/*
* Copyright 2014 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef GrResourceKey_DEFINED
#define GrResourceKey_DEFINED
#include "../private/SkOnce.h"
#include "../private/SkTemplates.h"
#include "GrTypes.h"
#include "SkData.h"
#include "SkString.h"
uint32_t GrResourceKeyHash(const uint32_t* data, size_t size);
/**
* Base class for all GrGpuResource cache keys. There are two types of cache keys. Refer to the
* comments for each key type below.
*/
class GrResourceKey {
public:
uint32_t hash() const {
this->validate();
return fKey[kHash_MetaDataIdx];
}
size_t size() const {
this->validate();
SkASSERT(this->isValid());
return this->internalSize();
}
protected:
static const uint32_t kInvalidDomain = 0;
GrResourceKey() { this->reset(); }
/** Reset to an invalid key. */
void reset() {
GR_STATIC_ASSERT((uint16_t)kInvalidDomain == kInvalidDomain);
fKey.reset(kMetaDataCnt);
fKey[kHash_MetaDataIdx] = 0;
fKey[kDomainAndSize_MetaDataIdx] = kInvalidDomain;
}
bool operator==(const GrResourceKey& that) const {
return this->hash() == that.hash() &&
0 == memcmp(&fKey[kHash_MetaDataIdx + 1],
&that.fKey[kHash_MetaDataIdx + 1],
this->internalSize() - sizeof(uint32_t));
}
GrResourceKey& operator=(const GrResourceKey& that) {
SkASSERT(that.isValid());
if (this != &that) {
size_t bytes = that.size();
SkASSERT(SkIsAlign4(bytes));
fKey.reset(SkToInt(bytes / sizeof(uint32_t)));
memcpy(fKey.get(), that.fKey.get(), bytes);
this->validate();
}
return *this;
}
bool isValid() const { return kInvalidDomain != this->domain(); }
uint32_t domain() const { return fKey[kDomainAndSize_MetaDataIdx] & 0xffff; }
/** size of the key data, excluding meta-data (hash, domain, etc). */
size_t dataSize() const { return this->size() - 4 * kMetaDataCnt; }
/** ptr to the key data, excluding meta-data (hash, domain, etc). */
const uint32_t* data() const {
this->validate();
return &fKey[kMetaDataCnt];
}
/** Used to initialize a key. */
class Builder {
public:
Builder(GrResourceKey* key, uint32_t domain, int data32Count) : fKey(key) {
SkASSERT(data32Count >= 0);
SkASSERT(domain != kInvalidDomain);
key->fKey.reset(kMetaDataCnt + data32Count);
int size = (data32Count + kMetaDataCnt) * sizeof(uint32_t);
SkASSERT(SkToU16(size) == size);
SkASSERT(SkToU16(domain) == domain);
key->fKey[kDomainAndSize_MetaDataIdx] = domain | (size << 16);
}
~Builder() { this->finish(); }
void finish() {
if (nullptr == fKey) {
return;
}
GR_STATIC_ASSERT(0 == kHash_MetaDataIdx);
uint32_t* hash = &fKey->fKey[kHash_MetaDataIdx];
*hash = GrResourceKeyHash(hash + 1, fKey->internalSize() - sizeof(uint32_t));
fKey->validate();
fKey = nullptr;
}
uint32_t& operator[](int dataIdx) {
SkASSERT(fKey);
SkDEBUGCODE(size_t dataCount = fKey->internalSize() / sizeof(uint32_t) - kMetaDataCnt;)
SkASSERT(SkToU32(dataIdx) < dataCount);
return fKey->fKey[kMetaDataCnt + dataIdx];
}
private:
GrResourceKey* fKey;
};
private:
enum MetaDataIdx {
kHash_MetaDataIdx,
// The key domain and size are packed into a single uint32_t.
kDomainAndSize_MetaDataIdx,
kLastMetaDataIdx = kDomainAndSize_MetaDataIdx
};
static const uint32_t kMetaDataCnt = kLastMetaDataIdx + 1;
size_t internalSize() const {
return fKey[kDomainAndSize_MetaDataIdx] >> 16;
}
void validate() const {
SkASSERT(fKey[kHash_MetaDataIdx] ==
GrResourceKeyHash(&fKey[kHash_MetaDataIdx] + 1,
this->internalSize() - sizeof(uint32_t)));
SkASSERT(SkIsAlign4(this->internalSize()));
}
friend class TestResource; // For unit test to access kMetaDataCnt.
