summaryrefslogtreecommitdiffstats
path: root/gfx/layers/composite/TiledContentHost.cpp
blob: 7458c74971015e3110f17b74689e80eddc188c36 (plain)
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
/* -*- Mode: C++; tab-width: 20; 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/. */

#include "TiledContentHost.h"
#include "gfxPrefs.h"                   // for gfxPrefs
#include "PaintedLayerComposite.h"      // for PaintedLayerComposite
#include "mozilla/gfx/BaseSize.h"       // for BaseSize
#include "mozilla/gfx/Matrix.h"         // for Matrix4x4
#include "mozilla/gfx/Point.h"          // for IntSize
#include "mozilla/layers/Compositor.h"  // for Compositor
//#include "mozilla/layers/CompositorBridgeParent.h"  // for CompositorBridgeParent
#include "mozilla/layers/Effects.h"     // for TexturedEffect, Effect, etc
#include "mozilla/layers/LayerMetricsWrapper.h" // for LayerMetricsWrapper
#include "mozilla/layers/TextureHostOGL.h"  // for TextureHostOGL
#include "nsAString.h"
#include "nsDebug.h"                    // for NS_WARNING
#include "nsPoint.h"                    // for IntPoint
#include "nsPrintfCString.h"            // for nsPrintfCString
#include "nsRect.h"                     // for IntRect
#include "mozilla/layers/TextureClient.h"

namespace mozilla {
using namespace gfx;
namespace layers {

class Layer;

float
TileHost::GetFadeInOpacity(float aOpacity)
{
  TimeStamp now = TimeStamp::Now();
  if (!gfxPrefs::LayerTileFadeInEnabled() ||
      mFadeStart.IsNull() ||
      now < mFadeStart)
  {
    return aOpacity;
  }

  float duration = gfxPrefs::LayerTileFadeInDuration();
  float elapsed = (now - mFadeStart).ToMilliseconds();
  if (elapsed > duration) {
    mFadeStart = TimeStamp();
    return aOpacity;
  }
  return aOpacity * (elapsed / duration);
}

TiledLayerBufferComposite::TiledLayerBufferComposite()
  : mFrameResolution()
{}

TiledLayerBufferComposite::~TiledLayerBufferComposite()
{
  Clear();
}

void
TiledLayerBufferComposite::SetCompositor(Compositor* aCompositor)
{
  MOZ_ASSERT(aCompositor);
  for (TileHost& tile : mRetainedTiles) {
    if (tile.IsPlaceholderTile()) continue;
    tile.mTextureHost->SetCompositor(aCompositor);
    if (tile.mTextureHostOnWhite) {
      tile.mTextureHostOnWhite->SetCompositor(aCompositor);
    }
  }
}

void
TiledLayerBufferComposite::AddAnimationInvalidation(nsIntRegion& aRegion)
{
  // We need to invalidate rects where we have a tile that is in the
  // process of fading in.
  for (size_t i = 0; i < mRetainedTiles.Length(); i++) {
    if (!mRetainedTiles[i].mFadeStart.IsNull()) {
      TileIntPoint position = mTiles.TilePosition(i);
      IntPoint offset = GetTileOffset(position);
      nsIntRegion tileRegion = IntRect(offset, GetScaledTileSize());
      aRegion.OrWith(tileRegion);
    }
  }
}

TiledContentHost::TiledContentHost(const TextureInfo& aTextureInfo)
  : ContentHost(aTextureInfo)
  , mTiledBuffer(TiledLayerBufferComposite())
  , mLowPrecisionTiledBuffer(TiledLayerBufferComposite())
{
  MOZ_COUNT_CTOR(TiledContentHost);
}

TiledContentHost::~TiledContentHost()
{
  MOZ_COUNT_DTOR(TiledContentHost);
}

already_AddRefed<TexturedEffect>
TiledContentHost::GenEffect(const gfx::SamplingFilter aSamplingFilter)
{
  // If we can use hwc for this TiledContentHost, it implies that we have exactly
  // one high precision tile. Please check TiledContentHost::GetRenderState() for
  // all condition.
  MOZ_ASSERT(mTiledBuffer.GetTileCount() == 1 && mLowPrecisionTiledBuffer.GetTileCount() == 0);
  MOZ_ASSERT(mTiledBuffer.GetTile(0).mTextureHost);

