/*
* Copyright (C) 2007 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 "Region"
#include <inttypes.h>
#include <limits.h>
#include <utils/Log.h>
#include <utils/String8.h>
#include <utils/CallStack.h>
#include <ui/Rect.h>
#include <ui/Region.h>
#include <ui/Point.h>
#include <private/ui/RegionHelper.h>
// ----------------------------------------------------------------------------
#define VALIDATE_REGIONS (false)
#define VALIDATE_WITH_CORECG (false)
// ----------------------------------------------------------------------------
#if VALIDATE_WITH_CORECG
#include <core/SkRegion.h>
#endif
namespace android {
// ----------------------------------------------------------------------------
enum {
op_nand = region_operator<Rect>::op_nand,
op_and = region_operator<Rect>::op_and,
op_or = region_operator<Rect>::op_or,
op_xor = region_operator<Rect>::op_xor
};
enum {
direction_LTR,
direction_RTL
};
const Region Region::INVALID_REGION(Rect::INVALID_RECT);
// ----------------------------------------------------------------------------
Region::Region() {
mStorage.add(Rect(0,0));
}
Region::Region(const Region& rhs)
: mStorage(rhs.mStorage)
{
#if VALIDATE_REGIONS
validate(rhs, "rhs copy-ctor");
#endif
}
Region::Region(const Rect& rhs) {
mStorage.add(rhs);
}
Region::~Region()
{
}
/**
* Copy rects from the src vector into the dst vector, resolving vertical T-Junctions along the way
*
* First pass through, divideSpanRTL will be set because the 'previous span' (indexing into the dst
* vector) will be reversed. Each rectangle in the original list, starting from the bottom, will be
* compared with the span directly below, and subdivided as needed to resolve T-junctions.
*
* The resulting temporary vector will be a completely reversed copy of the original, without any
* bottom-up T-junctions.
*
* Second pass through, divideSpanRTL will be false since the previous span will index into the
* final, correctly ordered region buffer. Each rectangle will be compared with the span directly
* above it, and subdivided to resolve any remaining T-junctions.
*/
static void reverseRectsResolvingJunctions(const Rect* begin, const Rect* end,
Vector<Rect>& dst, int spanDirection) {
dst.clear();
const Rect* current = end - 1;
int lastTop = current->top;
// add first span immediately
do {
dst.add(*current);
current--;
} while (current->top == lastTop && current >= begin);
int beginLastSpan = -1;
int endLastSpan = -1;
int top = -1;
int bottom = -1;
// for all other spans, split if a t-junction exists in the span directly above
while (current >= begin) {
if (current->top != (current + 1)->top) {
// new span
if ((spanDirection == direction_RTL && current->bottom != (current + 1)->top) ||
(spanDirection == direction_LTR && current->top != (current + 1)->bottom)) {
// previous span not directly adjacent, don't check for T junctions
beginLastSpan = INT_MAX;
} else {
beginLastSpan = endLastSpan + 1;
}
endLastSpan = static_cast<int>(dst.size()) - 1;
top = current->top;
bottom = current->bottom;
}
int left = current->left;
int right = current->right;
for (int prevIndex = beginLastSpan; prevIndex <= endLastSpan; prevIndex++) {
// prevIndex can't be -1 here because if endLastSpan is set to a
// value greater than -1 (allowing the loop to execute),
// beginLastSpan (and therefore prevIndex) will also be increased
const Rect prev = dst[static_cast<size_t>(prevIndex)];
if (spanDirection == direction_RTL) {
// iterating over previous span RTL, quit if it's too far left
if (prev.right <= left) break;
if (prev.right > left && prev.right < right) {