// bmp textures require 7 uint32_t values (5 for the base key, and two more for image
// cacherator's decode format.
SkAutoSTMalloc<kMetaDataCnt + 7, uint32_t> fKey;
};
/**
* A key used for scratch resources. There are three important rules about scratch keys:
* * Multiple resources can share the same scratch key. Therefore resources assigned the same
* scratch key should be interchangeable with respect to the code that uses them.
* * A resource can have at most one scratch key and it is set at resource creation by the
* resource itself.
* * When a scratch resource is ref'ed it will not be returned from the
* cache for a subsequent cache request until all refs are released. This facilitates using
* a scratch key for multiple render-to-texture scenarios. An example is a separable blur:
*
* GrTexture* texture[2];
* texture[0] = get_scratch_texture(scratchKey);
* texture[1] = get_scratch_texture(scratchKey); // texture[0] is already owned so we will get a
* // different one for texture[1]
* draw_mask(texture[0], path); // draws path mask to texture[0]
* blur_x(texture[0], texture[1]); // blurs texture[0] in y and stores result in texture[1]
* blur_y(texture[1], texture[0]); // blurs texture[1] in y and stores result in texture[0]
* texture[1]->unref(); // texture 1 can now be recycled for the next request with scratchKey
* consume_blur(texture[0]);
* texture[0]->unref(); // texture 0 can now be recycled for the next request with scratchKey
*/
class GrScratchKey : public GrResourceKey {
private:
typedef GrResourceKey INHERITED;
public:
/** Uniquely identifies the type of resource that is cached as scratch. */
typedef uint32_t ResourceType;
/** Generate a unique ResourceType. */
static ResourceType GenerateResourceType();
/** Creates an invalid scratch key. It must be initialized using a Builder object before use. */
GrScratchKey() {}
GrScratchKey(const GrScratchKey& that) { *this = that; }
/** reset() returns the key to the invalid state. */
using INHERITED::reset;
using INHERITED::isValid;
ResourceType resourceType() const { return this->domain(); }
GrScratchKey& operator=(const GrScratchKey& that) {
this->INHERITED::operator=(that);
return *this;
}
bool operator==(const GrScratchKey& that) const {
return this->INHERITED::operator==(that);
}
bool operator!=(const GrScratchKey& that) const { return !(*this == that); }
class Builder : public INHERITED::Builder {
public:
Builder(GrScratchKey* key, ResourceType type, int data32Count)
: INHERITED::Builder(key, type, data32Count) {}
};
};
/**
* A key that allows for exclusive use of a resource for a use case (AKA "domain"). There are three
* rules governing the use of unique keys:
* * Only one resource can have a given unique key at a time. Hence, "unique".
* * A resource can have at most one unique key at a time.
* * Unlike scratch keys, multiple requests for a unique key will return the same
* resource even if the resource already has refs.
* This key type allows a code path to create cached resources for which it is the exclusive user.
* The code path creates a domain which it sets on its keys. This guarantees that there are no
* cross-domain collisions.
*
* Unique keys preempt scratch keys. While a resource has a unique key it is inaccessible via its
* scratch key. It can become scratch again if the unique key is removed.
