referencing us can be different
      nsISVGChildFrame* SVGFrame = do_QueryFrame(kid);
      if (SVGFrame) {
        SVGFrame->NotifySVGChanged(nsISVGChildFrame::TRANSFORM_CHANGED);
      }
      nsSVGUtils::PaintFrameWithEffects(&context, nullptr, kid);
    }
    patternFrame->RemoveStateBits(NS_FRAME_DRAWING_AS_PAINTSERVER);
  }

  patternFrame->mSource = nullptr;

  if (aGraphicOpacity != 1.0f) {
    gfx->PopGroupToSource();
    gfx->Paint(aGraphicOpacity);
    gfx->Restore();
  }

  // caller now owns the surface
  tmpSurface.forget(surface);
  return NS_OK;
}

/* Will probably need something like this... */
// How do we handle the insertion of a new frame?
// We really don't want to rerender this every time,
// do we?
nsIFrame*
nsSVGPatternFrame::GetPatternFirstChild()
{
  // Do we have any children ourselves?
  nsIFrame* kid = mFrames.FirstChild();
  if (kid)
    return kid;

  // No, see if we chain to someone who does
  AutoPatternReferencer patternRef(this);

  nsSVGPatternFrame* next = GetReferencedPatternIfNotInUse();
  if (!next)
    return nullptr;

  return next->GetPatternFirstChild();
}

uint16_t
nsSVGPatternFrame::GetEnumValue(uint32_t aIndex, nsIContent *aDefault)
{
  nsSVGEnum& thisEnum =
    static_cast<nsSVGPatternElement *>(mContent)->mEnumAttributes[aIndex];

  if (thisEnum.IsExplicitlySet())
    return thisEnum.GetAnimValue();

  AutoPatternReferencer patternRef(this);

  nsSVGPatternFrame *next = GetReferencedPatternIfNotInUse();
  return next ? next->GetEnumValue(aIndex, aDefault) :
    static_cast<nsSVGPatternElement *>(aDefault)->
      mEnumAttributes[aIndex].GetAnimValue();
}

SVGAnimatedTransformList*
nsSVGPatternFrame::GetPatternTransformList(nsIContent* aDefault)
{
  SVGAnimatedTransformList *thisTransformList =
    static_cast<nsSVGPatternElement *>(mContent)->GetAnimatedTransformList();

  if (thisTransformList && thisTransformList->IsExplicitlySet())
    return thisTransformList;

  AutoPatternReferencer patternRef(this);

  nsSVGPatternFrame *next = GetReferencedPatternIfNotInUse();
  return next ? next->GetPatternTransformList(aDefault) :
    static_cast<nsSVGPatternElement *>(aDefault)->mPatternTransform.get();
}

gfxMatrix
nsSVGPatternFrame::GetPatternTransform()
{
  SVGAnimatedTransformList* animTransformList =
    GetPatternTransformList(mContent);
  if (!animTransformList)
    return gfxMatrix();

  return animTransformList->GetAnimValue().GetConsolidationMatrix();
}

const nsSVGViewBox &
nsSVGPatternFrame::GetViewBox(nsIContent* aDefault)
{
  const nsSVGViewBox &thisViewBox =
    static_cast<nsSVGPatternElement *>(mContent)->mViewBox;

  if (thisViewBox.IsExplicitlySet())
    return thisViewBox;

  AutoPatternReferencer patternRef(this);

  nsSVGPatternFrame *next = GetReferencedPatternIfNotInUse();
  return next ? next->GetViewBox(aDefault) :
    static_cast<nsSVGPatternElement *>(aDefault)->mViewBox;
}

const SVGAnimatedPreserveAspectRatio &
nsSVGPatternFrame::GetPreserveAspectRatio(nsIContent *aDefault)
{
  const SVGAnimatedPreserveAspectRatio &thisPar =
    static_cast<nsSVGPatternElement *>(mContent)->mPreserveAspectRatio;

  if (thisPar.IsExplicitlySet())
    return thisPar;

  AutoPatternReferencer patternRef(this);

  nsSVGPatternFrame *next = GetReferencedPatternIfNotInUse();
  return next ? next->GetPreserveAspectRatio(aDefault) :
    static_cast<nsSVGPatternElement *>(aDefault)->mPreserveAspectRatio;
}

const nsSVGLength2 *
nsSVGPatternFrame::GetLengthValue(uint32_t aIndex, nsIContent *aDefault)
{
  const nsSVGLength2 *thisLength =
    &static_cast<nsSVGPatternElement *>(mContent)->mLengthAttributes[aIndex];

  if (thisLength->IsExplicitlySet())
    return thisLength;

