Index: pdf/paint_aggregator.cc |
=================================================================== |
--- pdf/paint_aggregator.cc (revision 0) |
+++ pdf/paint_aggregator.cc (revision 0) |
@@ -0,0 +1,263 @@ |
+// Copyright (c) 2010 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. |
+ |
+#include "pdf/paint_aggregator.h" |
+ |
+#include <algorithm> |
+ |
+#include "base/logging.h" |
+ |
+// ---------------------------------------------------------------------------- |
+// ALGORITHM NOTES |
+// |
+// We attempt to maintain a scroll rect in the presence of invalidations that |
+// are contained within the scroll rect. If an invalidation crosses a scroll |
+// rect, then we just treat the scroll rect as an invalidation rect. |
+// |
+// For invalidations performed prior to scrolling and contained within the |
+// scroll rect, we offset the invalidation rects to account for the fact that |
+// the consumer will perform scrolling before painting. |
+// |
+// We only support scrolling along one axis at a time. A diagonal scroll will |
+// therefore be treated as an invalidation. |
+// ---------------------------------------------------------------------------- |
+ |
+PaintAggregator::PaintUpdate::PaintUpdate() { |
+} |
+ |
+PaintAggregator::PaintUpdate::~PaintUpdate() { |
+} |
+ |
+PaintAggregator::InternalPaintUpdate::InternalPaintUpdate() : |
+ synthesized_scroll_damage_rect_(false) { |
+} |
+ |
+PaintAggregator::InternalPaintUpdate::~InternalPaintUpdate() { |
+} |
+ |
+pp::Rect PaintAggregator::InternalPaintUpdate::GetScrollDamage() const { |
+ // Should only be scrolling in one direction at a time. |
+ DCHECK(!(scroll_delta.x() && scroll_delta.y())); |
+ |
+ pp::Rect damaged_rect; |
+ |
+ // Compute the region we will expose by scrolling, and paint that into a |
+ // shared memory section. |
+ if (scroll_delta.x()) { |
+ int32_t dx = scroll_delta.x(); |
+ damaged_rect.set_y(scroll_rect.y()); |
+ damaged_rect.set_height(scroll_rect.height()); |
+ if (dx > 0) { |
+ damaged_rect.set_x(scroll_rect.x()); |
+ damaged_rect.set_width(dx); |
+ } else { |
+ damaged_rect.set_x(scroll_rect.right() + dx); |
+ damaged_rect.set_width(-dx); |
+ } |
+ } else { |
+ int32_t dy = scroll_delta.y(); |
+ damaged_rect.set_x(scroll_rect.x()); |
+ damaged_rect.set_width(scroll_rect.width()); |
+ if (dy > 0) { |
+ damaged_rect.set_y(scroll_rect.y()); |
+ damaged_rect.set_height(dy); |
+ } else { |
+ damaged_rect.set_y(scroll_rect.bottom() + dy); |
+ damaged_rect.set_height(-dy); |
+ } |
+ } |
+ |
+ // In case the scroll offset exceeds the width/height of the scroll rect |
+ return scroll_rect.Intersect(damaged_rect); |
+} |
+ |
+PaintAggregator::PaintAggregator() { |
+} |
+ |
+bool PaintAggregator::HasPendingUpdate() const { |
+ return !update_.scroll_rect.IsEmpty() || !update_.paint_rects.empty(); |
+} |
+ |
+void PaintAggregator::ClearPendingUpdate() { |
+ update_ = InternalPaintUpdate(); |
+} |
+ |
+PaintAggregator::PaintUpdate PaintAggregator::GetPendingUpdate() { |
+ // Convert the internal paint update to the external one, which includes a |
+ // bit more precomputed info for the caller. |
+ PaintUpdate ret; |
+ ret.scroll_delta = update_.scroll_delta; |
+ ret.scroll_rect = update_.scroll_rect; |
+ ret.has_scroll = ret.scroll_delta.x() != 0 || ret.scroll_delta.y() != 0; |
+ |
+ // Include the scroll damage (if any) in the paint rects. |
+ // Code invalidates damaged rect here, it pick it up from the list of paint |
+ // rects in the next block. |
+ if (ret.has_scroll && !update_.synthesized_scroll_damage_rect_) { |
+ update_.synthesized_scroll_damage_rect_ = true; |
+ pp::Rect scroll_damage = update_.GetScrollDamage(); |
+ InvalidateRectInternal(scroll_damage, false); |
+ } |
+ |
+ ret.paint_rects.reserve(update_.paint_rects.size() + 1); |
+ for (size_t i = 0; i < update_.paint_rects.size(); i++) |
+ ret.paint_rects.push_back(update_.paint_rects[i]); |
+ |
+ return ret; |
+} |
+ |
+void PaintAggregator::SetIntermediateResults( |
+ const std::vector<ReadyRect>& ready, |
+ const std::vector<pp::Rect>& pending) { |
+ update_.ready_rects.insert( |
+ update_.ready_rects.end(), ready.begin(), ready.end()); |
+ update_.paint_rects = pending; |
+} |
+ |
+std::vector<PaintAggregator::ReadyRect> PaintAggregator::GetReadyRects() const { |
+ return update_.ready_rects; |
+} |
+ |
+void PaintAggregator::InvalidateRect(const pp::Rect& rect) { |
+ InvalidateRectInternal(rect, true); |
+} |
+ |
+void PaintAggregator::ScrollRect(const pp::Rect& clip_rect, |
+ const pp::Point& amount) { |
+ // We only support scrolling along one axis at a time. |
+ if (amount.x() != 0 && amount.y() != 0) { |
+ InvalidateRect(clip_rect); |
+ return; |
+ } |
+ |
+ // We can only scroll one rect at a time. |