dst.add(Rect(prev.right, top, right, bottom));
right = prev.right;
}
if (prev.left > left && prev.left < right) {
dst.add(Rect(prev.left, top, right, bottom));
right = prev.left;
}
// if an entry in the previous span is too far right, nothing further left in the
// current span will need it
if (prev.left >= right) {
beginLastSpan = prevIndex;
}
} else {
// iterating over previous span LTR, quit if it's too far right
if (prev.left >= right) break;
if (prev.left > left && prev.left < right) {
dst.add(Rect(left, top, prev.left, bottom));
left = prev.left;
}
if (prev.right > left && prev.right < right) {
dst.add(Rect(left, top, prev.right, bottom));
left = prev.right;
}
// if an entry in the previous span is too far left, nothing further right in the
// current span will need it
if (prev.right <= left) {
beginLastSpan = prevIndex;
}
}
}
if (left < right) {
dst.add(Rect(left, top, right, bottom));
}
current--;
}
}
/**
* Creates a new region with the same data as the argument, but divides rectangles as necessary to
* remove T-Junctions
*
* Note: the output will not necessarily be a very efficient representation of the region, since it
* may be that a triangle-based approach would generate significantly simpler geometry
*/
Region Region::createTJunctionFreeRegion(const Region& r) {
if (r.isEmpty()) return r;
if (r.isRect()) return r;
Vector<Rect> reversed;
reverseRectsResolvingJunctions(r.begin(), r.end(), reversed, direction_RTL);
Region outputRegion;
reverseRectsResolvingJunctions(reversed.begin(), reversed.end(),
outputRegion.mStorage, direction_LTR);
outputRegion.mStorage.add(r.getBounds()); // to make region valid, mStorage must end with bounds
#if VALIDATE_REGIONS
validate(outputRegion, "T-Junction free region");
#endif
return outputRegion;
}
Region& Region::operator = (const Region& rhs)
{
#if VALIDATE_REGIONS
validate(*this, "this->operator=");
validate(rhs, "rhs.operator=");
#endif
mStorage = rhs.mStorage;
return *this;
}
Region& Region::makeBoundsSelf()
{
if (mStorage.size() >= 2) {
const Rect bounds(getBounds());
mStorage.clear();
mStorage.add(bounds);
}
return *this;
}
bool Region::contains(const Point& point) const {
return contains(point.x, point.y);
}
bool Region::contains(int x, int y) const {
const_iterator cur = begin();
const_iterator const tail = end();
while (cur != tail) {
if (y >= cur->top && y < cur->bottom && x >= cur->left && x < cur->right) {
return true;
}
cur++;
}
return false;
}
void Region::clear()
{
mStorage.clear();
mStorage.add(Rect(0,0));
}
void Region::set(const Rect& r)
{
mStorage.clear();
mStorage.add(r);
}
void Region::set(int32_t w, int32_t h)
{
mStorage.clear();
mStorage.add(Rect(w, h));
}
void Region::set(uint32_t w, uint32_t h)
{
mStorage.clear();
mStorage.add(Rect(w, h));
}
bool Region::isTriviallyEqual(const Region& region) const {
return begin() == region.begin();
}
// ----------------------------------------------------------------------------
void Region::addRectUnchecked(int l, int t, int r, int b)
{
Rect rect(l,t,r,b);
size_t where = mStorage.size() - 1;
mStorage.insertAt(rect, where, 1);
}
// ----------------------------------------------------------------------------
Region& Region::orSelf(const Rect& r) {
return operationSelf(r, op_or);
}
Region& Region::xorSelf(const Rect& r) {
return operationSelf(r, op_xor);
}
Region& Region::andSelf(const Rect& r) {
return operationSelf(r, op_and);
}
Region& Region::subtractSelf(const Rect& r) {
return operationSelf(r, op_nand);
}
Region& Region::operationSelf(const Rect& r, uint32_t op) {
Region lhs(*this);
