/*
* 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 GrOp_DEFINED
#define GrOp_DEFINED
#include "../private/SkAtomics.h"
#include "GrGpuResource.h"
#include "GrNonAtomicRef.h"
#include "GrXferProcessor.h"
#include "SkMatrix.h"
#include "SkRect.h"
#include "SkString.h"
#include <new>
class GrCaps;
class GrGpuCommandBuffer;
class GrOpFlushState;
/**
* GrOp is the base class for all Ganesh deferred GPU operations. To facilitate reordering and to
* minimize draw calls, Ganesh does not generate geometry inline with draw calls. Instead, it
* captures the arguments to the draw and then generates the geometry when flushing. This gives GrOp
* subclasses complete freedom to decide how/when to combine in order to produce fewer draw calls
* and minimize state changes.
*
* Ops of the same subclass may be merged using combineIfPossible. When two ops merge, one
* takes on the union of the data and the other is left empty. The merged op becomes responsible
* for drawing the data from both the original ops.
*
* If there are any possible optimizations which might require knowing more about the full state of
* the draw, e.g. whether or not the GrOp is allowed to tweak alpha for coverage, then this
* information will be communicated to the GrOp prior to geometry generation.
*
* The bounds of the op must contain all the vertices in device space *irrespective* of the clip.
* The bounds are used in determining which clip elements must be applied and thus the bounds cannot
* in turn depend upon the clip.
*/
#define GR_OP_SPEW 0
#if GR_OP_SPEW
#define GrOP_SPEW(code) code
#define GrOP_INFO(...) SkDebugf(__VA_ARGS__)
#else
#define GrOP_SPEW(code)
#define GrOP_INFO(...)
#endif
// A helper macro to generate a class static id
#define DEFINE_OP_CLASS_ID \
static uint32_t ClassID() { \
static uint32_t kClassID = GenOpClassID(); \
return kClassID; \
}
class GrOp : private SkNoncopyable {
public:
GrOp(uint32_t classID);
virtual ~GrOp();
virtual const char* name() const = 0;
bool combineIfPossible(GrOp* that, const GrCaps& caps) {
if (this->classID() != that->classID()) {
return false;
}
return this->onCombineIfPossible(that, caps);
}
const SkRect& bounds() const {
SkASSERT(kUninitialized_BoundsFlag != fBoundsFlags);
return fBounds;
}
void setClippedBounds(const SkRect& clippedBounds) {
fBounds = clippedBounds;
// The clipped bounds already incorporate any effect of the bounds flags.
fBoundsFlags = 0;
}
bool hasAABloat() const {
SkASSERT(fBoundsFlags != kUninitialized_BoundsFlag);
return SkToBool(fBoundsFlags & kAABloat_BoundsFlag);
}
bool hasZeroArea() const {
SkASSERT(fBoundsFlags != kUninitialized_BoundsFlag);
return SkToBool(fBoundsFlags & kZeroArea_BoundsFlag);
}
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 safely down-casting to a GrOp subclass
*/
template <typename T> const T& cast() const {
SkASSERT(T::ClassID() == this->classID());
return *static_cast<const T*>(this);
}
template <typename T> T* cast() {
SkASSERT(T::ClassID() == this->classID());
return static_cast<T*>(this);
}
uint32_t classID() const { SkASSERT(kIllegalOpID != fClassID); return fClassID; }
// We lazily initialize the uniqueID because currently the only user is GrAuditTrail
uint32_t uniqueID() const {
if (kIllegalOpID == fUniqueID) {
fUniqueID = GenOpID();
}
return fUniqueID;
}
/**
* This is called to notify the op that it has been recorded into a GrOpList. Ops can use this
* to begin preparations for the flush of the op list. Note that the op still may either be
* combined into another op or have another op combined into it via combineIfPossible() after
* this call is made.
*/
virtual void wasRecorded() {}
/**
* Called prior to executing. The op should perform any resource creation or data transfers
* necessary before execute() is called.
*/
void prepare(GrOpFlushState* state) { this->onPrepare(state); }
/** Issues the op's commands to GrGpu. */
void execute(GrOpFlushState* state) { this->onExecute(state); }
/** Used for spewing information about ops when debugging. */
virtual SkString dumpInfo() const {
SkString string;
string.appendf("OpBounds: [L: %.2f, T: %.2f, R: %.2f, B: %.2f]\n",
fBounds.fLeft, fBounds.fTop, fBounds.fRight, fBounds.fBottom);
return string;
}
protected:
/**
* Indicates that the op will produce geometry that extends beyond its bounds for the
* purpose of ensuring that the fragment shader runs on partially covered pixels for
* non-MSAA antialiasing.
*/
enum class HasAABloat {
kYes,
kNo
};
/**
* Indicates that the geometry represented by the op has zero area (e.g. it is hairline or
* points).
*/
enum class IsZeroArea {
kYes,
kNo
};
void setBounds(const SkRect& newBounds, HasAABloat aabloat, IsZeroArea zeroArea) {
fBounds = newBounds;
this->setBoundsFlags(aabloat, zeroArea);
}
void setTransformedBounds(const SkRect& srcBounds, const SkMatrix& m,
HasAABloat aabloat, IsZeroArea zeroArea) {
m.mapRect(&fBounds, srcBounds);
this->setBoundsFlags(aabloat, zeroArea);
}
void joinBounds(const GrOp& that) {
if (that.hasAABloat()) {
fBoundsFlags |= kAABloat_BoundsFlag;
}
if (that.hasZeroArea()) {
fBoundsFlags |= kZeroArea_BoundsFlag;
}
return fBounds.joinPossiblyEmptyRect(that.fBounds);
}
void replaceBounds(const GrOp& that) {
fBounds = that.fBounds;
fBoundsFlags = that.fBoundsFlags;
}
static uint32_t GenOpClassID() { return GenID(&gCurrOpClassID); }
private:
virtual bool onCombineIfPossible(GrOp*, const GrCaps& caps) = 0;
virtual void onPrepare(GrOpFlushState*) = 0;
virtual void onExecute(GrOpFlushState*) = 0;
static uint32_t GenID(int32_t* idCounter) {
// 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(idCounter)) + 1;
if (!id) {
SkFAIL("This should never wrap as it should only be called once for each GrOp "
"subclass.");
}
return id;
}
void setBoundsFlags(HasAABloat aabloat, IsZeroArea zeroArea) {
fBoundsFlags = 0;
fBoundsFlags |= (HasAABloat::kYes == aabloat) ? kAABloat_BoundsFlag : 0;
fBoundsFlags |= (IsZeroArea ::kYes == zeroArea) ? kZeroArea_BoundsFlag : 0;
}
enum {
kIllegalOpID = 0,
};
enum BoundsFlags {
kAABloat_BoundsFlag = 0x1,
kZeroArea_BoundsFlag = 0x2,
SkDEBUGCODE(kUninitialized_BoundsFlag = 0x4)
};
const uint16_t fClassID;
uint16_t fBoundsFlags;
static uint32_t GenOpID() { return GenID(&gCurrOpUniqueID); }
mutable uint32_t fUniqueID;
SkRect fBounds;
static int32_t gCurrOpUniqueID;
static int32_t gCurrOpClassID;
};
#endif