src/third_party/WebKit/Source/platform/graphics/CompositingReasons.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CompositingReasons_h
   6 #define CompositingReasons_h
   7
   8 #include "platform/PlatformExport.h"
   9 #include "wtf/MathExtras.h"
  10 #include <stdint.h>
  11
  12 namespace blink {
  13
  14 const uint64_t CompositingReasonNone                                     = 0;
  15 const uint64_t CompositingReasonAll                                      = ~static_cast<uint64_t>(0);
  16
  17 // Intrinsic reasons that can be known right away by the layer
  18 const uint64_t CompositingReason3DTransform                              = UINT64_C(1) << 0;
  19 const uint64_t CompositingReasonVideo                                    = UINT64_C(1) << 1;
  20 const uint64_t CompositingReasonCanvas                                   = UINT64_C(1) << 2;
  21 const uint64_t CompositingReasonPlugin                                   = UINT64_C(1) << 3;
  22 const uint64_t CompositingReasonIFrame                                   = UINT64_C(1) << 4;
  23 const uint64_t CompositingReasonBackfaceVisibilityHidden                 = UINT64_C(1) << 5;
  24 const uint64_t CompositingReasonActiveAnimation                          = UINT64_C(1) << 6;
  25 const uint64_t CompositingReasonTransitionProperty                       = UINT64_C(1) << 7;
  26 const uint64_t CompositingReasonPositionFixed                            = UINT64_C(1) << 8;
  27 const uint64_t CompositingReasonOverflowScrollingTouch                   = UINT64_C(1) << 9;
  28 const uint64_t CompositingReasonOverflowScrollingParent                  = UINT64_C(1) << 10;
  29 const uint64_t CompositingReasonOutOfFlowClipping                        = UINT64_C(1) << 11;
  30 const uint64_t CompositingReasonVideoOverlay                             = UINT64_C(1) << 12;
  31 const uint64_t CompositingReasonWillChangeCompositingHint                = UINT64_C(1) << 13;
  32
  33 // Overlap reasons that require knowing what's behind you in paint-order before knowing the answer
  34 const uint64_t CompositingReasonAssumedOverlap                           = UINT64_C(1) << 14;
  35 const uint64_t CompositingReasonOverlap                                  = UINT64_C(1) << 15;
  36 const uint64_t CompositingReasonNegativeZIndexChildren                   = UINT64_C(1) << 16;
  37 const uint64_t CompositingReasonScrollsWithRespectToSquashingLayer       = UINT64_C(1) << 17;
  38 const uint64_t CompositingReasonSquashingSparsityExceeded                = UINT64_C(1) << 18;
  39 const uint64_t CompositingReasonSquashingClippingContainerMismatch       = UINT64_C(1) << 19;
  40 const uint64_t CompositingReasonSquashingOpacityAncestorMismatch         = UINT64_C(1) << 20;
  41 const uint64_t CompositingReasonSquashingTransformAncestorMismatch       = UINT64_C(1) << 21;
  42 const uint64_t CompositingReasonSquashingFilterAncestorMismatch          = UINT64_C(1) << 22;
  43 const uint64_t CompositingReasonSquashingWouldBreakPaintOrder            = UINT64_C(1) << 23;
  44 const uint64_t CompositingReasonSquashingVideoIsDisallowed               = UINT64_C(1) << 24;
  45 const uint64_t CompositingReasonSquashedLayerClipsCompositingDescendants = UINT64_C(1) << 25;
  46 const uint64_t CompositingReasonSquashingRenderPartIsDisallowed          = UINT64_C(1) << 26;
  47 const uint64_t CompositingReasonSquashingReflectionIsDisallowed          = UINT64_C(1) << 27;
  48
  49 // Subtree reasons that require knowing what the status of your subtree is before knowing the answer
  50 const uint64_t CompositingReasonTransformWithCompositedDescendants       = UINT64_C(1) << 28;
  51 const uint64_t CompositingReasonOpacityWithCompositedDescendants         = UINT64_C(1) << 29;
  52 const uint64_t CompositingReasonMaskWithCompositedDescendants            = UINT64_C(1) << 30;
  53 const uint64_t CompositingReasonReflectionWithCompositedDescendants      = UINT64_C(1) << 31;
  54 const uint64_t CompositingReasonFilterWithCompositedDescendants          = UINT64_C(1) << 32;
  55 const uint64_t CompositingReasonBlendingWithCompositedDescendants        = UINT64_C(1) << 33;
  56 const uint64_t CompositingReasonClipsCompositingDescendants              = UINT64_C(1) << 34;
  57 const uint64_t CompositingReasonPerspectiveWith3DDescendants             = UINT64_C(1) << 35;
  58 const uint64_t CompositingReasonPreserve3DWith3DDescendants              = UINT64_C(1) << 36;
  59 const uint64_t CompositingReasonReflectionOfCompositedParent             = UINT64_C(1) << 37;
  60 const uint64_t CompositingReasonIsolateCompositedDescendants             = UINT64_C(1) << 38;
  61
  62 // The root layer is a special case that may be forced to be a layer, but also it needs to be
  63 // a layer if anything else in the subtree is composited.
