1 // Copyright 2013 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 "wtf/MathExtras.h" 9 10 namespace WebCore { 11 12 const uint64_t CompositingReasonNone = 0; 13 14 // Intrinsic reasons that can be known right away by the layer 15 const uint64_t CompositingReason3DTransform = UINT64_C(1) << 0; 16 const uint64_t CompositingReasonVideo = UINT64_C(1) << 1; 17 const uint64_t CompositingReasonCanvas = UINT64_C(1) << 2; 18 const uint64_t CompositingReasonPlugin = UINT64_C(1) << 3; 19 const uint64_t CompositingReasonIFrame = UINT64_C(1) << 4; 20 const uint64_t CompositingReasonBackfaceVisibilityHidden = UINT64_C(1) << 5; 21 const uint64_t CompositingReasonAnimation = UINT64_C(1) << 6; 22 const uint64_t CompositingReasonFilters = UINT64_C(1) << 7; 23 const uint64_t CompositingReasonPositionFixed = UINT64_C(1) << 8; 24 const uint64_t CompositingReasonPositionSticky = UINT64_C(1) << 9; 25 const uint64_t CompositingReasonOverflowScrollingTouch = UINT64_C(1) << 10; 26 const uint64_t CompositingReasonBlending = UINT64_C(1) << 11; 27 28 // Overlap reasons that require knowing what's behind you in paint-order before knowing the answer 29 const uint64_t CompositingReasonAssumedOverlap = UINT64_C(1) << 12; 30 const uint64_t CompositingReasonOverlap = UINT64_C(1) << 13; 31 const uint64_t CompositingReasonNegativeZIndexChildren = UINT64_C(1) << 14; 32 33 // Subtree reasons that require knowing what the status of your subtree is before knowing the answer 34 const uint64_t CompositingReasonTransformWithCompositedDescendants = UINT64_C(1) << 15; 35 const uint64_t CompositingReasonOpacityWithCompositedDescendants = UINT64_C(1) << 16; 36 const uint64_t CompositingReasonMaskWithCompositedDescendants = UINT64_C(1) << 17; 37 const uint64_t CompositingReasonReflectionWithCompositedDescendants = UINT64_C(1) << 18; 38 const uint64_t CompositingReasonFilterWithCompositedDescendants = UINT64_C(1) << 19; 39 const uint64_t CompositingReasonBlendingWithCompositedDescendants = UINT64_C(1) << 20; 40 const uint64_t CompositingReasonClipsCompositingDescendants = UINT64_C(1) << 21; 41 const uint64_t CompositingReasonPerspective = UINT64_C(1) << 22; 42 const uint64_t CompositingReasonPreserve3D = UINT64_C(1) << 23; 43 const uint64_t CompositingReasonReflectionOfCompositedParent = UINT64_C(1) << 24; 44 45 // The root layer is a special case that may be forced to be a layer, but also it needs to be 46 // a layer if anything else in the subtree is composited. 47 const uint64_t CompositingReasonRoot = UINT64_C(1) << 25; 48 49 // RenderLayerBacking internal hierarchy reasons 50 const uint64_t CompositingReasonLayerForClip = UINT64_C(1) << 26; 51 const uint64_t CompositingReasonLayerForScrollbar = UINT64_C(1) << 27; 52 const uint64_t CompositingReasonLayerForScrollingContainer = UINT64_C(1) << 28; 53 const uint64_t CompositingReasonLayerForForeground = UINT64_C(1) << 29; 54 const uint64_t CompositingReasonLayerForBackground = UINT64_C(1) << 30; 55 const uint64_t CompositingReasonLayerForMask = UINT64_C(1) << 31; 56 57 // FIXME: the following compositing reasons need to be re-organized to fit with categories 58 // used in all the other reasons above. 59 const uint64_t CompositingReasonLayerForVideoOverlay = UINT64_C(1) << 32; 60 61 // Note: if you add more reasons here, you will need to update WebCompositingReasons as well. 62 typedef uint64_t CompositingReasons; 63 64 65 } // namespace WebCore 66 67 #endif // CompositingReasons_h 68