boolean_operation(op, *this, lhs, r);
return *this;
}
// ----------------------------------------------------------------------------
Region& Region::orSelf(const Region& rhs) {
return operationSelf(rhs, op_or);
}
Region& Region::xorSelf(const Region& rhs) {
return operationSelf(rhs, op_xor);
}
Region& Region::andSelf(const Region& rhs) {
return operationSelf(rhs, op_and);
}
Region& Region::subtractSelf(const Region& rhs) {
return operationSelf(rhs, op_nand);
}
Region& Region::operationSelf(const Region& rhs, uint32_t op) {
Region lhs(*this);
boolean_operation(op, *this, lhs, rhs);
return *this;
}
Region& Region::translateSelf(int x, int y) {
if (x|y) translate(*this, x, y);
return *this;
}
// ----------------------------------------------------------------------------
const Region Region::merge(const Rect& rhs) const {
return operation(rhs, op_or);
}
const Region Region::mergeExclusive(const Rect& rhs) const {
return operation(rhs, op_xor);
}
const Region Region::intersect(const Rect& rhs) const {
return operation(rhs, op_and);
}
const Region Region::subtract(const Rect& rhs) const {
return operation(rhs, op_nand);
}
const Region Region::operation(const Rect& rhs, uint32_t op) const {
Region result;
boolean_operation(op, result, *this, rhs);
return result;
}
// ----------------------------------------------------------------------------
const Region Region::merge(const Region& rhs) const {
return operation(rhs, op_or);
}
const Region Region::mergeExclusive(const Region& rhs) const {
return operation(rhs, op_xor);
}
const Region Region::intersect(const Region& rhs) const {
return operation(rhs, op_and);
}
const Region Region::subtract(const Region& rhs) const {
return operation(rhs, op_nand);
}
const Region Region::operation(const Region& rhs, uint32_t op) const {
Region result;
boolean_operation(op, result, *this, rhs);
return result;
}
const Region Region::translate(int x, int y) const {
Region result;
translate(result, *this, x, y);
return result;
}
// ----------------------------------------------------------------------------
Region& Region::orSelf(const Region& rhs, int dx, int dy) {
return operationSelf(rhs, dx, dy, op_or);
}
Region& Region::xorSelf(const Region& rhs, int dx, int dy) {
return operationSelf(rhs, dx, dy, op_xor);
}
Region& Region::andSelf(const Region& rhs, int dx, int dy) {
return operationSelf(rhs, dx, dy, op_and);
}
Region& Region::subtractSelf(const Region& rhs, int dx, int dy) {
return operationSelf(rhs, dx, dy, op_nand);
}
Region& Region::operationSelf(const Region& rhs, int dx, int dy, uint32_t op) {
Region lhs(*this);
boolean_operation(op, *this, lhs, rhs, dx, dy);
return *this;
}
// ----------------------------------------------------------------------------
const Region Region::merge(const Region& rhs, int dx, int dy) const {
return operation(rhs, dx, dy, op_or);
}
const Region Region::mergeExclusive(const Region& rhs, int dx, int dy) const {
return operation(rhs, dx, dy, op_xor);
}
const Region Region::intersect(const Region& rhs, int dx, int dy) const {
return operation(rhs, dx, dy, op_and);
}
const Region Region::subtract(const Region& rhs, int dx, int dy) const {
return operation(rhs, dx, dy, op_nand);
}
const Region Region::operation(const Region& rhs, int dx, int dy, uint32_t op) const {
Region result;
boolean_operation(op, result, *this, rhs, dx, dy);
return result;
}
// ----------------------------------------------------------------------------
// This is our region rasterizer, which merges rects and spans together
// to obtain an optimal region.
