src/gpu/gl/GrGLBufferImpl.cpp - platform/external/skia - Gitiles

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */

 #include "GrGLBufferImpl.h"
 #include "GrGpuGL.h"

 #define GL_CALL(GPU, X) GR_GL_CALL(GPU->glInterface(), X)

 #ifdef SK_DEBUG
 #define VALIDATE() this->validate()
 #else
 #define VALIDATE() do {} while(false)
 #endif

 // GL_STREAM_DRAW triggers an optimization in Chromium's GPU process where a client's vertex buffer
 // objects are implemented as client-side-arrays on tile-deferred architectures.
 #define DYNAMIC_USAGE_PARAM GR_GL_STREAM_DRAW

 GrGLBufferImpl::GrGLBufferImpl(GrGpuGL* gpu, const Desc& desc, GrGLenum bufferType)
     : fDesc(desc)
     , fBufferType(bufferType)
     , fMapPtr(NULL) {
     if (0 == desc.fID) {
         fCPUData = sk_malloc_flags(desc.fSizeInBytes, SK_MALLOC_THROW);
         fGLSizeInBytes = 0;
     } else {
         fCPUData = NULL;
         // We assume that the GL buffer was created at the desc's size initially.
         fGLSizeInBytes = fDesc.fSizeInBytes;
     }
     VALIDATE();
 }

 void GrGLBufferImpl::release(GrGpuGL* gpu) {
     VALIDATE();
     // make sure we've not been abandoned or already released
     if (fCPUData) {
         sk_free(fCPUData);
         fCPUData = NULL;
     } else if (fDesc.fID && !fDesc.fIsWrapped) {
         GL_CALL(gpu, DeleteBuffers(1, &fDesc.fID));
         if (GR_GL_ARRAY_BUFFER == fBufferType) {
             gpu->notifyVertexBufferDelete(fDesc.fID);
         } else {
             SkASSERT(GR_GL_ELEMENT_ARRAY_BUFFER == fBufferType);
             gpu->notifyIndexBufferDelete(fDesc.fID);
         }
         fDesc.fID = 0;
         fGLSizeInBytes = 0;
     }
     fMapPtr = NULL;
     VALIDATE();
 }

 void GrGLBufferImpl::abandon() {
     fDesc.fID = 0;
     fGLSizeInBytes = 0;
     fMapPtr = NULL;
     sk_free(fCPUData);
     fCPUData = NULL;
     VALIDATE();
 }

 void GrGLBufferImpl::bind(GrGpuGL* gpu) const {
     VALIDATE();
     if (GR_GL_ARRAY_BUFFER == fBufferType) {
         gpu->bindVertexBuffer(fDesc.fID);
     } else {
         SkASSERT(GR_GL_ELEMENT_ARRAY_BUFFER == fBufferType);
         gpu->bindIndexBufferAndDefaultVertexArray(fDesc.fID);
     }
     VALIDATE();
 }

