replicant-frameworks_native/libs/ui/tests/Region_test.cpp
Chris Craik 3e010f3138 Add createTJunctionFreeRegion
T-junction free regions are useful for rendering regions with various
geometric transformations, and the Region's span-ordered, sorted rect
list supports T-junction free storage without modification.

This approach creates a T-junction free region by splitting each
rectangle that is part of a vertical T-junction. This approach is two
pass (up and down) so that divisions can trickle up/down to other
adjacent spans.

Change-Id: Ifcf5e6fe0034c96b00ef09a4433b2b0fce8f4300
2013-02-27 11:13:03 -08:00

157 lines
4.0 KiB
C++

/*
* Copyright (C) 2013 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define LOG_TAG "RegionTest"
#include <stdlib.h>
#include <ui/Region.h>
#include <ui/Rect.h>
#include <gtest/gtest.h>
namespace android {
class RegionTest : public testing::Test {
protected:
void checkVertTJunction(const Rect* lhs, const Rect* rhs) {
EXPECT_FALSE((rhs->right > lhs->left && rhs->right < lhs->right) ||
(rhs->left > lhs->left && rhs->left < lhs->right));
}
void verifyNoTJunctions(const Region& r) {
for (const Rect* current = r.begin(); current < r.end(); current++) {
for (const Rect* other = current - 1; other >= r.begin(); other--) {
if (other->bottom < current->top) break;
if (other->bottom != current->top) continue;
checkVertTJunction(current, other);
}
for (const Rect* other = current + 1; other < r.end(); other++) {
if (other->top > current->bottom) break;
if (other->top != current->bottom) continue;
checkVertTJunction(current, other);
}
}
}
void checkTJunctionFreeFromRegion(const Region& original, int expectedCount = -1) {
Region modified = Region::createTJunctionFreeRegion(original);
verifyNoTJunctions(modified);
if (expectedCount != -1) {
EXPECT_EQ(modified.end() - modified.begin(), expectedCount);
}
EXPECT_TRUE((original ^ modified).isEmpty());
}
};
TEST_F(RegionTest, MinimalDivision_TJunction) {
Region r;
// | x |
// |xxx|
r.clear();
r.orSelf(Rect(1, 0, 2, 1));
r.orSelf(Rect(0, 1, 3, 2));
checkTJunctionFreeFromRegion(r, 4);
// | x |
// | |
// |xxx|
r.clear();
r.orSelf(Rect(1, 0, 2, 1));
r.orSelf(Rect(0, 2, 3, 3));
checkTJunctionFreeFromRegion(r, 2);
}
TEST_F(RegionTest, Trivial_TJunction) {
Region r;
checkTJunctionFreeFromRegion(r);
r.orSelf(Rect(100, 100, 500, 500));
checkTJunctionFreeFromRegion(r);
}
TEST_F(RegionTest, Simple_TJunction) {
Region r;
// | x |
// |xxxx|
// |xxxx|
// |xxxx|
r.clear();
r.orSelf(Rect(1, 0, 2, 1));
r.orSelf(Rect(0, 1, 3, 3));
checkTJunctionFreeFromRegion(r);
// | x |
// |xx |
// |xxx|
r.clear();
r.orSelf(Rect(2,0,4,2));
r.orSelf(Rect(0,2,4,4));
r.orSelf(Rect(0,4,6,6));
checkTJunctionFreeFromRegion(r);
// |x x|
// |xxx|
// |x x|
r.clear();
r.orSelf(Rect(0,0,2,6));
r.orSelf(Rect(4,0,6,6));
r.orSelf(Rect(0,2,6,4));
checkTJunctionFreeFromRegion(r);
// |xxx|
// | x |
// | x |
r.clear();
r.orSelf(Rect(0,0,6,2));
r.orSelf(Rect(2,2,4,6));
checkTJunctionFreeFromRegion(r);
}
TEST_F(RegionTest, Bigger_TJunction) {
Region r;
// |xxxx |
// | xxxx |
// | xxxx |
// | xxxx|
for (int i = 0; i < 4; i++) {
r.orSelf(Rect(i,i,i+4,i+1));
}
checkTJunctionFreeFromRegion(r, 16);
}
#define ITER_MAX 1000
#define X_MAX 8
#define Y_MAX 8
TEST_F(RegionTest, Random_TJunction) {
Region r;
srandom(12345);
for (int iter = 0; iter < ITER_MAX; iter++) {
r.clear();
for (int i = 0; i < X_MAX; i++) {
for (int j = 0; j < Y_MAX; j++) {
if (random() % 2) {
r.orSelf(Rect(i, j, i + 1, j + 1));
}
}
}
checkTJunctionFreeFromRegion(r);
}
}
}; // namespace android