class Region::rasterizer : public region_operator<Rect>::region_rasterizer
{
Rect bounds;
Vector<Rect>& storage;
Rect* head;
Rect* tail;
Vector<Rect> span;
Rect* cur;
public:
explicit rasterizer(Region& reg)
: bounds(INT_MAX, 0, INT_MIN, 0), storage(reg.mStorage), head(), tail(), cur() {
storage.clear();
}
virtual ~rasterizer();
virtual void operator()(const Rect& rect);
private:
template<typename T>
static inline T min(T rhs, T lhs) { return rhs < lhs ? rhs : lhs; }
template<typename T>
static inline T max(T rhs, T lhs) { return rhs > lhs ? rhs : lhs; }
void flushSpan();
};
Region::rasterizer::~rasterizer()
{
if (span.size()) {
flushSpan();
}
if (storage.size()) {
bounds.top = storage.itemAt(0).top;
bounds.bottom = storage.top().bottom;
if (storage.size() == 1) {
storage.clear();
}
} else {
bounds.left = 0;
bounds.right = 0;
}
storage.add(bounds);
}
void Region::rasterizer::operator()(const Rect& rect)
{
//ALOGD(">>> %3d, %3d, %3d, %3d",
// rect.left, rect.top, rect.right, rect.bottom);
if (span.size()) {
if (cur->top != rect.top) {
flushSpan();
} else if (cur->right == rect.left) {
cur->right = rect.right;
return;
}
}
span.add(rect);
cur = span.editArray() + (span.size() - 1);
}
void Region::rasterizer::flushSpan()
{
bool merge = false;
if (tail-head == ssize_t(span.size())) {
Rect const* p = span.editArray();
Rect const* q = head;
if (p->top == q->bottom) {
merge = true;
while (q != tail) {
if ((p->left != q->left) || (p->right != q->right)) {
merge = false;
break;
}
p++;
q++;
}
}
}
if (merge) {
const int bottom = span[0].bottom;
Rect* r = head;
while (r != tail) {
r->bottom = bottom;
r++;
}
} else {
bounds.left = min(span.itemAt(0).left, bounds.left);
bounds.right = max(span.top().right, bounds.right);
storage.appendVector(span);
tail = storage.editArray() + storage.size();
head = tail - span.size();
}
span.clear();
}
bool Region::validate(const Region& reg, const char* name, bool silent)
{
bool result = true;
const_iterator cur = reg.begin();
const_iterator const tail = reg.end();
const_iterator prev = cur;
Rect b(*prev);
while (cur != tail) {
if (cur->isValid() == false) {
// We allow this particular flavor of invalid Rect, since it is used
// as a signal value in various parts of the system
if (*cur != Rect::INVALID_RECT) {
ALOGE_IF(!silent, "%s: region contains an invalid Rect", name);
result = false;
}
}
if (cur->right > region_operator<Rect>::max_value) {
ALOGE_IF(!silent, "%s: rect->right > max_value", name);
result = false;
}
if (cur->bottom > region_operator<Rect>::max_value) {
ALOGE_IF(!silent, "%s: rect->right > max_value", name);
result = false;
}
if (prev != cur) {
b.left = b.left < cur->left ? b.left : cur->left;
b.top = b.top < cur->top ? b.top : cur->top;
b.right = b.right > cur->right ? b.right : cur->right;
b.bottom = b.bottom > cur->bottom ? b.bottom : cur->bottom;
if ((*prev < *cur) == false) {
ALOGE_IF(!silent, "%s: region's Rects not sorted", name);
result = false;
}
if (cur->top == prev->top) {
if (cur->bottom != prev->bottom) {
ALOGE_IF(!silent, "%s: invalid span %p", name, cur);
result = false;
} else if (cur->left < prev->right) {
ALOGE_IF(!silent,
"%s: spans overlap horizontally prev=%p, cur=%p",
name, prev, cur);
result = false;
}
} else if (cur->top < prev->bottom) {
ALOGE_IF(!silent,
"%s: spans overlap vertically prev=%p, cur=%p",
name, prev, cur);
result = false;
}
prev = cur;
}
cur++;
}
if (b != reg.getBounds()) {
result = false;
ALOGE_IF(!silent,
"%s: invalid bounds [%d,%d,%d,%d] vs. [%d,%d,%d,%d]", name,
b.left, b.top, b.right, b.bottom,
reg.getBounds().left, reg.getBounds().top,
reg.getBounds().right, reg.getBounds().bottom);