  TileHost& tile = mTiledBuffer.GetTile(0);
  if (!tile.mTextureHost->BindTextureSource(tile.mTextureSource)) {
    return nullptr;
  }

  return CreateTexturedEffect(tile.mTextureSource,
                              nullptr,
                              aSamplingFilter,
                              true,
                              tile.mTextureHost->GetRenderState());
}

void
TiledContentHost::Attach(Layer* aLayer,
                         Compositor* aCompositor,
                         AttachFlags aFlags /* = NO_FLAGS */)
{
  CompositableHost::Attach(aLayer, aCompositor, aFlags);
}

void
TiledContentHost::Detach(Layer* aLayer,
                         AttachFlags aFlags /* = NO_FLAGS */)
{
  if (!mKeepAttached || aLayer == mLayer || aFlags & FORCE_DETACH) {
    // Clear the TiledLayerBuffers, which will take care of releasing the
    // copy-on-write locks.
    mTiledBuffer.Clear();
    mLowPrecisionTiledBuffer.Clear();
  }
  CompositableHost::Detach(aLayer,aFlags);
}

bool
TiledContentHost::UseTiledLayerBuffer(ISurfaceAllocator* aAllocator,
                                      const SurfaceDescriptorTiles& aTiledDescriptor)
{
  if (aTiledDescriptor.resolution() < 1) {
    if (!mLowPrecisionTiledBuffer.UseTiles(aTiledDescriptor, mCompositor, aAllocator)) {
      return false;
    }
  } else {
    if (!mTiledBuffer.UseTiles(aTiledDescriptor, mCompositor, aAllocator)) {
      return false;
    }
  }
  return true;
}

void
UseTileTexture(CompositableTextureHostRef& aTexture,
               CompositableTextureSourceRef& aTextureSource,
               const IntRect& aUpdateRect,
               Compositor* aCompositor)
{
  MOZ_ASSERT(aTexture);
  if (!aTexture) {
    return;
  }

  if (aCompositor) {
    aTexture->SetCompositor(aCompositor);
  }

  if (!aUpdateRect.IsEmpty()) {
    // For !HasIntermediateBuffer() textures, this is likely a no-op.
    nsIntRegion region = aUpdateRect;
    aTexture->Updated(&region);
  }

  aTexture->PrepareTextureSource(aTextureSource);
}

class TextureSourceRecycler
{
public:
  explicit TextureSourceRecycler(nsTArray<TileHost>&& aTileSet)
    : mTiles(Move(aTileSet))
    , mFirstPossibility(0)
  {}

  // Attempts to recycle a texture source that is already bound to the
  // texture host for aTile.
  void RecycleTextureSourceForTile(TileHost& aTile) {
    for (size_t i = mFirstPossibility; i < mTiles.Length(); i++) {
      // Skip over existing tiles without a retained texture source
      // and make sure we don't iterate them in the future.
      if (!mTiles[i].mTextureSource) {
        if (i == mFirstPossibility) {
          mFirstPossibility++;
        }
        continue;
      }

      // If this tile matches, then copy across the retained texture source (if
      // any).
      if (aTile.mTextureHost == mTiles[i].mTextureHost) {
        aTile.mTextureSource = Move(mTiles[i].mTextureSource);
        if (aTile.mTextureHostOnWhite) {
          aTile.mTextureSourceOnWhite = Move(mTiles[i].mTextureSourceOnWhite);
        }
        break;
      }
    }
  }

  // Attempts to recycle any texture source to avoid needing to allocate
  // a new one.
  void RecycleTextureSource(TileHost& aTile) {
    for (size_t i = mFirstPossibility; i < mTiles.Length(); i++) {
      if (!mTiles[i].mTextureSource) {
        if (i == mFirstPossibility) {
          mFirstPossibility++;
        }
        continue;
      }

      if (mTiles[i].mTextureSource &&
          mTiles[i].mTextureHost->GetFormat() == aTile.mTextureHost->GetFormat()) {
        aTile.mTextureSource = Move(mTiles[i].mTextureSource);
        if (aTile.mTextureHostOnWhite) {
          aTile.mTextureSourceOnWhite = Move(mTiles[i].mTextureSourceOnWhite);
        }
        break;
      }
    }
  }