+ if (!update_.scroll_rect.IsEmpty() && update_.scroll_rect != clip_rect) { |
+ InvalidateRect(clip_rect); |
+ return; |
+ } |
+ |
+ // Again, we only support scrolling along one axis at a time. Make sure this |
+ // update doesn't scroll on a different axis than any existing one. |
+ if ((amount.x() && update_.scroll_delta.y()) || |
+ (amount.y() && update_.scroll_delta.x())) { |
+ InvalidateRect(clip_rect); |
+ return; |
+ } |
+ |
+ // The scroll rect is new or isn't changing (though the scroll amount may |
+ // be changing). |
+ update_.scroll_rect = clip_rect; |
+ update_.scroll_delta += amount; |
+ |
+ // We might have just wiped out a pre-existing scroll. |
+ if (update_.scroll_delta == pp::Point()) { |
+ update_.scroll_rect = pp::Rect(); |
+ return; |
+ } |
+ |
+ // Adjust any paint rects that intersect the scroll. For the portion of the |
+ // paint that is inside the scroll area, move it by the scroll amount and |
+ // replace the existing paint with it. For the portion (if any) that is |
+ // outside the scroll, just invalidate it. |
+ std::vector<pp::Rect> leftover_rects; |
+ for (size_t i = 0; i < update_.paint_rects.size(); ++i) { |
+ if (!update_.scroll_rect.Intersects(update_.paint_rects[i])) |
+ continue; |
+ |
+ pp::Rect intersection = |
+ update_.paint_rects[i].Intersect(update_.scroll_rect); |
+ pp::Rect rect = update_.paint_rects[i]; |
+ while (!rect.IsEmpty()) { |
+ pp::Rect leftover = rect.Subtract(intersection); |
+ if (leftover.IsEmpty()) |
+ break; |
+ // Don't want to call InvalidateRectInternal now since it'll modify |
+ // update_.paint_rects, so keep track of this and do it below. |
+ leftover_rects.push_back(leftover); |
+ rect = rect.Subtract(leftover); |
+ } |
+ |
+ update_.paint_rects[i] = ScrollPaintRect(intersection, amount); |
+ |
+ // The rect may have been scrolled out of view. |
+ if (update_.paint_rects[i].IsEmpty()) { |
+ update_.paint_rects.erase(update_.paint_rects.begin() + i); |
+ i--; |
+ } |
+ } |
+ |
+ for (size_t i = 0; i < leftover_rects.size(); ++i) |
+ InvalidateRectInternal(leftover_rects[i], false); |
+ |
+ for (size_t i = 0; i < update_.ready_rects.size(); ++i) { |
+ if (update_.scroll_rect.Contains(update_.ready_rects[i].rect)) { |
+ update_.ready_rects[i].rect = |
+ ScrollPaintRect(update_.ready_rects[i].rect, amount); |
+ } |
+ } |
+ |
+ if (update_.synthesized_scroll_damage_rect_) { |
+ pp::Rect damage = update_.GetScrollDamage(); |
+ InvalidateRect(damage); |
+ } |
+} |
+ |
+pp::Rect PaintAggregator::ScrollPaintRect(const pp::Rect& paint_rect, |
+ const pp::Point& amount) const { |
+ pp::Rect result = paint_rect; |
+ result.Offset(amount); |
+ result = update_.scroll_rect.Intersect(result); |
+ return result; |
+} |
+ |
+void PaintAggregator::InvalidateScrollRect() { |
+ pp::Rect scroll_rect = update_.scroll_rect; |
+ update_.scroll_rect = pp::Rect(); |
+ update_.scroll_delta = pp::Point(); |
+ InvalidateRect(scroll_rect); |
+} |
+ |
+void PaintAggregator::InvalidateRectInternal(const pp::Rect& rect_old, |
+ bool check_scroll) { |
+ pp::Rect rect = rect_old; |
+ // Check if any rects that are ready to be painted overlap. |
+ for (size_t i = 0; i < update_.ready_rects.size(); ++i) { |
+ const pp::Rect& existing_rect = update_.ready_rects[i].rect; |
+ if (rect.Intersects(existing_rect)) { |
+ // Re-invalidate in case the union intersects other paint rects. |
+ rect = existing_rect.Union(rect); |
+ update_.ready_rects.erase(update_.ready_rects.begin() + i); |
+ break; |
+ } |
+ } |
+ |
+ bool add_paint = true; |
+ |
+ // Combine overlapping paints using smallest bounding box. |
+ for (size_t i = 0; i < update_.paint_rects.size(); ++i) { |
+ const pp::Rect& existing_rect = update_.paint_rects[i]; |
+ if (existing_rect.Contains(rect)) // Optimize out redundancy. |
+ add_paint = false; |
+ if (rect.Intersects(existing_rect) || rect.SharesEdgeWith(existing_rect)) { |
+ // Re-invalidate in case the union intersects other paint rects. |
+ pp::Rect combined_rect = existing_rect.Union(rect); |
+ update_.paint_rects.erase(update_.paint_rects.begin() + i); |
+ InvalidateRectInternal(combined_rect, check_scroll); |
+ add_paint = false; |
+ } |
+ } |
+ |
+ if (add_paint) { |
+ // Add a non-overlapping paint. |
+ update_.paint_rects.push_back(rect); |
+ } |
+ |
+ // If the new paint overlaps with a scroll, then also invalidate the rect in |
+ // its new position. |
+ if (check_scroll && |
+ !update_.scroll_rect.IsEmpty() && |
+ update_.scroll_rect.Intersects(rect)) { |
+ InvalidateRectInternal(ScrollPaintRect(rect, update_.scroll_delta), false); |
+ } |
+} |
Property changes on: pdf\paint_aggregator.cc |
___________________________________________________________________ |
Added: svn:eol-style |
+ LF |