/*
* Copyright 2011 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef GrGpu_DEFINED
#define GrGpu_DEFINED
#include "GrDrawTarget.h"
#include "GrRect.h"
#include "GrRefCnt.h"
#include "GrTexture.h"
class GrContext;
class GrIndexBufferAllocPool;
class GrPathRenderer;
class GrPathRendererChain;
class GrResource;
class GrStencilBuffer;
class GrVertexBufferAllocPool;
/**
* Gpu usage statistics.
*/
struct GrGpuStats {
uint32_t fVertexCnt; //<! Number of vertices drawn
uint32_t fIndexCnt; //<! Number of indices drawn
uint32_t fDrawCnt; //<! Number of draws
uint32_t fProgChngCnt;//<! Number of program changes
/**
* Number of times the texture is set in 3D API
*/
uint32_t fTextureChngCnt;
/**
* Number of times the render target is set in 3D API
*/
uint32_t fRenderTargetChngCnt;
/**
* Number of textures created (includes textures that are rendertargets).
*/
uint32_t fTextureCreateCnt;
/**
* Number of rendertargets created.
*/
uint32_t fRenderTargetCreateCnt;
};
class GrGpu : public GrDrawTarget {
public:
/**
* Additional blend coeffecients for dual source blending, not exposed
* through GrPaint/GrContext.
*/
enum ExtendedBlendCoeffs {
// source 2 refers to second output color when
// using dual source blending.
kS2C_BlendCoeff = kPublicBlendCoeffCount,
kIS2C_BlendCoeff,
kS2A_BlendCoeff,
kIS2A_BlendCoeff,
kTotalBlendCoeffCount
};
/**
* Create an instance of GrGpu that matches the specified Engine backend.
* If the requested engine is not supported (at compile-time or run-time)
* this returns NULL.
*/
static GrGpu* Create(GrEngine, GrPlatform3DContext context3D);
////////////////////////////////////////////////////////////////////////////
GrGpu();
virtual ~GrGpu();
// The GrContext sets itself as the owner of this Gpu object
void setContext(GrContext* context) {
GrAssert(NULL == fContext);
fContext = context;
}
GrContext* getContext() { return fContext; }
const GrContext* getContext() const { return fContext; }
/**
* The GrGpu object normally assumes that no outsider is setting state
* within the underlying 3D API's context/device/whatever. This call informs
* the GrGpu that the state was modified and it shouldn't make assumptions
* about the state.
*/
void markContextDirty() { fContextIsDirty = true; }
void unimpl(const char[]);
/**
* Creates a texture object. If desc width or height is not a power of
* two but underlying API requires a power of two texture then srcData
* will be embedded in a power of two texture. The extra width and height
* is filled as though srcData were rendered clamped into the texture.
*
* If kRenderTarget_TextureFlag is specified the GrRenderTarget is
* accessible via GrTexture::asRenderTarget(). The texture will hold a ref
* on the render target until its releaseRenderTarget() is called or it is
* destroyed.
*
* @param desc describes the texture to be created.
* @param srcData texel data to load texture. Begins with full-size
* palette data for paletted textures. Contains width*
* height texels. If NULL texture data is uninitialized.
*
* @return The texture object if successful, otherwise NULL.
*/
GrTexture* createTexture(const GrTextureDesc& desc,
const void* srcData, size_t rowBytes);
/**
* Implements GrContext::createPlatformTexture
*/
GrTexture* createPlatformTexture(const GrPlatformTextureDesc& desc);
/**
* Implements GrContext::createPlatformTexture
*/
GrRenderTarget* createPlatformRenderTarget(const GrPlatformRenderTargetDesc& desc);
/**
* Creates a vertex buffer.
*
* @param size size in bytes of the vertex buffer
* @param dynamic hints whether the data will be frequently changed
* by either GrVertexBuffer::lock or
* GrVertexBuffer::updateData.
*
* @return The vertex buffer if successful, otherwise NULL.
*/
GrVertexBuffer* createVertexBuffer(uint32_t size, bool dynamic);
/**
* Creates an index buffer.
*
* @param size size in bytes of the index buffer
* @param dynamic hints whether the data will be frequently changed
* by either GrIndexBuffer::lock or
* GrIndexBuffer::updateData.
*
* @return The index buffer if successful, otherwise NULL.
*/
GrIndexBuffer* createIndexBuffer(uint32_t size, bool dynamic);
/**
* Returns an index buffer that can be used to render quads.
