Implement cc::SharedQuadState StructTraits

cc/ipc/shared_quad_state.mojom

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+module cc.mojom;
+
+import "ui/gfx/geometry/mojo/geometry.mojom";
+import "ui/gfx/mojo/transform.mojom";
+
+// TODO(fsamuel): This enum doesn't really belong here but SharedQuadState is
+// the only current consumer.
+enum SkXfermode {

[danakj, 2016/06/01 20:54:11]

Erm. Include skia's header? Why are we reproducing this enum? Skia folks will
surely not keep this up to date if it changes.

[Fady Samuel, 2016/06/01 21:02:49]

In the long term, enums should be represented only in mojoms. For now, we're
going to have to deal with this :(

[danakj, 2016/06/01 21:04:20]

Skia enums are going to be in mojoms? How are you going to deal with third_party
stuff?

+  kClear_Mode = 0,    //!< [0, 0]
+  kSrc_Mode,      //!< [Sa, Sc]
+  kDst_Mode,      //!< [Da, Dc]
+  kSrcOver_Mode,  //!< [Sa + Da - Sa*Da, Rc = Sc + (1 - Sa)*Dc]
+  kDstOver_Mode,  //!< [Sa + Da - Sa*Da, Rc = Dc + (1 - Da)*Sc]
+  kSrcIn_Mode,    //!< [Sa * Da, Sc * Da]
+  kDstIn_Mode,    //!< [Sa * Da, Sa * Dc]
+  kSrcOut_Mode,   //!< [Sa * (1 - Da), Sc * (1 - Da)]
+  kDstOut_Mode,   //!< [Da * (1 - Sa), Dc * (1 - Sa)]
+  kSrcATop_Mode,  //!< [Da, Sc * Da + (1 - Sa) * Dc]
+  kDstATop_Mode,  //!< [Sa, Sa * Dc + Sc * (1 - Da)]
+  kXor_Mode,      //!< [Sa + Da - 2 * Sa * Da, Sc * (1 - Da) + (1 - Sa) * Dc]
+  kPlus_Mode,     //!< [Sa + Da, Sc + Dc]
+  kModulate_Mode, // multiplies all components (= alpha and color)
+
+  // Following blend modes are defined in the CSS Compositing standard:
+  // https://dvcs.w3.org/hg/FXTF/rawfile/tip/compositing/index.html#blending
+  kScreen_Mode,
+  kLastCoeffMode = kScreen_Mode,
+
+  kOverlay_Mode,
+  kDarken_Mode,
+  kLighten_Mode,
+  kColorDodge_Mode,
+  kColorBurn_Mode,
+  kHardLight_Mode,
+  kSoftLight_Mode,
+  kDifference_Mode,
+  kExclusion_Mode,
+  kMultiply_Mode,
+  kLastSeparableMode = kMultiply_Mode,
+
+  kHue_Mode,
+  kSaturation_Mode,
+  kColor_Mode,
+  kLuminosity_Mode,
+  kLastMode = kLuminosity_Mode
+};
+
+
+struct SharedQuadState {
+  // gfx.mojom.Transforms quad rects into the target content space.
+  gfx.mojom.Transform quad_to_target_transform;
+
+  // The size of the quads' originating layer in the space of the quad rects.
+  gfx.mojom.Size quad_layer_bounds;
+
+  // The size of the visible area in the quads' originating layer, in the space
+  // of the quad rects.
+  gfx.mojom.Rect visible_quad_layer_rect;
+
+  // This rect lives in the target content space.
+  gfx.mojom.Rect clip_rect;
+
+  bool is_clipped;
+  float opacity;
+  SkXfermode blend_mode;
+  int32 sorting_context_id;
+};
+