 void* GrGLBufferImpl::map(GrGpuGL* gpu) {
     VALIDATE();
     SkASSERT(!this->isMapped());
     if (0 == fDesc.fID) {
         fMapPtr = fCPUData;
     } else {
         switch (gpu->glCaps().mapBufferType()) {
             case GrGLCaps::kNone_MapBufferType:
                 VALIDATE();
                 return NULL;
             case GrGLCaps::kMapBuffer_MapBufferType:
                 this->bind(gpu);
                 // Let driver know it can discard the old data
                 if (GR_GL_USE_BUFFER_DATA_NULL_HINT || fDesc.fSizeInBytes != fGLSizeInBytes) {
                     fGLSizeInBytes = fDesc.fSizeInBytes;
                     GL_CALL(gpu,
                             BufferData(fBufferType, fGLSizeInBytes, NULL,
                                        fDesc.fDynamic ? DYNAMIC_USAGE_PARAM : GR_GL_STATIC_DRAW));
                 }
                 GR_GL_CALL_RET(gpu->glInterface(), fMapPtr,
                                MapBuffer(fBufferType, GR_GL_WRITE_ONLY));
                 break;
             case GrGLCaps::kMapBufferRange_MapBufferType: {
                 this->bind(gpu);
                 // Make sure the GL buffer size agrees with fDesc before mapping.
                 if (fDesc.fSizeInBytes != fGLSizeInBytes) {
                     fGLSizeInBytes = fDesc.fSizeInBytes;
                     GL_CALL(gpu,
                             BufferData(fBufferType, fGLSizeInBytes, NULL,
                                        fDesc.fDynamic ? DYNAMIC_USAGE_PARAM : GR_GL_STATIC_DRAW));
                 }
                 static const GrGLbitfield kAccess = GR_GL_MAP_INVALIDATE_BUFFER_BIT |
                                                     GR_GL_MAP_WRITE_BIT;
                 GR_GL_CALL_RET(gpu->glInterface(),
                                fMapPtr,
                                MapBufferRange(fBufferType, 0, fGLSizeInBytes, kAccess));
                 break;
             }
             case GrGLCaps::kChromium_MapBufferType:
                 this->bind(gpu);
                 // Make sure the GL buffer size agrees with fDesc before mapping.
                 if (fDesc.fSizeInBytes != fGLSizeInBytes) {
                     fGLSizeInBytes = fDesc.fSizeInBytes;
                     GL_CALL(gpu,
                             BufferData(fBufferType, fGLSizeInBytes, NULL,
                                        fDesc.fDynamic ? DYNAMIC_USAGE_PARAM : GR_GL_STATIC_DRAW));
                 }
                 GR_GL_CALL_RET(gpu->glInterface(),
                                fMapPtr,
                                MapBufferSubData(fBufferType, 0, fGLSizeInBytes, GR_GL_WRITE_ONLY));
                 break;
         }
     }
     VALIDATE();
     return fMapPtr;
 }

 void GrGLBufferImpl::unmap(GrGpuGL* gpu) {
     VALIDATE();
     SkASSERT(this->isMapped());
     if (0 != fDesc.fID) {
         switch (gpu->glCaps().mapBufferType()) {
             case GrGLCaps::kNone_MapBufferType:
                 SkDEBUGFAIL("Shouldn't get here.");
                 return;
             case GrGLCaps::kMapBuffer_MapBufferType: // fall through
             case GrGLCaps::kMapBufferRange_MapBufferType:
                 this->bind(gpu);
                 GL_CALL(gpu, UnmapBuffer(fBufferType));
                 break;
             case GrGLCaps::kChromium_MapBufferType:
                 this->bind(gpu);
                 GR_GL_CALL(gpu->glInterface(), UnmapBufferSubData(fMapPtr));
                 break;
         }
     }
     fMapPtr = NULL;
 }

 bool GrGLBufferImpl::isMapped() const {
     VALIDATE();
     return SkToBool(fMapPtr);
 }

 bool GrGLBufferImpl::updateData(GrGpuGL* gpu, const void* src, size_t srcSizeInBytes) {
     SkASSERT(!this->isMapped());
     VALIDATE();
     if (srcSizeInBytes > fDesc.fSizeInBytes) {
         return false;
     }
     if (0 == fDesc.fID) {
         memcpy(fCPUData, src, srcSizeInBytes);
         return true;
     }
     this->bind(gpu);
     GrGLenum usage = fDesc.fDynamic ? DYNAMIC_USAGE_PARAM : GR_GL_STATIC_DRAW;