* Six indices per quad: 0, 1, 2, 0, 2, 3, etc.
* The max number of quads can be queried using GrIndexBuffer::maxQuads().
* Draw with kTriangles_PrimitiveType
* @ return the quad index buffer
*/
const GrIndexBuffer* getQuadIndexBuffer() const;
/**
* Returns a vertex buffer with four position-only vertices [(0,0), (1,0),
* (1,1), (0,1)].
* @ return unit square vertex buffer
*/
const GrVertexBuffer* getUnitSquareVertexBuffer() const;
/**
* Resolves MSAA.
*/
void resolveRenderTarget(GrRenderTarget* target);
/**
* Ensures that the current render target is actually set in the
* underlying 3D API. Used when client wants to use 3D API to directly
* render to the RT.
*/
void forceRenderTargetFlush();
/**
* If this returns true then a sequence that reads unpremultiplied pixels
* from a surface, writes back the same values, and reads them again will
* give the same pixel values back in both reads.
*/
virtual bool canPreserveReadWriteUnpremulPixels() = 0;
/**
* readPixels with some configs may be slow. Given a desired config this
* function returns a fast-path config. The returned config must have the
* same components, component sizes, and not require conversion between
* pre- and unpremultiplied alpha. The caller is free to ignore the result
* and call readPixels with the original config.
*/
virtual GrPixelConfig preferredReadPixelsConfig(GrPixelConfig config)
const {
return config;
}
/**
* Same as above but applies to writeTexturePixels
*/
virtual GrPixelConfig preferredWritePixelsConfig(GrPixelConfig config)
const {
return config;
}
/**
* OpenGL's readPixels returns the result bottom-to-top while the skia
* API is top-to-bottom. Thus we have to do a y-axis flip. The obvious
* solution is to have the subclass do the flip using either the CPU or GPU.
* However, the caller (GrContext) may have transformations to apply and can
* simply fold in the y-flip for free. On the other hand, the subclass may
* be able to do it for free itself. For example, the subclass may have to
* do memcpys to handle rowBytes that aren't tight. It could do the y-flip
* concurrently.
*
* This function returns true if a y-flip is required to put the pixels in
* top-to-bottom order and the subclass cannot do it for free.
*
* See read pixels for the params
* @return true if calling readPixels with the same set of params will
* produce bottom-to-top data
*/
virtual bool readPixelsWillPayForYFlip(GrRenderTarget* renderTarget,
int left, int top,
int width, int height,
GrPixelConfig config,
size_t rowBytes) const = 0;
/**
* This should return true if reading a NxM rectangle of pixels from a
* render target is faster if the target has dimensons N and M and the read
* rectangle has its top-left at 0,0.
*/
virtual bool fullReadPixelsIsFasterThanPartial() const { return false; };
/**
* Reads a rectangle of pixels from a render target. Fails if read requires
* conversion between premultiplied and unpremultiplied configs. The caller
* should do the conversion by rendering to a target with the desire config
* first.
*
* @param renderTarget the render target to read from. NULL means the
* current render target.
* @param left left edge of the rectangle to read (inclusive)
* @param top top edge of the rectangle to read (inclusive)
* @param width width of rectangle to read in pixels.
* @param height height of rectangle to read in pixels.
* @param config the pixel config of the destination buffer
* @param buffer memory to read the rectangle into.
* @param rowBytes the number of bytes between consecutive rows. Zero
* means rows are tightly packed.
* @param invertY buffer should be populated bottom-to-top as opposed
* to top-to-bottom (skia's usual order)
*
* @return true if the read succeeded, false if not. The read can fail
* because of a unsupported pixel config or because no render
* target is currently set.
*/
bool readPixels(GrRenderTarget* renderTarget,
int left, int top, int width, int height,
GrPixelConfig config, void* buffer, size_t rowBytes,
bool invertY);
/**
* Updates the pixels in a rectangle of a texture.
*
* @param left left edge of the rectangle to write (inclusive)
* @param top top edge of the rectangle to write (inclusive)
* @param width width of rectangle to write in pixels.
* @param height height of rectangle to write in pixels.
* @param config the pixel config of the source buffer
* @param buffer memory to read pixels from
* @param rowBytes number of bytes bewtween consecutive rows. Zero
* means rows are tightly packed.