*/
class GrUniqueKey : public GrResourceKey {
private:
typedef GrResourceKey INHERITED;
public:
typedef uint32_t Domain;
/** Generate a Domain for unique keys. */
static Domain GenerateDomain();
/** Creates an invalid unique key. It must be initialized using a Builder object before use. */
GrUniqueKey() {}
GrUniqueKey(const GrUniqueKey& that) { *this = that; }
/** reset() returns the key to the invalid state. */
using INHERITED::reset;
using INHERITED::isValid;
GrUniqueKey& operator=(const GrUniqueKey& that) {
this->INHERITED::operator=(that);
this->setCustomData(sk_ref_sp(that.getCustomData()));
SkDEBUGCODE(fTag = that.fTag;)
return *this;
}
bool operator==(const GrUniqueKey& that) const {
return this->INHERITED::operator==(that);
}
bool operator!=(const GrUniqueKey& that) const { return !(*this == that); }
void setCustomData(sk_sp<SkData> data) {
fData = std::move(data);
}
SkData* getCustomData() const {
return fData.get();
}
SkDEBUGCODE(const char* tag() const { return fTag.c_str(); })
class Builder : public INHERITED::Builder {
public:
Builder(GrUniqueKey* key, Domain type, int data32Count, const char* tag = nullptr)
: INHERITED::Builder(key, type, data32Count) {
SkDEBUGCODE(key->fTag = tag;)
(void) tag; // suppress unused named param warning.
}
/** Used to build a key that wraps another key and adds additional data. */
Builder(GrUniqueKey* key, const GrUniqueKey& innerKey, Domain domain, int extraData32Cnt,
const char* tag = nullptr)
: INHERITED::Builder(key, domain, Data32CntForInnerKey(innerKey) + extraData32Cnt) {
SkASSERT(&innerKey != key);
// add the inner key to the end of the key so that op[] can be indexed normally.
uint32_t* innerKeyData = &this->operator[](extraData32Cnt);
const uint32_t* srcData = innerKey.data();
(*innerKeyData++) = innerKey.domain();
memcpy(innerKeyData, srcData, innerKey.dataSize());
SkDEBUGCODE(key->fTag = tag;)
(void) tag; // suppress unused named param warning.
}
private:
static int Data32CntForInnerKey(const GrUniqueKey& innerKey) {
// key data + domain
return SkToInt((innerKey.dataSize() >> 2) + 1);
}
};
private:
sk_sp<SkData> fData;
SkDEBUGCODE(SkString fTag;)
};
/**
* It is common to need a frequently reused GrUniqueKey where the only requirement is that the key
* is unique. These macros create such a key in a thread safe manner so the key can be truly global
* and only constructed once.
*/
/** Place outside of function/class definitions. */
#define GR_DECLARE_STATIC_UNIQUE_KEY(name) static SkOnce name##_once
/** Place inside function where the key is used. */
#define GR_DEFINE_STATIC_UNIQUE_KEY(name) \
static SkAlignedSTStorage<1, GrUniqueKey> name##_storage; \
name##_once(gr_init_static_unique_key_once, &name##_storage); \
static const GrUniqueKey& name = *reinterpret_cast<GrUniqueKey*>(name##_storage.get());
static inline void gr_init_static_unique_key_once(SkAlignedSTStorage<1,GrUniqueKey>* keyStorage) {
GrUniqueKey* key = new (keyStorage->get()) GrUniqueKey;
GrUniqueKey::Builder builder(key, GrUniqueKey::GenerateDomain(), 0);
}
// The cache listens for these messages to purge junk resources proactively.
class GrUniqueKeyInvalidatedMessage {
public:
explicit GrUniqueKeyInvalidatedMessage(const GrUniqueKey& key) : fKey(key) {}
GrUniqueKeyInvalidatedMessage(const GrUniqueKeyInvalidatedMessage& that) : fKey(that.fKey) {}
GrUniqueKeyInvalidatedMessage& operator=(const GrUniqueKeyInvalidatedMessage& that) {
fKey = that.fKey;
return *this;
}
const GrUniqueKey& key() const { return fKey; }
private:
GrUniqueKey fKey;
};
#endif