 #if GR_GL_USE_BUFFER_DATA_NULL_HINT
     if (fDesc.fSizeInBytes == srcSizeInBytes) {
         GL_CALL(gpu, BufferData(fBufferType, (GrGLsizeiptr) srcSizeInBytes, src, usage));
     } else {
         // Before we call glBufferSubData we give the driver a hint using
         // glBufferData with NULL. This makes the old buffer contents
         // inaccessible to future draws. The GPU may still be processing
         // draws that reference the old contents. With this hint it can
         // assign a different allocation for the new contents to avoid
         // flushing the gpu past draws consuming the old contents.
         fGLSizeInBytes = fDesc.fSizeInBytes;
         GL_CALL(gpu, BufferData(fBufferType, fGLSizeInBytes, NULL, usage));
         GL_CALL(gpu, BufferSubData(fBufferType, 0, (GrGLsizeiptr) srcSizeInBytes, src));
     }
 #else
     // Note that we're cheating on the size here. Currently no methods
     // allow a partial update that preserves contents of non-updated
     // portions of the buffer (map() does a glBufferData(..size, NULL..))
     bool doSubData = false;
 #if GR_GL_MAC_BUFFER_OBJECT_PERFOMANCE_WORKAROUND
     static int N = 0;
     // 128 was chosen experimentally. At 256 a slight hitchiness was noticed
     // when dragging a Chromium window around with a canvas tab backgrounded.
     doSubData = 0 == (N % 128);
     ++N;
 #endif
     if (doSubData) {
         // The workaround is to do a glBufferData followed by glBufferSubData.
         // Chromium's command buffer may turn a glBufferSubData where the size
         // exactly matches the buffer size into a glBufferData. So we tack 1
         // extra byte onto the glBufferData.
         fGLSizeInBytes = srcSizeInBytes + 1;
         GL_CALL(gpu, BufferData(fBufferType, fGLSizeInBytes, NULL, usage));
         GL_CALL(gpu, BufferSubData(fBufferType, 0, srcSizeInBytes, src));
     } else {
         fGLSizeInBytes = srcSizeInBytes;
         GL_CALL(gpu, BufferData(fBufferType, fGLSizeInBytes, src, usage));
     }
 #endif
     return true;
 }

 void GrGLBufferImpl::validate() const {
     SkASSERT(GR_GL_ARRAY_BUFFER == fBufferType || GR_GL_ELEMENT_ARRAY_BUFFER == fBufferType);
     // The following assert isn't valid when the buffer has been abandoned:
     // SkASSERT((0 == fDesc.fID) == (fCPUData));
     SkASSERT(0 != fDesc.fID || !fDesc.fIsWrapped);
     SkASSERT(NULL == fCPUData || 0 == fGLSizeInBytes);
     SkASSERT(NULL == fMapPtr || fCPUData || fGLSizeInBytes == fDesc.fSizeInBytes);
     SkASSERT(NULL == fCPUData || NULL == fMapPtr || fCPUData == fMapPtr);
 }
	/*
	* Copyright 2013 Google Inc.
	*
	* Use of this source code is governed by a BSD-style license that can be
	* found in the LICENSE file.
	*/

	#include "GrGLBufferImpl.h"
	#include "GrGpuGL.h"

	#define GL_CALL(GPU, X) GR_GL_CALL(GPU->glInterface(), X)

	#ifdef SK_DEBUG
	#define VALIDATE() this->validate()
	#else
	#define VALIDATE() do {} while(false)
	#endif

	// GL_STREAM_DRAW triggers an optimization in Chromium's GPU process where a client's vertex buffer
	// objects are implemented as client-side-arrays on tile-deferred architectures.
	#define DYNAMIC_USAGE_PARAM GR_GL_STREAM_DRAW

	GrGLBufferImpl::GrGLBufferImpl(GrGpuGL* gpu, const Desc& desc, GrGLenum bufferType)
	: fDesc(desc)
	, fBufferType(bufferType)
	, fMapPtr(NULL) {
	if (0 == desc.fID) {
	fCPUData = sk_malloc_flags(desc.fSizeInBytes, SK_MALLOC_THROW);
	fGLSizeInBytes = 0;
	} else {
	fCPUData = NULL;
	// We assume that the GL buffer was created at the desc's size initially.
	fGLSizeInBytes = fDesc.fSizeInBytes;
	}
	VALIDATE();
	}

	void GrGLBufferImpl::release(GrGpuGL* gpu) {
	VALIDATE();
	// make sure we've not been abandoned or already released
	if (fCPUData) {
	sk_free(fCPUData);
	fCPUData = NULL;
	} else if (fDesc.fID && !fDesc.fIsWrapped) {
	GL_CALL(gpu, DeleteBuffers(1, &fDesc.fID));
	if (GR_GL_ARRAY_BUFFER == fBufferType) {
	gpu->notifyVertexBufferDelete(fDesc.fID);
	} else {
	SkASSERT(GR_GL_ELEMENT_ARRAY_BUFFER == fBufferType);
	gpu->notifyIndexBufferDelete(fDesc.fID);
	}
	fDesc.fID = 0;
	fGLSizeInBytes = 0;
	}
	fMapPtr = NULL;
	VALIDATE();
	}

