blob: 9b5db5e033912e36be0070babb40468b23563a89 [file] [log] [blame]
* Copyright 2012 Google Inc.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
#ifndef GrProcessor_DEFINED
#define GrProcessor_DEFINED
#include "GrColor.h"
#include "GrProcessorUnitTest.h"
#include "GrProgramElement.h"
#include "GrTextureAccess.h"
#include "SkMath.h"
#include "SkString.h"
class GrContext;
class GrCoordTransform;
class GrInvariantOutput;
* Used by processors to build their keys. It incorporates each per-processor key into a larger
* shader key.
class GrProcessorKeyBuilder {
GrProcessorKeyBuilder(SkTArray<unsigned char, true>* data) : fData(data), fCount(0) {
SkASSERT(0 == fData->count() % sizeof(uint32_t));
void add32(uint32_t v) {
fData->push_back_n(4, reinterpret_cast<uint8_t*>(&v));
/** Inserts count uint32_ts into the key. The returned pointer is only valid until the next
add*() call. */
uint32_t* SK_WARN_UNUSED_RESULT add32n(int count) {
SkASSERT(count > 0);
fCount += count;
return reinterpret_cast<uint32_t*>(fData->push_back_n(4 * count));
size_t size() const { return sizeof(uint32_t) * fCount; }
SkTArray<uint8_t, true>* fData; // unowned ptr to the larger key.
int fCount; // number of uint32_ts added to fData by the processor.
/** Provides custom shader code to the Ganesh shading pipeline. GrProcessor objects *must* be
immutable: after being constructed, their fields may not change.
Dynamically allocated GrProcessors are managed by a per-thread memory pool. The ref count of an
processor must reach 0 before the thread terminates and the pool is destroyed.
class GrProcessor : public GrProgramElement {
virtual ~GrProcessor();
/** Human-meaningful string to identify this prcoessor; may be embedded
in generated shader code. */
virtual const char* name() const = 0;
// Human-readable dump of all information
virtual SkString dumpInfo() const {
SkString str;
str.appendf("Missing data");
return str;
int numTextures() const { return fTextureAccesses.count(); }
/** Returns the access pattern for the texture at index. index must be valid according to
numTextures(). */
const GrTextureAccess& textureAccess(int index) const { return *fTextureAccesses[index]; }
/** Shortcut for textureAccess(index).texture(); */
GrTexture* texture(int index) const { return this->textureAccess(index).getTexture(); }
/** Will this processor read the fragment position? */
bool willReadFragmentPosition() const { return fWillReadFragmentPosition; }
void* operator new(size_t size);
void operator delete(void* target);
void* operator new(size_t size, void* placement) {
return ::operator new(size, placement);
void operator delete(void* target, void* placement) {
::operator delete(target, placement);
* Helper for down-casting to a GrProcessor subclass
template <typename T> const T& cast() const { return *static_cast<const T*>(this); }
uint32_t classID() const { SkASSERT(kIllegalProcessorClassID != fClassID); return fClassID; }
GrProcessor() : fClassID(kIllegalProcessorClassID), fWillReadFragmentPosition(false) {}
* Subclasses call this from their constructor to register GrTextureAccesses. The processor
* subclass manages the lifetime of the accesses (this function only stores a pointer). The
* GrTextureAccess is typically a member field of the GrProcessor subclass. This must only be
* called from the constructor because GrProcessors are immutable.
virtual void addTextureAccess(const GrTextureAccess* textureAccess);
bool hasSameTextureAccesses(const GrProcessor&) const;
* If the prcoessor will generate a backend-specific processor that will read the fragment
* position in the FS then it must call this method from its constructor. Otherwise, the
* request to access the fragment position will be denied.
void setWillReadFragmentPosition() { fWillReadFragmentPosition = true; }
template <typename PROC_SUBCLASS> void initClassID() {
static uint32_t kClassID = GenClassID();
fClassID = kClassID;
uint32_t fClassID;
SkSTArray<4, const GrTextureAccess*, true> fTextureAccesses;
static uint32_t GenClassID() {
// fCurrProcessorClassID has been initialized to kIllegalProcessorClassID. The
// atomic inc returns the old value not the incremented value. So we add
// 1 to the returned value.
uint32_t id = static_cast<uint32_t>(sk_atomic_inc(&gCurrProcessorClassID)) + 1;
if (!id) {
SkFAIL("This should never wrap as it should only be called once for each GrProcessor "
return id;
enum {
kIllegalProcessorClassID = 0,
static int32_t gCurrProcessorClassID;
bool fWillReadFragmentPosition;
typedef GrProgramElement INHERITED;