  void RecycleTileFading(TileHost& aTile) {
    for (size_t i = 0; i < mTiles.Length(); i++) {
      if (mTiles[i].mTextureHost == aTile.mTextureHost) {
        aTile.mFadeStart = mTiles[i].mFadeStart;
      }
    }
  }

protected:
  nsTArray<TileHost> mTiles;
  size_t mFirstPossibility;
};

bool
TiledLayerBufferComposite::UseTiles(const SurfaceDescriptorTiles& aTiles,
                                    Compositor* aCompositor,
                                    ISurfaceAllocator* aAllocator)
{
  if (mResolution != aTiles.resolution() ||
      aTiles.tileSize() != mTileSize) {
    Clear();
  }
  MOZ_ASSERT(aAllocator);
  MOZ_ASSERT(aCompositor);
  if (!aAllocator || !aCompositor) {
    return false;
  }

  if (aTiles.resolution() == 0 || IsNaN(aTiles.resolution())) {
    // There are divisions by mResolution so this protects the compositor process
    // against malicious content processes and fuzzing.
    return false;
  }

  TilesPlacement newTiles(aTiles.firstTileX(), aTiles.firstTileY(),
                          aTiles.retainedWidth(), aTiles.retainedHeight());

  const InfallibleTArray<TileDescriptor>& tileDescriptors = aTiles.tiles();

  TextureSourceRecycler oldRetainedTiles(Move(mRetainedTiles));
  mRetainedTiles.SetLength(tileDescriptors.Length());

  // Step 1, deserialize the incoming set of tiles into mRetainedTiles, and attempt
  // to recycle the TextureSource for any repeated tiles.
  //
  // Since we don't have any retained 'tile' object, we have to search for instances
  // of the same TextureHost in the old tile set. The cost of binding a TextureHost
  // to a TextureSource for gralloc (binding EGLImage to GL texture) can be really
  // high, so we avoid this whenever possible.
  for (size_t i = 0; i < tileDescriptors.Length(); i++) {
    const TileDescriptor& tileDesc = tileDescriptors[i];

    TileHost& tile = mRetainedTiles[i];

    if (tileDesc.type() != TileDescriptor::TTexturedTileDescriptor) {
      NS_WARNING_ASSERTION(
        tileDesc.type() == TileDescriptor::TPlaceholderTileDescriptor,
        "Unrecognised tile descriptor type");
      continue;
    }

    const TexturedTileDescriptor& texturedDesc = tileDesc.get_TexturedTileDescriptor();

    tile.mTextureHost = TextureHost::AsTextureHost(texturedDesc.textureParent());
    tile.mTextureHost->SetCompositor(aCompositor);
    tile.mTextureHost->DeserializeReadLock(texturedDesc.sharedLock(), aAllocator);

    if (texturedDesc.textureOnWhite().type() == MaybeTexture::TPTextureParent) {
      tile.mTextureHostOnWhite = TextureHost::AsTextureHost(
        texturedDesc.textureOnWhite().get_PTextureParent()
      );
      tile.mTextureHostOnWhite->DeserializeReadLock(
        texturedDesc.sharedLockOnWhite(), aAllocator
      );
    }

    tile.mTilePosition = newTiles.TilePosition(i);

    // If this same tile texture existed in the old tile set then this will move the texture
    // source into our new tile.
    oldRetainedTiles.RecycleTextureSourceForTile(tile);

    // If this tile is in the process of fading, we need to keep that going
    oldRetainedTiles.RecycleTileFading(tile);

    if (aTiles.isProgressive() &&
        texturedDesc.wasPlaceholder())
    {
      // This is a progressive paint, and the tile used to be a placeholder.
      // We need to begin fading it in (if enabled via layers.tiles.fade-in.enabled)
      tile.mFadeStart = TimeStamp::Now();

      aCompositor->CompositeUntil(tile.mFadeStart +
        TimeDuration::FromMilliseconds(gfxPrefs::LayerTileFadeInDuration()));
    }
  }

  // Step 2, attempt to recycle unused texture sources from the old tile set into new tiles.
  //
  // For gralloc, binding a new TextureHost to the existing TextureSource is the fastest way
  // to ensure that any implicit locking on the old gralloc image is released.
  for (TileHost& tile : mRetainedTiles) {
    if (!tile.mTextureHost || tile.mTextureSource) {
      continue;
    }
    oldRetainedTiles.RecycleTextureSource(tile);
  }

