cc/quads/draw_quad.h

   1 // Copyright 2012 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 CC_QUADS_DRAW_QUAD_H_
   6 #define CC_QUADS_DRAW_QUAD_H_
   7
   8 #include "base/callback.h"
   9 #include "cc/base/cc_export.h"
  10 #include "cc/base/resource_id.h"
  11 #include "cc/quads/shared_quad_state.h"
  12
  13 namespace base {
  14 namespace trace_event {
  15 class TracedValue;
  16 }
  17 class Value;
  18 class DictionaryValue;
  19 }
  20
  21 namespace cc {
  22
  23 // DrawQuad is a bag of data used for drawing a quad. Because different
  24 // materials need different bits of per-quad data to render, classes that derive
  25 // from DrawQuad store additional data in their derived instance. The Material
  26 // enum is used to "safely" downcast to the derived class.
  27 // Note: quads contain rects and sizes, which live in different spaces. There is
  28 // the "content space", which is the arbitrary space in which the quad's
  29 // geometry is defined (generally related to the layer that produced the quad,
  30 // e.g. the geometry space for PictureLayerImpls or the layer's coordinate space
  31 // for most other layers). There is also the "target space", which is the space,
  32 // in "physical" pixels, of the render target where the quads is drawn. The
  33 // quad's transform maps the content space to the target space.
  34 class CC_EXPORT DrawQuad {
  35  public:
  36   enum Material {
  37     INVALID,
  38     DEBUG_BORDER,
  39     IO_SURFACE_CONTENT,
  40     PICTURE_CONTENT,
  41     RENDER_PASS,
  42     SOLID_COLOR,
  43     STREAM_VIDEO_CONTENT,
  44     SURFACE_CONTENT,
  45     TEXTURE_CONTENT,
  46     TILED_CONTENT,
  47     YUV_VIDEO_CONTENT,
  48     MATERIAL_LAST = YUV_VIDEO_CONTENT
  49   };
  50
  51   virtual ~DrawQuad();
  52
  53   Material material;
  54
  55   // This rect, after applying the quad_transform(), gives the geometry that
  56   // this quad should draw to. This rect lives in content space.
  57   gfx::Rect rect;
  58
  59   // This specifies the region of the quad that is opaque. This rect lives in
  60   // content space.
  61   gfx::Rect opaque_rect;
  62
  63   // Allows changing the rect that gets drawn to make it smaller. This value
  64   // should be clipped to |rect|. This rect lives in content space.
  65   gfx::Rect visible_rect;
  66
  67   // By default blending is used when some part of the quad is not opaque.
  68   // With this setting, it is possible to force blending on regardless of the
  69   // opaque area.
  70   bool needs_blending;
  71
  72   // Stores state common to a large bundle of quads; kept separate for memory
  73   // efficiency. There is special treatment to reconstruct these pointers
  74   // during serialization.
  75   const SharedQuadState* shared_quad_state;
  76
  77   bool IsDebugQuad() const { return material == DEBUG_BORDER; }
  78
  79   bool ShouldDrawWithBlending() const {
  80     if (needs_blending || shared_quad_state->opacity < 1.0f)
  81       return true;
  82     if (visible_rect.IsEmpty())
  83       return false;
  84     return !opaque_rect.Contains(visible_rect);
  85   }
  86
  87   // Is the left edge of this tile aligned with the originating layer's
  88   // left edge?
  89   bool IsLeftEdge() const { return !rect.x(); }
  90
  91   // Is the top edge of this tile aligned with the originating layer's
  92   // top edge?
  93   bool IsTopEdge() const { return !rect.y(); }
  94
  95   // Is the right edge of this tile aligned with the originating layer's
  96   // right edge?
  97   bool IsRightEdge() const {
  98     return rect.right() == shared_quad_state->quad_layer_bounds.width();
  99   }
 100
 101   // Is the bottom edge of this tile aligned with the originating layer's
 102   // bottom edge?
 103   bool IsBottomEdge() const {
 104     return rect.bottom() == shared_quad_state->quad_layer_bounds.height();
 105   }
 106
 107   // Is any edge of this tile aligned with the originating layer's
 108   // corresponding edge?
 109   bool IsEdge() const {
 110     return IsLeftEdge() || IsTopEdge() || IsRightEdge() || IsBottomEdge();
 111   }
 112
 113   void AsValueInto(base::trace_event::TracedValue* value) const;
 114
 115   struct CC_EXPORT Resources {
 116     enum : size_t { kMaxResourceIdCount = 4 };
 117     Resources();
 118
 119     ResourceId* begin() { return ids; }
 120     ResourceId* end() {
 121       DCHECK_LE(count, kMaxResourceIdCount);
 122       return ids + count;
 123     }
 124
 125     size_t count;
 126     ResourceId ids[kMaxResourceIdCount];
 127   };
 128
 129   Resources resources;
 130
 131  protected:
 132   DrawQuad();
 133
 134   void SetAll(const SharedQuadState* shared_quad_state,
 135               Material material,
 136               const gfx::Rect& rect,
 137               const gfx::Rect& opaque_rect,
 138               const gfx::Rect& visible_rect,
 139               bool needs_blending);
 140   virtual void ExtendValue(base::trace_event::TracedValue* value) const = 0;
 141 };
 142
 143 }  // namespace cc
 144
 145 #endif  // CC_QUADS_DRAW_QUAD_H_