blob: b41d401aee323e0c8bd5ce4289d346e09b962d81 [file] [log] [blame]
/*
* Copyright 2015 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef GrTextBlobCache_DEFINED
#define GrTextBlobCache_DEFINED
#include "GrTextContext.h"
#include "SkMessageBus.h"
#include "SkRefCnt.h"
#include "SkTArray.h"
#include "SkTextBlobRunIterator.h"
#include "SkTHash.h"
class GrTextBlobCache {
public:
/**
* The callback function used by the cache when it is still over budget after a purge. The
* passed in 'data' is the same 'data' handed to setOverbudgetCallback.
*/
typedef void (*PFOverBudgetCB)(void* data);
GrTextBlobCache(PFOverBudgetCB cb, void* data, uint32_t uniqueID)
: fCallback(cb)
, fData(data)
, fSizeBudget(kDefaultBudget)
, fUniqueID(uniqueID)
, fPurgeBlobInbox(uniqueID) {
SkASSERT(cb && data);
}
~GrTextBlobCache();
// creates an uncached blob
sk_sp<GrTextBlob> makeBlob(int glyphCount, int runCount) {
return GrTextBlob::Make(glyphCount, runCount);
}
sk_sp<GrTextBlob> makeBlob(const SkTextBlob* blob) {
int glyphCount = 0;
int runCount = 0;
BlobGlyphCount(&glyphCount, &runCount, blob);
return GrTextBlob::Make(glyphCount, runCount);
}
sk_sp<GrTextBlob> makeCachedBlob(const SkTextBlob* blob,
const GrTextBlob::Key& key,
const SkMaskFilterBase::BlurRec& blurRec,
const SkPaint& paint) {
sk_sp<GrTextBlob> cacheBlob(this->makeBlob(blob));
cacheBlob->setupKey(key, blurRec, paint);
this->add(cacheBlob);
blob->notifyAddedToCache(fUniqueID);
return cacheBlob;
}
sk_sp<GrTextBlob> find(const GrTextBlob::Key& key) const {
const auto* idEntry = fBlobIDCache.find(key.fUniqueID);
return idEntry ? idEntry->find(key) : nullptr;
}
void remove(GrTextBlob* blob) {
auto id = GrTextBlob::GetKey(*blob).fUniqueID;
auto* idEntry = fBlobIDCache.find(id);
SkASSERT(idEntry);
fCurrentSize -= blob->size();
fBlobList.remove(blob);
idEntry->removeBlob(blob);
if (idEntry->fBlobs.empty()) {
fBlobIDCache.remove(id);
}
}
void makeMRU(GrTextBlob* blob) {
if (fBlobList.head() == blob) {
return;
}
fBlobList.remove(blob);
fBlobList.addToHead(blob);
}
void freeAll();
// TODO move to SkTextBlob
static void BlobGlyphCount(int* glyphCount, int* runCount, const SkTextBlob* blob) {
SkTextBlobRunIterator itCounter(blob);
for (; !itCounter.done(); itCounter.next(), (*runCount)++) {
*glyphCount += itCounter.glyphCount();
}
}
void setBudget(size_t budget) {
fSizeBudget = budget;
this->checkPurge();
}
struct PurgeBlobMessage {
uint32_t fID;
};
static void PostPurgeBlobMessage(uint32_t blobID, uint32_t cacheID);
void purgeStaleBlobs();
private:
using BitmapBlobList = SkTInternalLList<GrTextBlob>;
struct BlobIDCacheEntry {
BlobIDCacheEntry() : fID(SK_InvalidGenID) {}
explicit BlobIDCacheEntry(uint32_t id) : fID(id) {}
static uint32_t GetKey(const BlobIDCacheEntry& entry) {
return entry.fID;
}
void addBlob(sk_sp<GrTextBlob> blob) {
SkASSERT(blob);
SkASSERT(GrTextBlob::GetKey(*blob).fUniqueID == fID);
SkASSERT(!this->find(GrTextBlob::GetKey(*blob)));
fBlobs.emplace_back(std::move(blob));
}
void removeBlob(GrTextBlob* blob) {
SkASSERT(blob);
SkASSERT(GrTextBlob::GetKey(*blob).fUniqueID == fID);
auto index = this->findBlobIndex(GrTextBlob::GetKey(*blob));
SkASSERT(index >= 0);
fBlobs.removeShuffle(index);
}
sk_sp<GrTextBlob> find(const GrTextBlob::Key& key) const {
auto index = this->findBlobIndex(key);
return index < 0 ? nullptr : fBlobs[index];
}
int findBlobIndex(const GrTextBlob::Key& key) const{
for (int i = 0; i < fBlobs.count(); ++i) {
if (GrTextBlob::GetKey(*fBlobs[i]) == key) {
return i;
}
}
return -1;
}
uint32_t fID;
// Current clients don't generate multiple GrAtlasTextBlobs per SkTextBlob, so an array w/
// linear search is acceptable. If usage changes, we should re-evaluate this structure.
SkSTArray<1, sk_sp<GrTextBlob>, true> fBlobs;
};
void add(sk_sp<GrTextBlob> blob) {
auto id = GrTextBlob::GetKey(*blob).fUniqueID;
auto* idEntry = fBlobIDCache.find(id);
if (!idEntry) {
idEntry = fBlobIDCache.set(id, BlobIDCacheEntry(id));
}
// Safe to retain a raw ptr temporarily here, because the cache will hold a ref.
GrTextBlob* rawBlobPtr = blob.get();
fBlobList.addToHead(rawBlobPtr);
fCurrentSize += blob->size();
idEntry->addBlob(std::move(blob));
this->checkPurge(rawBlobPtr);
}
void checkPurge(GrTextBlob* blob = nullptr);
static const int kMinGrowthSize = 1 << 16;
static const int kDefaultBudget = 1 << 22;
BitmapBlobList fBlobList;
SkTHashMap<uint32_t, BlobIDCacheEntry> fBlobIDCache;
PFOverBudgetCB fCallback;
void* fData;
size_t fSizeBudget;
size_t fCurrentSize{0};
uint32_t fUniqueID; // unique id to use for messaging
SkMessageBus<PurgeBlobMessage>::Inbox fPurgeBlobInbox;
};
#endif