*/
void writeTexturePixels(GrTexture* texture,
int left, int top, int width, int height,
GrPixelConfig config, const void* buffer,
size_t rowBytes);
const GrGpuStats& getStats() const;
void resetStats();
void printStats() const;
/**
* Called to tell Gpu object that all GrResources have been lost and should
* be abandoned. Overrides must call INHERITED::abandonResources().
*/
virtual void abandonResources();
/**
* Called to tell Gpu object to release all GrResources. Overrides must call
* INHERITED::releaseResources().
*/
void releaseResources();
/**
* Add resource to list of resources. Should only be called by GrResource.
* @param resource the resource to add.
*/
void insertResource(GrResource* resource);
/**
* Remove resource from list of resources. Should only be called by
* GrResource.
* @param resource the resource to remove.
*/
void removeResource(GrResource* resource);
// GrDrawTarget overrides
virtual void clear(const GrIRect* rect, GrColor color);
// After the client interacts directly with the 3D context state the GrGpu
// must resync its internal state and assumptions about 3D context state.
// Each time this occurs the GrGpu bumps a timestamp.
// state of the 3D context
// At 10 resets / frame and 60fps a 64bit timestamp will overflow in about
// a billion years.
typedef uint64_t ResetTimestamp;
// This timestamp is always older than the current timestamp
static const ResetTimestamp kExpiredTimestamp = 0;
// Returns a timestamp based on the number of times the context was reset.
// This timestamp can be used to lazily detect when cached 3D context state
// is dirty.
ResetTimestamp getResetTimestamp() const {
return fResetTimestamp;
}
protected:
enum PrivateDrawStateStateBits {
kFirstBit = (GrDrawState::kLastPublicStateBit << 1),
kModifyStencilClip_StateBit = kFirstBit, // allows draws to modify
// stencil bits used for
// clipping.
};
// keep track of whether we are using stencil clipping (as opposed to
// scissor).
bool fClipInStencil;
// prepares clip flushes gpu state before a draw
bool setupClipAndFlushState(GrPrimitiveType type);
// Functions used to map clip-respecting stencil tests into normal
// stencil funcs supported by GPUs.
static GrStencilFunc ConvertStencilFunc(bool stencilInClip,
GrStencilFunc func);
static void ConvertStencilFuncAndMask(GrStencilFunc func,
bool clipInStencil,
unsigned int clipBit,
unsigned int userBits,
unsigned int* ref,
unsigned int* mask);
// stencil settings to clip drawing when stencil clipping is in effect
// and the client isn't using the stencil test.
static const GrStencilSettings* GetClipStencilSettings();
GrGpuStats fStats;
struct GeometryPoolState {
const GrVertexBuffer* fPoolVertexBuffer;
int fPoolStartVertex;
const GrIndexBuffer* fPoolIndexBuffer;
int fPoolStartIndex;
};
const GeometryPoolState& getGeomPoolState() {
return fGeomPoolStateStack.back();
}
// GrDrawTarget overrides
virtual bool onReserveVertexSpace(GrVertexLayout vertexLayout,
int vertexCount,
void** vertices);
virtual bool onReserveIndexSpace(int indexCount, void** indices);
virtual void releaseReservedVertexSpace();
virtual void releaseReservedIndexSpace();
virtual void onSetVertexSourceToArray(const void* vertexArray,
int vertexCount);
virtual void onSetIndexSourceToArray(const void* indexArray,
int indexCount);
virtual void releaseVertexArray();
virtual void releaseIndexArray();
virtual void geometrySourceWillPush();
virtual void geometrySourceWillPop(const GeometrySrcState& restoredState);
// Helpers for setting up geometry state
void finalizeReservedVertices();
void finalizeReservedIndices();
// called when the 3D context state is unknown. Subclass should emit any
// assumed 3D context state and dirty any state cache
virtual void onResetContext() = 0;
// overridden by API-specific derived class to create objects.
virtual GrTexture* onCreateTexture(const GrTextureDesc& desc,
const void* srcData,
size_t rowBytes) = 0;
virtual GrTexture* onCreatePlatformTexture(const GrPlatformTextureDesc& desc) = 0;
virtual GrRenderTarget* onCreatePlatformRenderTarget(const GrPlatformRenderTargetDesc& desc) = 0;
virtual GrVertexBuffer* onCreateVertexBuffer(uint32_t size,
bool dynamic) = 0;
virtual GrIndexBuffer* onCreateIndexBuffer(uint32_t size,
bool dynamic) = 0;
// overridden by API-specific derivated class to perform the clear and
// clearRect. NULL rect means clear whole target.
