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 { DrawPropertiesDrawProperties18 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 layer_or_descendant_has_input_handler(false), 33 has_child_with_a_scroll_parent(false), 34 sorted_for_recursion(false), 35 index_of_first_descendants_addition(0), 36 num_descendants_added(0), 37 index_of_first_render_surface_layer_list_addition(0), 38 num_render_surfaces_added(0), 39 last_drawn_render_surface_layer_list_id(0), 40 ideal_contents_scale(0.f), 41 maximum_animation_contents_scale(0.f), 42 page_scale_factor(0.f), 43 device_scale_factor(0.f) {} 44 45 // Transforms objects from content space to target surface space, where 46 // this layer would be drawn. 47 gfx::Transform target_space_transform; 48 49 // Transforms objects from content space to screen space (viewport space). 50 gfx::Transform screen_space_transform; 51 52 // DrawProperties::opacity may be different than LayerType::opacity, 53 // particularly in the case when a RenderSurface re-parents the layer's 54 // opacity, or when opacity is compounded by the hierarchy. 55 float opacity; 56 57 // xxx_is_animating flags are used to indicate whether the DrawProperties 58 // are actually meaningful on the main thread. When the properties are 59 // animating, the main thread may not have the same values that are used 60 // to draw. 61 bool opacity_is_animating; 62 bool screen_space_opacity_is_animating; 63 bool target_space_transform_is_animating; 64 bool screen_space_transform_is_animating; 65 66 // True if the layer can use LCD text. 67 bool can_use_lcd_text; 68 69 // True if the layer needs to be clipped by clip_rect. 70 bool is_clipped; 71 72 // The layer whose coordinate space this layer draws into. This can be 73 // either the same layer (draw_properties_.render_target == this) or an 74 // ancestor of this layer. 75 LayerType* render_target; 76 77 // The surface that this layer and its subtree would contribute to. 78 scoped_ptr<typename LayerType::RenderSurfaceType> render_surface; 79 80 // This rect is in the layer's content space. 81 gfx::Rect visible_content_rect; 82 83 // In target surface space, the rect that encloses the clipped, drawable 84 // content of the layer. 85 gfx::Rect drawable_content_rect; 86 87 // In target surface space, the original rect that clipped this layer. This 88 // value is used to avoid unnecessarily changing GL scissor state. 89 gfx::Rect clip_rect; 90 91 // The scale used to move between layer space and content space, and bounds 92 // of the space. One is always a function of the other, but which one 93 // depends on the layer type. For picture layers, this is an ideal scale, 94 // and not always the one used. 95 float contents_scale_x; 96 float contents_scale_y; 97 gfx::Size content_bounds; 98 99 // Does not include this layer itself, only its children and descendants. 100 int num_descendants_that_draw_content; 101 102 // Number of descendants with a clip parent that is our ancestor. NB - this 103 // does not include our clip children because they are clipped by us. 104 int num_unclipped_descendants; 105 106 // If true, the layer or some layer in its sub-tree has a CopyOutputRequest 107 // present on it. 108 bool layer_or_descendant_has_copy_request; 109 110 // If true, the layer or one of its descendants has a wheel or touch handler. 111 bool layer_or_descendant_has_input_handler; 112 113 // This is true if the layer has any direct child that has a scroll parent. 114 // This layer will not be the scroll parent in this case. This information 115 // lets us avoid work in CalculateDrawPropertiesInternal -- if none of our 116 // children have scroll parents, we will not need to recur out of order. 117 bool has_child_with_a_scroll_parent; 118 119 // This is true if the order (wrt to its siblings in the tree) in which the 120 // layer will be visited while computing draw properties has been determined. 121 bool sorted_for_recursion; 122 123 // If this layer is visited out of order, its contribution to the descendant 124 // and render surface layer lists will be put aside in a temporary list. 125 // These values will allow for an efficient reordering of these additions. 126 size_t index_of_first_descendants_addition; 127 size_t num_descendants_added; 128 size_t index_of_first_render_surface_layer_list_addition; 129 size_t num_render_surfaces_added; 130 131 // Each time we generate a new render surface layer list, an ID is used to 132 // identify it. |last_drawn_render_surface_layer_list_id| is set to the ID 133 // that marked the render surface layer list generation which last updated 134 // these draw properties and determined that this layer will draw itself. 135 // If these draw properties are not a part of the render surface layer list, 136 // or the layer doesn't contribute anything, then this ID will be either out 137 // of date or 0. 138 int last_drawn_render_surface_layer_list_id; 139 140 // The scale at which content for the layer should be rastered in order to be 141 // perfectly crisp. 142 float ideal_contents_scale; 143 144 // The maximum scale during the layers current animation at which content 145 // should be rastered at to be crisp. 146 float maximum_animation_contents_scale; 147 148 // The page scale factor that is applied to the layer. Since some layers may 149 // have page scale applied and others not, this may differ between layers. 150 float page_scale_factor; 151 152 // The device scale factor that is applied to the layer. 153 float device_scale_factor; 154 }; 155 156 } // namespace cc 157 158 #endif // CC_LAYERS_DRAW_PROPERTIES_H_ 159