Initial QuadTree implementation

tests/BBoxHierarchyTest.cpp

Index: tests/BBoxHierarchyTest.cpp
diff --git a/tests/BBoxHierarchyTest.cpp b/tests/BBoxHierarchyTest.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..a562da24f89c75ce11da4942dc91503eff8e9360
--- /dev/null
+++ b/tests/BBoxHierarchyTest.cpp
@@ -0,0 +1,180 @@
+/*
+ * Copyright 2012 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "Test.h"
+#include "SkRandom.h"
+#include "SkQuadTree.h"
+#include "SkRTree.h"
+#include "SkTSort.h"
+
+static const size_t RTREE_MIN_CHILDREN = 6;
+static const size_t RTREE_MAX_CHILDREN = 11;
+static const size_t QUADTREE_MIN_CHILDREN = 4;
+static const size_t QUADTREE_MAX_CHILDREN = 0; // No hard limit for quadtree
+
+static const int NUM_RECTS = 200;
+static const size_t NUM_ITERATIONS = 100;
+static const size_t NUM_QUERIES = 50;
+
+static const int MAX_SIZE = 1000;
+
+struct DataRect {
+    SkIRect rect;
+    void* data;
+};
+
+static SkIRect random_rect(SkRandom& rand) {
+    SkIRect rect = {0,0,0,0};
+    while (rect.isEmpty()) {
+        rect.fLeft   = rand.nextS() % MAX_SIZE;
+        rect.fRight  = rand.nextS() % MAX_SIZE;
+        rect.fTop    = rand.nextS() % MAX_SIZE;
+        rect.fBottom = rand.nextS() % MAX_SIZE;
+        rect.sort();
+    }
+    return rect;
+}
+
+static void random_data_rects(SkRandom& rand, DataRect out[], int n) {
+    for (int i = 0; i < n; ++i) {
+        out[i].rect = random_rect(rand);
+        out[i].data = reinterpret_cast<void*>(i);
+    }
+}
+
+static bool verify_query(SkIRect query, DataRect rects[],
+                         SkTDArray<void*>& found) {
+    SkTDArray<void*> expected;
+    // manually intersect with every rectangle
+    for (int i = 0; i < NUM_RECTS; ++i) {
+        if (SkIRect::IntersectsNoEmptyCheck(query, rects[i].rect)) {
+            expected.push(rects[i].data);
+        }
+    }
+
+    if (expected.count() != found.count()) {
+        return false;
+    }
+
+    if (0 == expected.count()) {
+        return true;
+    }
+
+    // Just cast to long since sorting by the value of the void*'s was being problematic...
+    SkTQSort(reinterpret_cast<long*>(expected.begin()),
+             reinterpret_cast<long*>(expected.end() - 1));
+    SkTQSort(reinterpret_cast<long*>(found.begin()),
+             reinterpret_cast<long*>(found.end() - 1));
+    return found == expected;
+}
+
+static void run_queries(skiatest::Reporter* reporter, SkRandom& rand, DataRect rects[],
+                        SkBBoxHierarchy& tree) {
+    for (size_t i = 0; i < NUM_QUERIES; ++i) {
+        SkTDArray<void*> hits;
+        SkIRect query = random_rect(rand);
+        tree.search(query, &hits);
+        REPORTER_ASSERT(reporter, verify_query(query, rects, hits));
+    }
+}
+
+static void tree_test_main(SkBBoxHierarchy* tree, int minChildren, int maxChildren,
+                           skiatest::Reporter* reporter) {
+    DataRect rects[NUM_RECTS];
+    SkRandom rand;
+    REPORTER_ASSERT(reporter, NULL != tree);
+
+    int expectedDepthMin = -1;
+    int expectedDepthMax = -1;
+
+    int tmp = NUM_RECTS;
+    if (maxChildren > 0) {
+        while (tmp > 0) {
+            tmp -= static_cast<int>(pow(static_cast<double>(maxChildren),
+                                    static_cast<double>(expectedDepthMin + 1)));
+            ++expectedDepthMin;
+        }
+    }
+