  AutoPatternReferencer patternRef(this);

  nsSVGPatternFrame *next = GetReferencedPatternIfNotInUse();
  return next ? next->GetLengthValue(aIndex, aDefault) :
    &static_cast<nsSVGPatternElement *>(aDefault)->mLengthAttributes[aIndex];
}

// Private (helper) methods
nsSVGPatternFrame *
nsSVGPatternFrame::GetReferencedPattern()
{
  if (mNoHRefURI)
    return nullptr;

  nsSVGPaintingProperty *property = static_cast<nsSVGPaintingProperty*>
    (Properties().Get(nsSVGEffects::HrefProperty()));

  if (!property) {
    // Fetch our pattern element's xlink:href attribute
    nsSVGPatternElement *pattern = static_cast<nsSVGPatternElement *>(mContent);
    nsAutoString href;
    pattern->mStringAttributes[nsSVGPatternElement::HREF].GetAnimValue(href, pattern);
    if (href.IsEmpty()) {
      mNoHRefURI = true;
      return nullptr; // no URL
    }

    // Convert href to an nsIURI
    nsCOMPtr<nsIURI> targetURI;
    nsCOMPtr<nsIURI> base = mContent->GetBaseURI();
    nsContentUtils::NewURIWithDocumentCharset(getter_AddRefs(targetURI), href,
                                              mContent->GetCurrentDoc(), base);

    property =
      nsSVGEffects::GetPaintingProperty(targetURI, this, nsSVGEffects::HrefProperty());
    if (!property)
      return nullptr;
  }

  nsIFrame *result = property->GetReferencedFrame();
  if (!result)
    return nullptr;

  nsIAtom* frameType = result->GetType();
  if (frameType != nsGkAtoms::svgPatternFrame)
    return nullptr;

  return static_cast<nsSVGPatternFrame*>(result);
}

nsSVGPatternFrame *
nsSVGPatternFrame::GetReferencedPatternIfNotInUse()
{
  nsSVGPatternFrame *referenced = GetReferencedPattern();
  if (!referenced)
    return nullptr;

  if (referenced->mLoopFlag) {
    // XXXjwatt: we should really send an error to the JavaScript Console here:
    NS_WARNING("pattern reference loop detected while inheriting attribute!");
    return nullptr;
  }

  return referenced;
}

gfxRect
nsSVGPatternFrame::GetPatternRect(uint16_t aPatternUnits,
                                  const gfxRect &aTargetBBox,
                                  const gfxMatrix &aTargetCTM,
                                  nsIFrame *aTarget)
{
  // We need to initialize our box
  float x,y,width,height;

  // Get the pattern x,y,width, and height
  const nsSVGLength2 *tmpX, *tmpY, *tmpHeight, *tmpWidth;
  tmpX = GetLengthValue(nsSVGPatternElement::X);
  tmpY = GetLengthValue(nsSVGPatternElement::Y);
  tmpHeight = GetLengthValue(nsSVGPatternElement::HEIGHT);
  tmpWidth = GetLengthValue(nsSVGPatternElement::WIDTH);

  if (aPatternUnits == nsIDOMSVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) {
    x = nsSVGUtils::ObjectSpace(aTargetBBox, tmpX);
    y = nsSVGUtils::ObjectSpace(aTargetBBox, tmpY);
    width = nsSVGUtils::ObjectSpace(aTargetBBox, tmpWidth);
    height = nsSVGUtils::ObjectSpace(aTargetBBox, tmpHeight);
  } else {
    float scale = nsSVGUtils::MaxExpansion(aTargetCTM);
    x = nsSVGUtils::UserSpace(aTarget, tmpX) * scale;
    y = nsSVGUtils::UserSpace(aTarget, tmpY) * scale;
    width = nsSVGUtils::UserSpace(aTarget, tmpWidth) * scale;
    height = nsSVGUtils::UserSpace(aTarget, tmpHeight) * scale;
  }

  return gfxRect(x, y, width, height);
}

gfxMatrix
nsSVGPatternFrame::ConstructCTM(const nsSVGViewBox& aViewBox,
                                uint16_t aPatternContentUnits,
                                uint16_t aPatternUnits,
                                const gfxRect &callerBBox,
                                const gfxMatrix &callerCTM,
                                nsIFrame *aTarget)
{
  gfxMatrix tCTM;
  nsSVGSVGElement *ctx = nullptr;
  nsIContent* targetContent = aTarget->GetContent();