}
if (reg.mStorage.size() == 2) {
result = false;
ALOGE_IF(!silent, "%s: mStorage size is 2, which is never valid", name);
}
if (result == false && !silent) {
reg.dump(name);
CallStack stack(LOG_TAG);
}
return result;
}
void Region::boolean_operation(uint32_t op, Region& dst,
const Region& lhs,
const Region& rhs, int dx, int dy)
{
#if VALIDATE_REGIONS
validate(lhs, "boolean_operation (before): lhs");
validate(rhs, "boolean_operation (before): rhs");
validate(dst, "boolean_operation (before): dst");
#endif
size_t lhs_count;
Rect const * const lhs_rects = lhs.getArray(&lhs_count);
size_t rhs_count;
Rect const * const rhs_rects = rhs.getArray(&rhs_count);
region_operator<Rect>::region lhs_region(lhs_rects, lhs_count);
region_operator<Rect>::region rhs_region(rhs_rects, rhs_count, dx, dy);
region_operator<Rect> operation(op, lhs_region, rhs_region);
{ // scope for rasterizer (dtor has side effects)
rasterizer r(dst);
operation(r);
}
#if VALIDATE_REGIONS
validate(lhs, "boolean_operation: lhs");
validate(rhs, "boolean_operation: rhs");
validate(dst, "boolean_operation: dst");
#endif
#if VALIDATE_WITH_CORECG
SkRegion sk_lhs;
SkRegion sk_rhs;
SkRegion sk_dst;
for (size_t i=0 ; i<lhs_count ; i++)
sk_lhs.op(
lhs_rects[i].left + dx,
lhs_rects[i].top + dy,
lhs_rects[i].right + dx,
lhs_rects[i].bottom + dy,
SkRegion::kUnion_Op);
for (size_t i=0 ; i<rhs_count ; i++)
sk_rhs.op(
rhs_rects[i].left + dx,
rhs_rects[i].top + dy,
rhs_rects[i].right + dx,
rhs_rects[i].bottom + dy,
SkRegion::kUnion_Op);
const char* name = "---";
SkRegion::Op sk_op;
switch (op) {
case op_or: sk_op = SkRegion::kUnion_Op; name="OR"; break;
case op_xor: sk_op = SkRegion::kUnion_XOR; name="XOR"; break;
case op_and: sk_op = SkRegion::kIntersect_Op; name="AND"; break;
case op_nand: sk_op = SkRegion::kDifference_Op; name="NAND"; break;
}
sk_dst.op(sk_lhs, sk_rhs, sk_op);
if (sk_dst.isEmpty() && dst.isEmpty())
return;
bool same = true;
Region::const_iterator head = dst.begin();
Region::const_iterator const tail = dst.end();
SkRegion::Iterator it(sk_dst);
while (!it.done()) {
if (head != tail) {
if (
head->left != it.rect().fLeft ||
head->top != it.rect().fTop ||
head->right != it.rect().fRight ||
head->bottom != it.rect().fBottom
) {
same = false;
break;
}
} else {
same = false;
break;
}
head++;
it.next();
}
if (head != tail) {
same = false;
}
if(!same) {
ALOGD("---\nregion boolean %s failed", name);
lhs.dump("lhs");
rhs.dump("rhs");
dst.dump("dst");
ALOGD("should be");
SkRegion::Iterator it(sk_dst);
while (!it.done()) {
ALOGD(" [%3d, %3d, %3d, %3d]",
it.rect().fLeft,
it.rect().fTop,
it.rect().fRight,
it.rect().fBottom);
it.next();
}
}
#endif
}
void Region::boolean_operation(uint32_t op, Region& dst,
const Region& lhs,
const Rect& rhs, int dx, int dy)
{
// We allow this particular flavor of invalid Rect, since it is used as a
// signal value in various parts of the system
if (!rhs.isValid() && rhs != Rect::INVALID_RECT) {
ALOGE("Region::boolean_operation(op=%d) invalid Rect={%d,%d,%d,%d}",
op, rhs.left, rhs.top, rhs.right, rhs.bottom);
return;
}
#if VALIDATE_WITH_CORECG || VALIDATE_REGIONS
boolean_operation(op, dst, lhs, Region(rhs), dx, dy);
#else
size_t lhs_count;
Rect const * const lhs_rects = lhs.getArray(&lhs_count);
region_operator<Rect>::region lhs_region(lhs_rects, lhs_count);
region_operator<Rect>::region rhs_region(&rhs, 1, dx, dy);
region_operator<Rect> operation(op, lhs_region, rhs_region);
{ // scope for rasterizer (dtor has side effects)
rasterizer r(dst);
operation(r);
}
#endif
}
void Region::boolean_operation(uint32_t op, Region& dst,
