GrRingBuffer Class Reference

#include <GrRingBuffer.h>

Classes
struct	Slice

Public Member Functions
	GrRingBuffer (GrGpu *gpu, size_t size, size_t alignment, GrGpuBufferType intendedType)
Slice	suballocate (size_t size)
void	startSubmit (GrGpu *)
size_t	size () const

Detailed Description

A wrapper for a GPU buffer that allocates slices in a continuous ring.

It's assumed that suballocate and startSubmit are always called in the same thread, and that finishSubmit could be called in a separate thread.

Definition at line 23 of file GrRingBuffer.h.

Constructor & Destructor Documentation

GrRingBuffer()

GrRingBuffer::GrRingBuffer ( GrGpu *  gpu, size_t  size, size_t  alignment, GrGpuBufferType  intendedType  )

inline

Definition at line 25 of file GrRingBuffer.h.

        : fGpu(gpu)
        , fTotalSize(size)
        , fAlignment(alignment)
        , fType(intendedType)
        , fNewAllocation(false)
        , fHead(0)
        , fTail(0)
        , fGenID(0) {
        // We increment fHead and fTail without bound and let overflow handle any wrapping.
        // Because of this, size needs to be a power of two.
        SkASSERT(SkIsPow2(size));
    }

Member Function Documentation

size()

size_t GrRingBuffer::size ( ) const

inline

Definition at line 48 of file GrRingBuffer.h.

{ return fTotalSize; }

startSubmit()

void GrRingBuffer::startSubmit

(

GrGpu *

gpu

)

Definition at line 87 of file GrRingBuffer.cpp.

                                         {
    for (unsigned int i = 0; i < fPreviousBuffers.size(); ++i) {
        fPreviousBuffers[i]->unmap();
        gpu->takeOwnershipOfBuffer(std::move(fPreviousBuffers[i]));
    }
    fPreviousBuffers.clear();
 
    if (fNewAllocation) {
#ifdef SK_BUILD_FOR_MAC
        // Since we're using a Managed buffer on MacOS we need to unmap to write back to GPU
        // TODO: once we set up persistently mapped UPLOAD buffers on D3D, we can remove the
        // platform restriction.
        fCurrentBuffer->unmap();
#endif
        SubmitData* submitData = new SubmitData();
        submitData->fOwner = this;
        submitData->fLastHead = fHead;
        submitData->fGenID = fGenID;
        gpu->addFinishedProc(FinishSubmit, submitData);
        fNewAllocation = false;
    }
}

suballocate()

GrRingBuffer::Slice GrRingBuffer::suballocate

(

size_t

size

)

Definition at line 57 of file GrRingBuffer.cpp.

                                                       {
    fNewAllocation = true;
    if (fCurrentBuffer) {
        size_t offset = this->getAllocationOffset(size);
        if (offset < fTotalSize) {
            return { fCurrentBuffer.get(), offset };
        }
 
        // Try to grow allocation (old allocation will age out).
        fTotalSize *= 2;
        // Add current buffer to be tracked for next submit.
        fPreviousBuffers.push_back(std::move(fCurrentBuffer));
    }
 
    GrResourceProvider* resourceProvider = fGpu->getContext()->priv().resourceProvider();
    fCurrentBuffer = resourceProvider->createBuffer(fTotalSize,
                                                    fType,
                                                    kDynamic_GrAccessPattern,
                                                    GrResourceProvider::ZeroInit::kNo);
 
    SkASSERT(fCurrentBuffer);
    fHead = 0;
    fTail = 0;
    fGenID++;
    size_t offset = this->getAllocationOffset(size);
    SkASSERT(offset < fTotalSize);
    return { fCurrentBuffer.get(), offset };
}

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The documentation for this class was generated from the following files:

• third_party/skia/src/gpu/ganesh/GrRingBuffer.h
• third_party/skia/src/gpu/ganesh/GrRingBuffer.cpp