  64 const uint64_t CompositingReasonRoot                                     = UINT64_C(1) << 39;
  65
  66 // CompositedLayerMapping internal hierarchy reasons
  67 const uint64_t CompositingReasonLayerForAncestorClip                     = UINT64_C(1) << 40;
  68 const uint64_t CompositingReasonLayerForDescendantClip                   = UINT64_C(1) << 41;
  69 const uint64_t CompositingReasonLayerForPerspective                      = UINT64_C(1) << 42;
  70 const uint64_t CompositingReasonLayerForHorizontalScrollbar              = UINT64_C(1) << 43;
  71 const uint64_t CompositingReasonLayerForVerticalScrollbar                = UINT64_C(1) << 44;
  72 const uint64_t CompositingReasonLayerForOverflowControlsHost             = UINT64_C(1) << 45;
  73 const uint64_t CompositingReasonLayerForScrollCorner                     = UINT64_C(1) << 46;
  74 const uint64_t CompositingReasonLayerForScrollingContents                = UINT64_C(1) << 47;
  75 const uint64_t CompositingReasonLayerForScrollingContainer               = UINT64_C(1) << 48;
  76 const uint64_t CompositingReasonLayerForSquashingContents                = UINT64_C(1) << 49;
  77 const uint64_t CompositingReasonLayerForSquashingContainer               = UINT64_C(1) << 50;
  78 const uint64_t CompositingReasonLayerForForeground                       = UINT64_C(1) << 51;
  79 const uint64_t CompositingReasonLayerForBackground                       = UINT64_C(1) << 52;
  80 const uint64_t CompositingReasonLayerForMask                             = UINT64_C(1) << 53;
  81 const uint64_t CompositingReasonLayerForClippingMask                     = UINT64_C(1) << 54;
  82 const uint64_t CompositingReasonLayerForScrollingBlockSelection          = UINT64_C(1) << 55;
  83
  84 // Composited elements with inline transforms trigger assumed overlap so that
  85 // we can update their transforms quickly.
  86 const uint64_t CompositingReasonInlineTransform                          = UINT64_C(1) << 56;
  87
  88 // Various combinations of compositing reasons are defined here also, for more intutive and faster bitwise logic.