  // The objectBoundingBox conversion must be handled in the CTM:
  if (IncludeBBoxScale(aViewBox, aPatternContentUnits, aPatternUnits)) {
    tCTM.Scale(callerBBox.Width(), callerBBox.Height());
  } else {
    if (targetContent->IsSVG()) {
      ctx = static_cast<nsSVGElement*>(targetContent)->GetCtx();
    }
    float scale = nsSVGUtils::MaxExpansion(callerCTM);
    tCTM.Scale(scale, scale);
  }

  if (!aViewBox.IsExplicitlySet()) {
    return tCTM;
  }
  const nsSVGViewBoxRect viewBoxRect = aViewBox.GetAnimValue();

  if (viewBoxRect.height <= 0.0f || viewBoxRect.width <= 0.0f) {
    return gfxMatrix(0.0, 0.0, 0.0, 0.0, 0.0, 0.0); // singular
  }

  float viewportWidth, viewportHeight;
  if (targetContent->IsSVG()) {
    // If we're dealing with an SVG target only retrieve the context once.
    // Calling the nsIFrame* variant of GetAnimValue would look it up on
    // every call.
    viewportWidth =
      GetLengthValue(nsSVGPatternElement::WIDTH)->GetAnimValue(ctx);
    viewportHeight =
      GetLengthValue(nsSVGPatternElement::HEIGHT)->GetAnimValue(ctx);
  } else {
    // No SVG target, call the nsIFrame* variant of GetAnimValue.
    viewportWidth =
      GetLengthValue(nsSVGPatternElement::WIDTH)->GetAnimValue(aTarget);
    viewportHeight =
      GetLengthValue(nsSVGPatternElement::HEIGHT)->GetAnimValue(aTarget);
  }

  if (viewportWidth <= 0.0f || viewportHeight <= 0.0f) {
    return gfxMatrix(0.0, 0.0, 0.0, 0.0, 0.0, 0.0); // singular
  }

  gfxMatrix tm = SVGContentUtils::GetViewBoxTransform(
    static_cast<nsSVGPatternElement*>(mContent),
    viewportWidth, viewportHeight,
    viewBoxRect.x, viewBoxRect.y,
    viewBoxRect.width, viewBoxRect.height,
    GetPreserveAspectRatio());

  return tm * tCTM;
}

//----------------------------------------------------------------------
// nsSVGPaintServerFrame methods:

already_AddRefed<gfxPattern>
nsSVGPatternFrame::GetPaintServerPattern(nsIFrame *aSource,
                                         const gfxMatrix& aContextMatrix,
                                         nsStyleSVGPaint nsStyleSVG::*aFillOrStroke,
                                         float aGraphicOpacity,
                                         const gfxRect *aOverrideBounds)
{
  if (aGraphicOpacity == 0.0f) {
    nsRefPtr<gfxPattern> pattern = new gfxPattern(gfxRGBA(0, 0, 0, 0));
    return pattern.forget();
  }

  // Paint it!
  nsRefPtr<gfxASurface> surface;
  gfxMatrix pMatrix;
  nsresult rv = PaintPattern(getter_AddRefs(surface), &pMatrix, aContextMatrix,
                             aSource, aFillOrStroke, aGraphicOpacity, aOverrideBounds);

  if (NS_FAILED(rv)) {
    return nullptr;
  }

  pMatrix.Invert();

  nsRefPtr<gfxPattern> pattern = new gfxPattern(surface);

  if (!pattern || pattern->CairoStatus())
    return nullptr;

  pattern->SetMatrix(pMatrix);
  pattern->SetExtend(gfxPattern::EXTEND_REPEAT);
  return pattern.forget();
}

// -------------------------------------------------------------------------
// Public functions
// -------------------------------------------------------------------------

nsIFrame* NS_NewSVGPatternFrame(nsIPresShell*   aPresShell,
                                nsStyleContext* aContext)
{
  return new (aPresShell) nsSVGPatternFrame(aContext);
}