Chromium Code Reviews
chromiumcodereview-hr@appspot.gserviceaccount.com (chromiumcodereview-hr) | Please choose your nickname with Settings | Help | Chromium Project | Gerrit Changes | Sign out
(3559)

Unified Diff: cc/output/bsp_tree.cc

Issue 384083002: WIP BSP Tree for 3D Layer Sorting (Closed) Base URL: https://chromium.googlesource.com/chromium/src.git@master
Patch Set: Created 6 years, 5 months ago
Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.
Jump to:
View side-by-side diff with in-line comments
Download patch
« no previous file with comments | « cc/output/bsp_tree.h ('k') | cc/output/bsp_tree_unittest.cc » ('j') | no next file with comments »
Expand Comments ('e') | Collapse Comments ('c') | Show Comments Hide Comments ('s')
Index: cc/output/bsp_tree.cc
diff --git a/cc/output/bsp_tree.cc b/cc/output/bsp_tree.cc
new file mode 100644
index 0000000000000000000000000000000000000000..2755c0b77971aa407c96a20638a399380bb87329
--- /dev/null
+++ b/cc/output/bsp_tree.cc
@@ -0,0 +1,121 @@
+// Copyright 2014 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 "cc/output/bsp_tree.h"
+
+#include <list>
+#include <vector>
+
+#include "base/memory/scoped_ptr.h"
+#include "cc/base/scoped_ptr_deque.h"
+#include "cc/base/scoped_ptr_vector.h"
+#include "cc/output/bsp_compare_result.h"
+#include "cc/quads/draw_polygon.h"
+
+namespace cc {
+
+BspNode::BspNode(scoped_ptr<DrawPolygon> data) : node_data(data.Pass()) {
+}
+
+BspNode::~BspNode() {
+}
+
+BspTree::BspTree(ScopedPtrDeque<DrawPolygon>* list) {
+ if (list->size() == 0)
+ return;
+
+ root_ = scoped_ptr<BspNode>(new BspNode(list->take_front()));
+ BuildTree(root_.get(), list);
+}
+
+// The idea behind using a deque for BuildTree's input is that we want to be
+// able to place polygons that we've decided aren't splitting plane candidates
+// at the back of the queue while moving the candidate splitting planes to the
+// front when the heuristic decides that they're a better choice. This way we
+// can always simply just take from the front of the deque for our node's
+// data.
+void BspTree::BuildTree(BspNode* node,
+ ScopedPtrDeque<DrawPolygon>* polygon_list) {
+ ScopedPtrDeque<DrawPolygon> front_list;
+ ScopedPtrDeque<DrawPolygon> back_list;
+
+ // We take in a list of polygons at this level of the tree, and have to
+ // find a splitting plane, then classify polygons as either in front of
+ // or behind that splitting plane.
+ while (polygon_list->size() > 0) {
+ // Is this particular polygon in front of or behind our splitting polygon.
+ BspCompareResult comparer_result =
+ GetNodePositionRelative(*polygon_list->front(), *(node->node_data));
+
+ // If it's clearly behind or in front of the splitting plane, we use the
+ // heuristic to decide whether or not we should put it at the back
+ // or front of the list.
+ switch (comparer_result) {
+ case BSP_FRONT:
+ front_list.push_back(polygon_list->take_front().Pass());
+ break;
+ case BSP_BACK:
+ back_list.push_back(polygon_list->take_front().Pass());
+ break;
+ case BSP_SPLIT:
+ {
+ scoped_ptr<DrawPolygon> polygon;
+ scoped_ptr<DrawPolygon> new_front;
+ scoped_ptr<DrawPolygon> new_back;
+ bool split_result = false;
+ // Time to split this geometry, *it needs to be split by node_data.
+ polygon = polygon_list->take_front();
+ split_result =
+ polygon->Split(*(node->node_data), &new_front, &new_back);
+ DCHECK(split_result);
+ if (!split_result) {
+ break;
+ }
+ front_list.push_back(new_front.Pass());
+ back_list.push_back(new_back.Pass());
+ break;
+ }
+ case BSP_COPLANAR_FRONT:
+ node->coplanars_front.push_back(polygon_list->take_front());
+ break;
+ case BSP_COPLANAR_BACK:
+ node->coplanars_back.push_back(polygon_list->take_front());
+ break;
+ default:
+ NOTREACHED();
+ break;
+ }
+ }
+
+ // Build the back subtree using the front of the back_list as our splitter.
+ if (back_list.size() > 0) {
+ node->back_child = scoped_ptr<BspNode>(new BspNode(back_list.take_front()));
+ BuildTree(node->back_child.get(), &back_list);
+ }
+
+ // Build the front subtree using the front of the front_list as our splitter.
+ if (front_list.size() > 0) {
+ node->front_child =
+ scoped_ptr<BspNode>(new BspNode(front_list.take_front()));
+ BuildTree(node->front_child.get(), &front_list);
+ }
+}
+
+BspCompareResult BspTree::GetNodePositionRelative(const DrawPolygon& node_a,
+ const DrawPolygon& node_b) {
+ return DrawPolygon::SideCompare(node_a, node_b);
+}
+
+// The base comparer with 0,0,0 as camera position facing forward
+BspCompareResult BspTree::GetCameraPositionRelative(const DrawPolygon& node) {
+ if (node.normal().z() > 0.0f) {
+ return BSP_FRONT;
+ }
+ return BSP_BACK;
+}
+
+BspTree::~BspTree() {
+}
+
+} // namespace cc
« no previous file with comments | « cc/output/bsp_tree.h ('k') | cc/output/bsp_tree_unittest.cc » ('j') | no next file with comments »

Powered by Google App Engine
This is Rietveld 408576698