  // Step 3, handle the texture uploads, texture source binding and release the
  // copy-on-write locks for textures with an internal buffer.
  for (size_t i = 0; i < mRetainedTiles.Length(); i++) {
    TileHost& tile = mRetainedTiles[i];
    if (!tile.mTextureHost) {
      continue;
    }

    const TileDescriptor& tileDesc = tileDescriptors[i];
    const TexturedTileDescriptor& texturedDesc = tileDesc.get_TexturedTileDescriptor();

    UseTileTexture(tile.mTextureHost,
                   tile.mTextureSource,
                   texturedDesc.updateRect(),
                   aCompositor);

    if (tile.mTextureHostOnWhite) {
      UseTileTexture(tile.mTextureHostOnWhite,
                     tile.mTextureSourceOnWhite,
                     texturedDesc.updateRect(),
                     aCompositor);
    }
  }

  mTiles = newTiles;
  mTileSize = aTiles.tileSize();
  mTileOrigin = aTiles.tileOrigin();
  mValidRegion = aTiles.validRegion();
  mResolution = aTiles.resolution();
  mFrameResolution = CSSToParentLayerScale2D(aTiles.frameXResolution(),
                                             aTiles.frameYResolution());

  return true;
}

void
TiledLayerBufferComposite::Clear()
{
  mRetainedTiles.Clear();
  mTiles.mFirst = TileIntPoint();
  mTiles.mSize = TileIntSize();
  mValidRegion = nsIntRegion();
  mResolution = 1.0;
}

void
TiledContentHost::Composite(LayerComposite* aLayer,
                            EffectChain& aEffectChain,
                            float aOpacity,
                            const gfx::Matrix4x4& aTransform,
                            const gfx::SamplingFilter aSamplingFilter,
                            const gfx::IntRect& aClipRect,
                            const nsIntRegion* aVisibleRegion /* = nullptr */)
{
  MOZ_ASSERT(mCompositor);
  // Reduce the opacity of the low-precision buffer to make it a
  // little more subtle and less jarring. In particular, text
  // rendered at low-resolution and scaled tends to look pretty
  // heavy and this helps mitigate that. When we reduce the opacity
  // we also make sure to draw the background color behind the
  // reduced-opacity tile so that content underneath doesn't show
  // through.
  // However, in cases where the background is transparent, or the layer
  // already has some opacity, we want to skip this behaviour. Otherwise
  // we end up changing the expected overall transparency of the content,
  // and it just looks wrong.
  Color backgroundColor;
  if (aOpacity == 1.0f && gfxPrefs::LowPrecisionOpacity() < 1.0f) {
    // Background colors are only stored on scrollable layers. Grab
    // the one from the nearest scrollable ancestor layer.
    for (LayerMetricsWrapper ancestor(GetLayer(), LayerMetricsWrapper::StartAt::BOTTOM); ancestor; ancestor = ancestor.GetParent()) {
      if (ancestor.Metrics().IsScrollable()) {
        backgroundColor = ancestor.Metadata().GetBackgroundColor();
        break;
      }
    }
  }
  float lowPrecisionOpacityReduction =
        (aOpacity == 1.0f && backgroundColor.a == 1.0f)
        ? gfxPrefs::LowPrecisionOpacity() : 1.0f;

  nsIntRegion tmpRegion;
  const nsIntRegion* renderRegion = aVisibleRegion;
#ifndef MOZ_IGNORE_PAINT_WILL_RESAMPLE
  if (PaintWillResample()) {
    // If we're resampling, then the texture image will contain exactly the
    // entire visible region's bounds, and we should draw it all in one quad
    // to avoid unexpected aliasing.
    tmpRegion = aVisibleRegion->GetBounds();
    renderRegion = &tmpRegion;
  }
#endif