  89 const uint64_t CompositingReasonComboAllDirectReasons =
  90     CompositingReason3DTransform
  91     | CompositingReasonVideo
  92     | CompositingReasonCanvas
  93     | CompositingReasonPlugin
  94     | CompositingReasonIFrame
  95     | CompositingReasonBackfaceVisibilityHidden
  96     | CompositingReasonActiveAnimation
  97     | CompositingReasonTransitionProperty
  98     | CompositingReasonPositionFixed
  99     | CompositingReasonOverflowScrollingTouch
 100     | CompositingReasonOverflowScrollingParent
 101     | CompositingReasonOutOfFlowClipping
 102     | CompositingReasonVideoOverlay
 103     | CompositingReasonWillChangeCompositingHint;
 104
 105 const uint64_t CompositingReasonComboAllDirectStyleDeterminedReasons =
 106     CompositingReason3DTransform
 107     | CompositingReasonBackfaceVisibilityHidden
 108     | CompositingReasonActiveAnimation
 109     | CompositingReasonTransitionProperty
 110     | CompositingReasonWillChangeCompositingHint;
 111
 112 const uint64_t CompositingReasonComboCompositedDescendants =
 113     CompositingReasonTransformWithCompositedDescendants
 114     | CompositingReasonIsolateCompositedDescendants
 115     | CompositingReasonOpacityWithCompositedDescendants
 116     | CompositingReasonMaskWithCompositedDescendants
 117     | CompositingReasonFilterWithCompositedDescendants
 118     | CompositingReasonBlendingWithCompositedDescendants
 119     | CompositingReasonReflectionWithCompositedDescendants
 120     | CompositingReasonClipsCompositingDescendants;
 121
 122 const uint64_t CompositingReasonCombo3DDescendants =
 123     CompositingReasonPreserve3DWith3DDescendants
 124     | CompositingReasonPerspectiveWith3DDescendants;
 125
 126 const uint64_t CompositingReasonComboAllStyleDeterminedReasons =
 127     CompositingReasonComboAllDirectStyleDeterminedReasons
 128     | CompositingReasonComboCompositedDescendants
 129     | CompositingReasonCombo3DDescendants
 130     | CompositingReasonInlineTransform;
 131
 132 const uint64_t CompositingReasonComboReasonsThatRequireOwnBacking =
 133     CompositingReasonComboAllDirectReasons
 134     | CompositingReasonOverlap
 135     | CompositingReasonAssumedOverlap
 136     | CompositingReasonNegativeZIndexChildren
 137     | CompositingReasonScrollsWithRespectToSquashingLayer
 138     | CompositingReasonSquashingSparsityExceeded
 139     | CompositingReasonSquashingClippingContainerMismatch
 140     | CompositingReasonSquashingOpacityAncestorMismatch
 141     | CompositingReasonSquashingTransformAncestorMismatch
 142     | CompositingReasonSquashingFilterAncestorMismatch
 143     | CompositingReasonSquashingWouldBreakPaintOrder
 144     | CompositingReasonSquashingVideoIsDisallowed
 145     | CompositingReasonSquashedLayerClipsCompositingDescendants
 146     | CompositingReasonSquashingRenderPartIsDisallowed
 147     | CompositingReasonSquashingReflectionIsDisallowed
 148     | CompositingReasonTransformWithCompositedDescendants
 149     | CompositingReasonOpacityWithCompositedDescendants
 150     | CompositingReasonMaskWithCompositedDescendants
 151     | CompositingReasonFilterWithCompositedDescendants
 152     | CompositingReasonBlendingWithCompositedDescendants
 153     | CompositingReasonIsolateCompositedDescendants
 154     | CompositingReasonPreserve3DWith3DDescendants; // preserve-3d has to create backing store to ensure that 3d-transformed elements intersect.
 155
 156 const uint64_t CompositingReasonComboSquashableReasons =
 157     CompositingReasonOverlap
 158     | CompositingReasonAssumedOverlap
 159     | CompositingReasonOverflowScrollingParent;
 160
 161 typedef uint64_t CompositingReasons;
 162
 163 // Any reasons other than overlap or assumed overlap will require the layer to be separately compositing.
 164 inline bool requiresCompositing(CompositingReasons reasons)
 165 {
 166     return reasons & ~CompositingReasonComboSquashableReasons;
 167 }
 168
 169 // If the layer has overlap or assumed overlap, but no other reasons, then it should be squashed.
 170 inline bool requiresSquashing(CompositingReasons reasons)
 171 {
 172     return !requiresCompositing(reasons) && (reasons & CompositingReasonComboSquashableReasons);
 173 }
 174
 175 struct CompositingReasonStringMap {
 176     CompositingReasons reason;
 177     const char* shortName;
 178     const char* description;
 179 };
 180
 181 PLATFORM_EXPORT extern const CompositingReasonStringMap kCompositingReasonStringMap[];
 182 PLATFORM_EXPORT extern size_t kNumberOfCompositingReasons;
 183
 184 } // namespace blink
 185
 186 #endif // CompositingReasons_h