+    tmp = NUM_RECTS;
+    if (minChildren > 0) {
+        while (tmp > 0) {
+            tmp -= static_cast<int>(pow(static_cast<double>(minChildren),
+                                    static_cast<double>(expectedDepthMax + 1)));
+            ++expectedDepthMax;
+        }
+    }
+
+    for (size_t i = 0; i < NUM_ITERATIONS; ++i) {
+        random_data_rects(rand, rects, NUM_RECTS);
+
+        // First try bulk-loaded inserts
+        for (int i = 0; i < NUM_RECTS; ++i) {
+            tree->insert(rects[i].data, rects[i].rect, true);
+        }
+        tree->flushDeferredInserts();
+        run_queries(reporter, rand, rects, *tree);
+        REPORTER_ASSERT(reporter, NUM_RECTS == tree->getCount());
+        REPORTER_ASSERT(reporter,
+            ((expectedDepthMin <= 0) || (expectedDepthMin <= tree->getDepth())) &&
+            ((expectedDepthMax <= 0) || (expectedDepthMax >= tree->getDepth())));
+        tree->clear();
+        REPORTER_ASSERT(reporter, 0 == tree->getCount());
+
+        // Then try immediate inserts
+        for (int i = 0; i < NUM_RECTS; ++i) {
+            tree->insert(rects[i].data, rects[i].rect);
+        }
+        run_queries(reporter, rand, rects, *tree);
+        REPORTER_ASSERT(reporter, NUM_RECTS == tree->getCount());
+        REPORTER_ASSERT(reporter,
+            ((expectedDepthMin <= 0) || (expectedDepthMin <= tree->getDepth())) &&
+            ((expectedDepthMax <= 0) || (expectedDepthMax >= tree->getDepth())));
+        tree->clear();
+        REPORTER_ASSERT(reporter, 0 == tree->getCount());
+
+        // And for good measure try immediate inserts, but in reversed order
+        for (int i = NUM_RECTS - 1; i >= 0; --i) {
+            tree->insert(rects[i].data, rects[i].rect);
+        }
+        run_queries(reporter, rand, rects, *tree);
+        REPORTER_ASSERT(reporter, NUM_RECTS == tree->getCount());
+        REPORTER_ASSERT(reporter,
+            ((expectedDepthMin < 0) || (expectedDepthMin <= tree->getDepth())) &&
+            ((expectedDepthMax < 0) || (expectedDepthMax >= tree->getDepth())));
+        tree->clear();
+        REPORTER_ASSERT(reporter, 0 == tree->getCount());
+    }
+}
+
+DEF_TEST(BBoxHierarchy, reporter) {
+    // RTree
+    {
+        SkRTree* rtree = SkRTree::Create(RTREE_MIN_CHILDREN, RTREE_MAX_CHILDREN);
+        SkAutoUnref au(rtree);
+        tree_test_main(rtree, RTREE_MIN_CHILDREN, RTREE_MAX_CHILDREN, reporter);
+
+        // Rtree that orders input rectangles on deferred insert.
+        SkRTree* unsortedRtree = SkRTree::Create(RTREE_MIN_CHILDREN, RTREE_MAX_CHILDREN, 1, false);
+        SkAutoUnref auo(unsortedRtree);
+        tree_test_main(unsortedRtree, RTREE_MIN_CHILDREN, RTREE_MAX_CHILDREN, reporter);
+    }
+
+    // QuadTree
+    {
+        SkQuadTree* quadtree = SkQuadTree::Create(
+            SkIRect::MakeLTRB(-MAX_SIZE, -MAX_SIZE, MAX_SIZE, MAX_SIZE));
+        SkAutoUnref au(quadtree);
+        tree_test_main(quadtree, QUADTREE_MIN_CHILDREN, QUADTREE_MAX_CHILDREN, reporter);
+
+        // QuadTree that orders input rectangles on deferred insert.
+        SkQuadTree* unsortedQuadTree = SkQuadTree::Create(
+            SkIRect::MakeLTRB(-MAX_SIZE, -MAX_SIZE, MAX_SIZE, MAX_SIZE));
+        SkAutoUnref auo(unsortedQuadTree);
+        tree_test_main(unsortedQuadTree, QUADTREE_MIN_CHILDREN, QUADTREE_MAX_CHILDREN, reporter);
+    }
+}