  // Render the low and high precision buffers.
  RenderLayerBuffer(mLowPrecisionTiledBuffer,
                    lowPrecisionOpacityReduction < 1.0f ? &backgroundColor : nullptr,
                    aEffectChain, lowPrecisionOpacityReduction * aOpacity,
                    aSamplingFilter, aClipRect, *renderRegion, aTransform);
  RenderLayerBuffer(mTiledBuffer, nullptr, aEffectChain, aOpacity, aSamplingFilter,
                    aClipRect, *renderRegion, aTransform);
}


void
TiledContentHost::RenderTile(TileHost& aTile,
                             EffectChain& aEffectChain,
                             float aOpacity,
                             const gfx::Matrix4x4& aTransform,
                             const gfx::SamplingFilter aSamplingFilter,
                             const gfx::IntRect& aClipRect,
                             const nsIntRegion& aScreenRegion,
                             const IntPoint& aTextureOffset,
                             const IntSize& aTextureBounds,
                             const gfx::Rect& aVisibleRect)
{
  MOZ_ASSERT(!aTile.IsPlaceholderTile());

  AutoLockTextureHost autoLock(aTile.mTextureHost);
  AutoLockTextureHost autoLockOnWhite(aTile.mTextureHostOnWhite);
  if (autoLock.Failed() ||
      autoLockOnWhite.Failed()) {
    NS_WARNING("Failed to lock tile");
    return;
  }

  if (!aTile.mTextureHost->BindTextureSource(aTile.mTextureSource)) {
    return;
  }

  if (aTile.mTextureHostOnWhite && !aTile.mTextureHostOnWhite->BindTextureSource(aTile.mTextureSourceOnWhite)) {
    return;
  }

  RefPtr<TexturedEffect> effect =
    CreateTexturedEffect(aTile.mTextureSource,
                         aTile.mTextureSourceOnWhite,
                         aSamplingFilter,
                         true,
                         aTile.mTextureHost->GetRenderState());
  if (!effect) {
    return;
  }

  float opacity = aTile.GetFadeInOpacity(aOpacity);
  aEffectChain.mPrimaryEffect = effect;

  for (auto iter = aScreenRegion.RectIter(); !iter.Done(); iter.Next()) {
    const IntRect& rect = iter.Get();
    Rect graphicsRect(rect.x, rect.y, rect.width, rect.height);
    Rect textureRect(rect.x - aTextureOffset.x, rect.y - aTextureOffset.y,
                     rect.width, rect.height);

    effect->mTextureCoords = Rect(textureRect.x / aTextureBounds.width,
                                  textureRect.y / aTextureBounds.height,
                                  textureRect.width / aTextureBounds.width,
                                  textureRect.height / aTextureBounds.height);
    mCompositor->DrawQuad(graphicsRect, aClipRect, aEffectChain, opacity, aTransform, aVisibleRect);
  }
  DiagnosticFlags flags = DiagnosticFlags::CONTENT | DiagnosticFlags::TILE;
  if (aTile.mTextureHostOnWhite) {
    flags |= DiagnosticFlags::COMPONENT_ALPHA;
  }
  mCompositor->DrawDiagnostics(flags,
                               aScreenRegion, aClipRect, aTransform, mFlashCounter);
}

void
TiledContentHost::RenderLayerBuffer(TiledLayerBufferComposite& aLayerBuffer,
                                    const Color* aBackgroundColor,
                                    EffectChain& aEffectChain,
                                    float aOpacity,
                                    const gfx::SamplingFilter aSamplingFilter,
                                    const gfx::IntRect& aClipRect,
                                    nsIntRegion aVisibleRegion,
                                    gfx::Matrix4x4 aTransform)
{
  if (!mCompositor) {
    NS_WARNING("Can't render tiled content host - no compositor");
    return;
  }
  float resolution = aLayerBuffer.GetResolution();
  gfx::Size layerScale(1, 1);

  // We assume that the current frame resolution is the one used in our high
  // precision layer buffer. Compensate for a changing frame resolution when
  // rendering the low precision buffer.
  if (aLayerBuffer.GetFrameResolution() != mTiledBuffer.GetFrameResolution()) {
    const CSSToParentLayerScale2D& layerResolution = aLayerBuffer.GetFrameResolution();
    const CSSToParentLayerScale2D& localResolution = mTiledBuffer.GetFrameResolution();
    layerScale.width = layerResolution.xScale / localResolution.xScale;
    layerScale.height = layerResolution.yScale / localResolution.yScale;
    aVisibleRegion.ScaleRoundOut(layerScale.width, layerScale.height);
  }

