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_LAYERS_DRAW_PROPERTIES_H_ 6 #define CC_LAYERS_DRAW_PROPERTIES_H_ 7 8 #include "base/memory/scoped_ptr.h" 9 #include "ui/gfx/rect.h" 10 #include "ui/gfx/transform.h" 11 12 namespace cc { 13 14 // Container for properties that layers need to compute before they can be 15 // drawn. 16 template <typename LayerType> 17 struct CC_EXPORT DrawProperties { 18 DrawProperties() 19 : opacity(0.f), 20 opacity_is_animating(false), 21 screen_space_opacity_is_animating(false), 22 target_space_transform_is_animating(false), 23 screen_space_transform_is_animating(false), 24 can_use_lcd_text(false), 25 is_clipped(false), 26 render_target(NULL), 27 contents_scale_x(1.f), 28 contents_scale_y(1.f), 29 num_descendants_that_draw_content(0), 30 num_unclipped_descendants(0), 31 layer_or_descendant_has_copy_request(false), 32 has_child_with_a_scroll_parent(false), 33 sorted_for_recursion(false), 34 index_of_first_descendants_addition(0), 35 num_descendants_added(0), 36 index_of_first_render_surface_layer_list_addition(0), 37 num_render_surfaces_added(0) {} 38 39 // Transforms objects from content space to target surface space, where 40 // this layer would be drawn. 41 gfx::Transform target_space_transform; 42 43 // Transforms objects from content space to screen space (viewport space). 44 gfx::Transform screen_space_transform; 45 46 // DrawProperties::opacity may be different than LayerType::opacity, 47 // particularly in the case when a RenderSurface re-parents the layer's 48 // opacity, or when opacity is compounded by the hierarchy. 49 float opacity; 50 51 // xxx_is_animating flags are used to indicate whether the DrawProperties 52 // are actually meaningful on the main thread. When the properties are 53 // animating, the main thread may not have the same values that are used 54 // to draw. 55 bool opacity_is_animating; 56 bool screen_space_opacity_is_animating; 57 bool target_space_transform_is_animating; 58 bool screen_space_transform_is_animating; 59 60 // True if the layer can use LCD text. 61 bool can_use_lcd_text; 62 63 // True if the layer needs to be clipped by clip_rect. 64 bool is_clipped; 65 66 // The layer whose coordinate space this layer draws into. This can be 67 // either the same layer (draw_properties_.render_target == this) or an 68 // ancestor of this layer. 69 LayerType* render_target; 70 71 // The surface that this layer and its subtree would contribute to. 72 scoped_ptr<typename LayerType::RenderSurfaceType> render_surface; 73 74 // This rect is in the layer's content space. 75 gfx::Rect visible_content_rect; 76 77 // In target surface space, the rect that encloses the clipped, drawable 78 // content of the layer. 79 gfx::Rect drawable_content_rect; 80 81 // In target surface space, the original rect that clipped this layer. This 82 // value is used to avoid unnecessarily changing GL scissor state. 83 gfx::Rect clip_rect; 84 85 // The scale used to move between layer space and content space, and bounds 86 // of the space. One is always a function of the other, but which one 87 // depends on the layer type. For picture layers, this is an ideal scale, 88 // and not always the one used. 89 float contents_scale_x; 90 float contents_scale_y; 91 gfx::Size content_bounds; 92 93 // Does not include this layer itself, only its children and descendants. 94 int num_descendants_that_draw_content; 95 96 // Number of descendants with a clip parent that is our ancestor. NB - this 97 // does not include our clip children because they are clipped by us. 98 int num_unclipped_descendants; 99 100 // If true, the layer or some layer in its sub-tree has a CopyOutputRequest 101 // present on it. 102 bool layer_or_descendant_has_copy_request; 103 104 // This is true if the layer has any direct child that has a scroll parent. 105 // This layer will not be the scroll parent in this case. This information 106 // lets us avoid work in CalculateDrawPropertiesInternal -- if none of our 107 // children have scroll parents, we will not need to recur out of order. 108 bool has_child_with_a_scroll_parent; 109 110 // This is true if the order (wrt to its siblings in the tree) in which the 111 // layer will be visited while computing draw properties has been determined. 112 bool sorted_for_recursion; 113 114 // If this layer is visited out of order, its contribution to the descendant 115 // and render surface layer lists will be put aside in a temporary list. 116 // These values will allow for an efficient reordering of these additions. 117 size_t index_of_first_descendants_addition; 118 size_t num_descendants_added; 119 size_t index_of_first_render_surface_layer_list_addition; 120 size_t num_render_surfaces_added; 121 }; 122 123 } // namespace cc 124 125 #endif // CC_LAYERS_DRAW_PROPERTIES_H_ 126