	void GrGLBufferImpl::abandon() {
	fDesc.fID = 0;
	fGLSizeInBytes = 0;
	fMapPtr = NULL;
	sk_free(fCPUData);
	fCPUData = NULL;
	VALIDATE();
	}

	void GrGLBufferImpl::bind(GrGpuGL* gpu) const {
	VALIDATE();
	if (GR_GL_ARRAY_BUFFER == fBufferType) {
	gpu->bindVertexBuffer(fDesc.fID);
	} else {
	SkASSERT(GR_GL_ELEMENT_ARRAY_BUFFER == fBufferType);
	gpu->bindIndexBufferAndDefaultVertexArray(fDesc.fID);
	}
	VALIDATE();
	}

	void* GrGLBufferImpl::map(GrGpuGL* gpu) {
	VALIDATE();
	SkASSERT(!this->isMapped());
	if (0 == fDesc.fID) {
	fMapPtr = fCPUData;
	} else {
	switch (gpu->glCaps().mapBufferType()) {
	case GrGLCaps::kNone_MapBufferType:
	VALIDATE();
	return NULL;
	case GrGLCaps::kMapBuffer_MapBufferType:
	this->bind(gpu);
	// Let driver know it can discard the old data
	if (GR_GL_USE_BUFFER_DATA_NULL_HINT \|\| fDesc.fSizeInBytes != fGLSizeInBytes) {
	fGLSizeInBytes = fDesc.fSizeInBytes;
	GL_CALL(gpu,
	BufferData(fBufferType, fGLSizeInBytes, NULL,
	fDesc.fDynamic ? DYNAMIC_USAGE_PARAM : GR_GL_STATIC_DRAW));
	}
	GR_GL_CALL_RET(gpu->glInterface(), fMapPtr,
	MapBuffer(fBufferType, GR_GL_WRITE_ONLY));
	break;
	case GrGLCaps::kMapBufferRange_MapBufferType: {
	this->bind(gpu);
	// Make sure the GL buffer size agrees with fDesc before mapping.
	if (fDesc.fSizeInBytes != fGLSizeInBytes) {
	fGLSizeInBytes = fDesc.fSizeInBytes;
	GL_CALL(gpu,
	BufferData(fBufferType, fGLSizeInBytes, NULL,
	fDesc.fDynamic ? DYNAMIC_USAGE_PARAM : GR_GL_STATIC_DRAW));
	}
	static const GrGLbitfield kAccess = GR_GL_MAP_INVALIDATE_BUFFER_BIT \|
	GR_GL_MAP_WRITE_BIT;
	GR_GL_CALL_RET(gpu->glInterface(),
	fMapPtr,
	MapBufferRange(fBufferType, 0, fGLSizeInBytes, kAccess));
	break;
	}
	case GrGLCaps::kChromium_MapBufferType:
	this->bind(gpu);
	// Make sure the GL buffer size agrees with fDesc before mapping.
	if (fDesc.fSizeInBytes != fGLSizeInBytes) {
	fGLSizeInBytes = fDesc.fSizeInBytes;
	GL_CALL(gpu,
	BufferData(fBufferType, fGLSizeInBytes, NULL,
	fDesc.fDynamic ? DYNAMIC_USAGE_PARAM : GR_GL_STATIC_DRAW));
	}
	GR_GL_CALL_RET(gpu->glInterface(),
	fMapPtr,
	MapBufferSubData(fBufferType, 0, fGLSizeInBytes, GR_GL_WRITE_ONLY));
	break;
	}
	}
	VALIDATE();
	return fMapPtr;
	}

	void GrGLBufferImpl::unmap(GrGpuGL* gpu) {
	VALIDATE();
	SkASSERT(this->isMapped());
	if (0 != fDesc.fID) {
	switch (gpu->glCaps().mapBufferType()) {
	case GrGLCaps::kNone_MapBufferType:
	SkDEBUGFAIL("Shouldn't get here.");
	return;
	case GrGLCaps::kMapBuffer_MapBufferType: // fall through
	case GrGLCaps::kMapBufferRange_MapBufferType:
	this->bind(gpu);
	GL_CALL(gpu, UnmapBuffer(fBufferType));
	break;
	case GrGLCaps::kChromium_MapBufferType:
	this->bind(gpu);
	GR_GL_CALL(gpu->glInterface(), UnmapBufferSubData(fMapPtr));
	break;
	}
	}
	fMapPtr = NULL;
	}