  // Make sure we don't render at low resolution where we have valid high
  // resolution content, to avoid overdraw and artifacts with semi-transparent
  // layers.
  nsIntRegion maskRegion;
  if (resolution != mTiledBuffer.GetResolution()) {
    maskRegion = mTiledBuffer.GetValidRegion();
    // XXX This should be ScaleRoundIn, but there is no such function on
    //     nsIntRegion.
    maskRegion.ScaleRoundOut(layerScale.width, layerScale.height);
  }

  // Make sure the resolution and difference in frame resolution are accounted
  // for in the layer transform.
  aTransform.PreScale(1/(resolution * layerScale.width),
                      1/(resolution * layerScale.height), 1);

  DiagnosticFlags componentAlphaDiagnostic = DiagnosticFlags::NO_DIAGNOSTIC;

  nsIntRegion compositeRegion = aLayerBuffer.GetValidRegion();
  compositeRegion.AndWith(aVisibleRegion);
  compositeRegion.SubOut(maskRegion);

  IntRect visibleRect = aVisibleRegion.GetBounds();

  if (compositeRegion.IsEmpty()) {
    return;
  }

  if (aBackgroundColor) {
    nsIntRegion backgroundRegion = compositeRegion;
    backgroundRegion.ScaleRoundOut(resolution, resolution);
    EffectChain effect;
    effect.mPrimaryEffect = new EffectSolidColor(*aBackgroundColor);
    for (auto iter = backgroundRegion.RectIter(); !iter.Done(); iter.Next()) {
      const IntRect& rect = iter.Get();
      Rect graphicsRect(rect.x, rect.y, rect.width, rect.height);
      mCompositor->DrawQuad(graphicsRect, aClipRect, effect, 1.0, aTransform);
    }
  }

  for (size_t i = 0; i < aLayerBuffer.GetTileCount(); ++i) {
    TileHost& tile = aLayerBuffer.GetTile(i);
    if (tile.IsPlaceholderTile()) {
      continue;
    }

    TileIntPoint tilePosition = aLayerBuffer.GetPlacement().TilePosition(i);
    // A sanity check that catches a lot of mistakes.
    MOZ_ASSERT(tilePosition.x == tile.mTilePosition.x && tilePosition.y == tile.mTilePosition.y);

    IntPoint tileOffset = aLayerBuffer.GetTileOffset(tilePosition);
    nsIntRegion tileDrawRegion = IntRect(tileOffset, aLayerBuffer.GetScaledTileSize());
    tileDrawRegion.AndWith(compositeRegion);

    if (tileDrawRegion.IsEmpty()) {
      continue;
    }

    tileDrawRegion.ScaleRoundOut(resolution, resolution);
    RenderTile(tile, aEffectChain, aOpacity,
               aTransform, aSamplingFilter, aClipRect, tileDrawRegion,
               tileOffset * resolution, aLayerBuffer.GetTileSize(),
               gfx::Rect(visibleRect.x, visibleRect.y,
                         visibleRect.width, visibleRect.height));
    if (tile.mTextureHostOnWhite) {
      componentAlphaDiagnostic = DiagnosticFlags::COMPONENT_ALPHA;
    }
  }

  gfx::Rect rect(visibleRect.x, visibleRect.y,
                 visibleRect.width, visibleRect.height);
  GetCompositor()->DrawDiagnostics(DiagnosticFlags::CONTENT | componentAlphaDiagnostic,
                                   rect, aClipRect, aTransform, mFlashCounter);
}

void
TiledContentHost::PrintInfo(std::stringstream& aStream, const char* aPrefix)
{
  aStream << aPrefix;
  aStream << nsPrintfCString("TiledContentHost (0x%p)", this).get();

  if (gfxPrefs::LayersDumpTexture() || profiler_feature_active("layersdump")) {
    nsAutoCString pfx(aPrefix);
    pfx += "  ";

    Dump(aStream, pfx.get(), false);
  }
}

void
TiledContentHost::Dump(std::stringstream& aStream,
                       const char* aPrefix,
                       bool aDumpHtml)
{
  mTiledBuffer.Dump(aStream, aPrefix, aDumpHtml,
      TextureDumpMode::DoNotCompress /* compression not supported on host side */);
}

void
TiledContentHost::AddAnimationInvalidation(nsIntRegion& aRegion)
{
  return mTiledBuffer.AddAnimationInvalidation(aRegion);
}


} // namespace layers
} // namespace mozilla