1 // Copyright (c) 2010 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.
5 #ifndef PDF_PAINT_AGGREGATOR_H_
6 #define PDF_PAINT_AGGREGATOR_H_
10 #include "ppapi/cpp/image_data.h"
11 #include "ppapi/cpp/rect.h"
13 // This class is responsible for aggregating multiple invalidation and scroll
14 // commands to produce a scroll and repaint sequence. You can use this manually
15 // to track your updates, but most applications will use the PaintManager to
16 // additionally handle the necessary callbacks on top of the PaintAggregator
19 // See http://code.google.com/p/ppapi/wiki/2DPaintingModel
20 class PaintAggregator {
22 // Stores information about a rectangle that has finished painting. The
23 // PaintManager will paint it only when everything else on the screen is also
28 pp::ImageData image_data;
33 PaintUpdate(const PaintUpdate& that);
36 // True if there is a scroll applied. This indicates that the scroll delta
37 // and scroll_rect are nonzero (just as a convenience).
40 // The amount to scroll by. Either the X or Y may be nonzero to indicate a
41 // scroll in that direction, but there will never be a scroll in both
42 // directions at the same time (this will be converted to a paint of the
45 // If there is no scroll, this will be (0, 0).
46 pp::Point scroll_delta;
48 // The rectangle that should be scrolled by the scroll_delta. If there is no
49 // scroll, this will be (0, 0, 0, 0). We only track one scroll command at
50 // once. If there are multiple ones, they will be converted to invalidates.
53 // A list of all the individual dirty rectangles. This is an aggregated list
54 // of all invalidate calls. Different rectangles may be unified to produce a
55 // minimal list with no overlap that is more efficient to paint. This list
56 // also contains the region exposed by any scroll command.
57 std::vector<pp::Rect> paint_rects;
62 // There is a PendingUpdate if InvalidateRect or ScrollRect were called and
63 // ClearPendingUpdate was not called.
64 bool HasPendingUpdate() const;
65 void ClearPendingUpdate();
67 PaintUpdate GetPendingUpdate();
69 // Sets the result of a call to the plugin to paint. This includes rects that
70 // are finished painting (ready), and ones that are still in-progress
72 void SetIntermediateResults(const std::vector<ReadyRect>& ready,
73 const std::vector<pp::Rect>& pending);
75 // Returns the rectangles that are ready to be painted.
76 std::vector<ReadyRect> GetReadyRects() const;
78 // The given rect should be repainted.
79 void InvalidateRect(const pp::Rect& rect);
81 // The given rect should be scrolled by the given amounts.
82 void ScrollRect(const pp::Rect& clip_rect, const pp::Point& amount);
85 // This structure is an internal version of PaintUpdate. It's different in
88 // - The scroll damange (area exposed by the scroll operation, if any) is
89 // maintained separately from the dirty rects generated by calling
90 // InvalidateRect. We need to know this distinction for some operations.
92 // - The paint bounds union is computed on the fly so we don't have to keep
93 // a rectangle up to date as we do different operations.
94 class InternalPaintUpdate {
96 InternalPaintUpdate();
97 ~InternalPaintUpdate();
99 // Computes the rect damaged by scrolling within |scroll_rect| by
100 // |scroll_delta|. This rect must be repainted. It is not included in
102 pp::Rect GetScrollDamage() const;
104 pp::Point scroll_delta;
105 pp::Rect scroll_rect;
107 // Does not include the scroll damage rect unless
108 // synthesized_scroll_damage_rect_ is set.
109 std::vector<pp::Rect> paint_rects;
111 // Rectangles that are finished painting.
112 std::vector<ReadyRect> ready_rects;
114 // Whether we have added the scroll damage rect to paint_rects yet or not.
115 bool synthesized_scroll_damage_rect_;
118 pp::Rect ScrollPaintRect(const pp::Rect& paint_rect,
119 const pp::Point& amount) const;
120 void InvalidateScrollRect();
122 // Internal method used by InvalidateRect. If |check_scroll| is true, then the
123 // method checks if there's a pending scroll and if so also invalidates |rect|
124 // in the new scroll position.
125 void InvalidateRectInternal(const pp::Rect& rect, bool check_scroll);
127 InternalPaintUpdate update_;
130 #endif // PDF_PAINT_AGGREGATOR_H_