	bool GrGLBufferImpl::isMapped() const {
	VALIDATE();
	return SkToBool(fMapPtr);
	}

	bool GrGLBufferImpl::updateData(GrGpuGL* gpu, const void* src, size_t srcSizeInBytes) {
	SkASSERT(!this->isMapped());
	VALIDATE();
	if (srcSizeInBytes > fDesc.fSizeInBytes) {
	return false;
	}
	if (0 == fDesc.fID) {
	memcpy(fCPUData, src, srcSizeInBytes);
	return true;
	}
	this->bind(gpu);
	GrGLenum usage = fDesc.fDynamic ? DYNAMIC_USAGE_PARAM : GR_GL_STATIC_DRAW;

	#if GR_GL_USE_BUFFER_DATA_NULL_HINT
	if (fDesc.fSizeInBytes == srcSizeInBytes) {
	GL_CALL(gpu, BufferData(fBufferType, (GrGLsizeiptr) srcSizeInBytes, src, usage));
	} else {
	// Before we call glBufferSubData we give the driver a hint using
	// glBufferData with NULL. This makes the old buffer contents
	// inaccessible to future draws. The GPU may still be processing
	// draws that reference the old contents. With this hint it can
	// assign a different allocation for the new contents to avoid
	// flushing the gpu past draws consuming the old contents.
	fGLSizeInBytes = fDesc.fSizeInBytes;
	GL_CALL(gpu, BufferData(fBufferType, fGLSizeInBytes, NULL, usage));
	GL_CALL(gpu, BufferSubData(fBufferType, 0, (GrGLsizeiptr) srcSizeInBytes, src));
	}
	#else
	// Note that we're cheating on the size here. Currently no methods
	// allow a partial update that preserves contents of non-updated
	// portions of the buffer (map() does a glBufferData(..size, NULL..))
	bool doSubData = false;
	#if GR_GL_MAC_BUFFER_OBJECT_PERFOMANCE_WORKAROUND
	static int N = 0;
	// 128 was chosen experimentally. At 256 a slight hitchiness was noticed
	// when dragging a Chromium window around with a canvas tab backgrounded.
	doSubData = 0 == (N % 128);
	++N;
	#endif
	if (doSubData) {
	// The workaround is to do a glBufferData followed by glBufferSubData.
	// Chromium's command buffer may turn a glBufferSubData where the size
	// exactly matches the buffer size into a glBufferData. So we tack 1
	// extra byte onto the glBufferData.
	fGLSizeInBytes = srcSizeInBytes + 1;
	GL_CALL(gpu, BufferData(fBufferType, fGLSizeInBytes, NULL, usage));
	GL_CALL(gpu, BufferSubData(fBufferType, 0, srcSizeInBytes, src));
	} else {
	fGLSizeInBytes = srcSizeInBytes;
	GL_CALL(gpu, BufferData(fBufferType, fGLSizeInBytes, src, usage));
	}
	#endif
	return true;
	}

	void GrGLBufferImpl::validate() const {
	SkASSERT(GR_GL_ARRAY_BUFFER == fBufferType \|\| GR_GL_ELEMENT_ARRAY_BUFFER == fBufferType);
	// The following assert isn't valid when the buffer has been abandoned:
	// SkASSERT((0 == fDesc.fID) == (fCPUData));
	SkASSERT(0 != fDesc.fID \|\| !fDesc.fIsWrapped);
	SkASSERT(NULL == fCPUData \|\| 0 == fGLSizeInBytes);
	SkASSERT(NULL == fMapPtr \|\| fCPUData \|\| fGLSizeInBytes == fDesc.fSizeInBytes);
	SkASSERT(NULL == fCPUData \|\| NULL == fMapPtr \|\| fCPUData == fMapPtr);
	}