const Region& lhs, const Region& rhs)
{
boolean_operation(op, dst, lhs, rhs, 0, 0);
}
void Region::boolean_operation(uint32_t op, Region& dst,
const Region& lhs, const Rect& rhs)
{
boolean_operation(op, dst, lhs, rhs, 0, 0);
}
void Region::translate(Region& reg, int dx, int dy)
{
if ((dx || dy) && !reg.isEmpty()) {
#if VALIDATE_REGIONS
validate(reg, "translate (before)");
#endif
size_t count = reg.mStorage.size();
Rect* rects = reg.mStorage.editArray();
while (count) {
rects->offsetBy(dx, dy);
rects++;
count--;
}
#if VALIDATE_REGIONS
validate(reg, "translate (after)");
#endif
}
}
void Region::translate(Region& dst, const Region& reg, int dx, int dy)
{
dst = reg;
translate(dst, dx, dy);
}
// ----------------------------------------------------------------------------
size_t Region::getFlattenedSize() const {
return sizeof(uint32_t) + mStorage.size() * sizeof(Rect);
}
status_t Region::flatten(void* buffer, size_t size) const {
#if VALIDATE_REGIONS
validate(*this, "Region::flatten");
#endif
if (size < getFlattenedSize()) {
return NO_MEMORY;
}
// Cast to uint32_t since the size of a size_t can vary between 32- and
// 64-bit processes
FlattenableUtils::write(buffer, size, static_cast<uint32_t>(mStorage.size()));
for (auto rect : mStorage) {
status_t result = rect.flatten(buffer, size);
if (result != NO_ERROR) {
return result;
}
FlattenableUtils::advance(buffer, size, sizeof(rect));
}
return NO_ERROR;
}
status_t Region::unflatten(void const* buffer, size_t size) {
if (size < sizeof(uint32_t)) {
return NO_MEMORY;
}
uint32_t numRects = 0;
FlattenableUtils::read(buffer, size, numRects);
if (size < numRects * sizeof(Rect)) {
return NO_MEMORY;
}
if (numRects > (UINT32_MAX / sizeof(Rect))) {
android_errorWriteWithInfoLog(0x534e4554, "29983260", -1, NULL, 0);
return NO_MEMORY;
}
Region result;
result.mStorage.clear();
for (size_t r = 0; r < numRects; ++r) {
Rect rect(Rect::EMPTY_RECT);
status_t status = rect.unflatten(buffer, size);
if (status != NO_ERROR) {
return status;
}
FlattenableUtils::advance(buffer, size, sizeof(rect));
result.mStorage.push_back(rect);
}
#if VALIDATE_REGIONS
validate(result, "Region::unflatten");
#endif
if (!result.validate(result, "Region::unflatten", true)) {
ALOGE("Region::unflatten() failed, invalid region");
return BAD_VALUE;
}
mStorage = result.mStorage;
return NO_ERROR;
}
// ----------------------------------------------------------------------------
Region::const_iterator Region::begin() const {
return mStorage.array();
}
Region::const_iterator Region::end() const {
size_t numRects = isRect() ? 1 : mStorage.size() - 1;
return mStorage.array() + numRects;
}
Rect const* Region::getArray(size_t* count) const {
if (count) *count = static_cast<size_t>(end() - begin());
return begin();
}
// ----------------------------------------------------------------------------
void Region::dump(String8& out, const char* what, uint32_t /* flags */) const
{
const_iterator head = begin();
const_iterator const tail = end();
out.appendFormat(" Region %s (this=%p, count=%" PRIdPTR ")\n",
what, this, tail - head);
while (head != tail) {
out.appendFormat(" [%3d, %3d, %3d, %3d]\n", head->left, head->top,
head->right, head->bottom);
++head;
}
}
void Region::dump(const char* what, uint32_t /* flags */) const
{
const_iterator head = begin();
const_iterator const tail = end();
ALOGD(" Region %s (this=%p, count=%" PRIdPTR ")\n", what, this, tail-head);
while (head != tail) {
ALOGD(" [%3d, %3d, %3d, %3d]\n",
head->left, head->top, head->right, head->bottom);
head++;
}
}
// ----------------------------------------------------------------------------
}; // namespace android