virtual void onClear(const GrIRect* rect, GrColor color) = 0;
// overridden by API-specific derived class to perform the draw call.
virtual void onGpuDrawIndexed(GrPrimitiveType type,
uint32_t startVertex,
uint32_t startIndex,
uint32_t vertexCount,
uint32_t indexCount) = 0;
virtual void onGpuDrawNonIndexed(GrPrimitiveType type,
uint32_t vertexCount,
uint32_t numVertices) = 0;
// overridden by API-specific derived class to perform flush
virtual void onForceRenderTargetFlush() = 0;
// overridden by API-specific derived class to perform the read pixels.
virtual bool onReadPixels(GrRenderTarget* target,
int left, int top, int width, int height,
GrPixelConfig,
void* buffer,
size_t rowBytes,
bool invertY) = 0;
// overridden by API-specific derived class to perform the texture update
virtual void onWriteTexturePixels(GrTexture* texture,
int left, int top, int width, int height,
GrPixelConfig config, const void* buffer,
size_t rowBytes) = 0;
// overridden by API-specific derived class to perform the resolve
virtual void onResolveRenderTarget(GrRenderTarget* target) = 0;
// called to program the vertex data, indexCount will be 0 if drawing non-
// indexed geometry. The subclass may adjust the startVertex and/or
// startIndex since it may have already accounted for these in the setup.
virtual void setupGeometry(int* startVertex,
int* startIndex,
int vertexCount,
int indexCount) = 0;
// width and height may be larger than rt (if underlying API allows it).
// Should attach the SB to the RT. Returns false if compatible sb could
// not be created.
virtual bool createStencilBufferForRenderTarget(GrRenderTarget* rt,
int width,
int height) = 0;
// attaches an existing SB to an existing RT.
virtual bool attachStencilBufferToRenderTarget(GrStencilBuffer* sb,
GrRenderTarget* rt) = 0;
// The GrGpu typically records the clients requested state and then flushes
// deltas from previous state at draw time. This function does the
// API-specific flush of the state
// returns false if current state is unsupported.
virtual bool flushGraphicsState(GrPrimitiveType type) = 0;
// Sets the scissor rect, or disables if rect is NULL.
virtual void flushScissor(const GrIRect* rect) = 0;
// GrGpu subclass sets clip bit in the stencil buffer. The subclass is
// free to clear the remaining bits to zero if masked clears are more
// expensive than clearing all bits.
virtual void clearStencilClip(const GrIRect& rect, bool insideClip) = 0;
// clears the entire stencil buffer to 0
virtual void clearStencil() = 0;
private:
GrContext* fContext; // not reffed (context refs gpu)
ResetTimestamp fResetTimestamp;
GrVertexBufferAllocPool* fVertexPool;
GrIndexBufferAllocPool* fIndexPool;
// counts number of uses of vertex/index pool in the geometry stack
int fVertexPoolUseCnt;
int fIndexPoolUseCnt;
enum {
kPreallocGeomPoolStateStackCnt = 4,
};
SkSTArray<kPreallocGeomPoolStateStackCnt,
GeometryPoolState, true> fGeomPoolStateStack;
mutable GrIndexBuffer* fQuadIndexBuffer; // mutable so it can be
// created on-demand
mutable GrVertexBuffer* fUnitSquareVertexBuffer; // mutable so it can be
// created on-demand
// must be instantiated after GrGpu object has been given its owning
// GrContext ptr. (GrGpu is constructed first then handed off to GrContext).
GrPathRendererChain* fPathRendererChain;
bool fContextIsDirty;
GrResource* fResourceHead;
// Given a rt, find or create a stencil buffer and attach it
bool attachStencilBufferToRenderTarget(GrRenderTarget* target);
// GrDrawTarget overrides
virtual void onDrawIndexed(GrPrimitiveType type,
int startVertex,
int startIndex,
int vertexCount,
int indexCount);
virtual void onDrawNonIndexed(GrPrimitiveType type,
int startVertex,
int vertexCount);
// readies the pools to provide vertex/index data.
void prepareVertexPool();
void prepareIndexPool();
// determines the path renderer used to draw a clip path element.
GrPathRenderer* getClipPathRenderer(const SkPath& path, GrPathFill fill);
void resetContext() {
this->onResetContext();
++fResetTimestamp;
}
void handleDirtyContext() {
if (fContextIsDirty) {
this->resetContext();
fContextIsDirty = false;
}
}
typedef GrDrawTarget INHERITED;
};
#endif