/*
* Copyright 2010 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef GrDrawTarget_DEFINED
#define GrDrawTarget_DEFINED
#include "GrClipData.h"
#include "GrContext.h"
#include "GrDrawState.h"
#include "GrIndexBuffer.h"
#include "GrTraceMarker.h"
#include "SkClipStack.h"
#include "SkMatrix.h"
#include "SkPath.h"
#include "SkStrokeRec.h"
#include "SkTArray.h"
#include "SkTLazy.h"
#include "SkTypes.h"
#include "SkXfermode.h"
class GrClipData;
class GrDrawTargetCaps;
class GrPath;
class GrVertexBuffer;
class GrDrawTarget : public SkRefCnt {
protected:
class DrawInfo;
public:
SK_DECLARE_INST_COUNT(GrDrawTarget)
///////////////////////////////////////////////////////////////////////////
// The context may not be fully constructed and should not be used during GrDrawTarget
// construction.
GrDrawTarget(GrContext* context);
virtual ~GrDrawTarget();
/**
* Gets the capabilities of the draw target.
*/
const GrDrawTargetCaps* caps() const { return fCaps.get(); }
/**
* Sets the current clip to the region specified by clip. All draws will be
* clipped against this clip if kClip_StateBit is enabled.
*
* Setting the clip may (or may not) zero out the client's stencil bits.
*
* @param description of the clipping region
*/
void setClip(const GrClipData* clip);
/**
* Gets the current clip.
*
* @return the clip.
*/
const GrClipData* getClip() const;
/**
* Sets the draw state object for the draw target. Note that this does not
* make a copy. The GrDrawTarget will take a reference to passed object.
* Passing NULL will cause the GrDrawTarget to use its own internal draw
* state object rather than an externally provided one.
*/
void setDrawState(GrDrawState* drawState);
/**
* Read-only access to the GrDrawTarget's current draw state.
*/
const GrDrawState& getDrawState() const { return *fDrawState; }
/**
* Read-write access to the GrDrawTarget's current draw state. Note that
* this doesn't ref.
*/
GrDrawState* drawState() { return fDrawState; }
/**
* Color alpha and coverage are two inputs to the drawing pipeline. For some
* blend modes it is safe to fold the coverage into constant or per-vertex
* color alpha value. For other blend modes they must be handled separately.
* Depending on features available in the underlying 3D API this may or may
* not be possible.
*
* This function considers the current draw state and the draw target's
* capabilities to determine whether coverage can be handled correctly. The
* following assumptions are made:
* 1. The caller intends to somehow specify coverage. This can be
* specified either by enabling a coverage stage on the GrDrawState or
* via the vertex layout.
* 2. Other than enabling coverage stages or enabling coverage in the
* layout, the current configuration of the target's GrDrawState is as
* it will be at draw time.
*/
bool canApplyCoverage() const;
/** When we're using coverage AA but the blend is incompatible (given gpu
* limitations) we should disable AA. */
bool shouldDisableCoverageAAForBlend() {
// Enable below if we should draw with AA even when it produces
// incorrect blending.
// return false;
return !this->canApplyCoverage();
}
/**
* Given the current draw state and hw support, will HW AA lines be used (if
* a line primitive type is drawn)?
*/
bool willUseHWAALines() const;
/**
* There are three types of "sources" of geometry (vertices and indices) for
* draw calls made on the target. When performing an indexed draw, the
* indices and vertices can use different source types. Once a source is
* specified it can be used for multiple draws. However, the time at which
* the geometry data is no longer editable depends on the source type.
*
* Sometimes it is necessary to perform a draw while upstack code has
* already specified geometry that it isn't finished with. So there are push
* and pop methods. This allows the client to push the sources, draw
* something using alternate sources, and then pop to restore the original
* sources.
*
* Aside from pushes and pops, a source remains valid until another source
* is set or resetVertexSource / resetIndexSource is called. Drawing from
* a reset source is an error.
*
* The three types of sources are:
*
* 1. A cpu array (set*SourceToArray). This is useful when the caller
* already provided vertex data in a format compatible with a
* GrVertexLayout. The data in the array is consumed at the time that
* set*SourceToArray is called and subsequent edits to the array will not
* be reflected in draws.
*
* 2. Reserve. This is most useful when the caller has data it must
* transform before drawing and is not long-lived. The caller requests
* that the draw target make room for some amount of vertex and/or index
* data. The target provides ptrs to hold the vertex and/or index data.
*
* The data is writable up until the next drawIndexed, drawNonIndexed,
* drawIndexedInstances, drawRect, copySurface, or pushGeometrySource. At
* this point the data is frozen and the ptrs are no longer valid.
*
* Where the space is allocated and how it is uploaded to the GPU is
* subclass-dependent.
*
* 3. Vertex and Index Buffers. This is most useful for geometry that will
* is long-lived. When the data in the buffer is consumed depends on the
* GrDrawTarget subclass. For deferred subclasses the caller has to
* guarantee that the data is still available in the buffers at playback.
* (TODO: Make this more automatic as we have done for read/write pixels)
*
* The size of each vertex is determined by querying the current GrDrawState.
*/
/**
* Reserves space for vertices and/or indices. Zero can be specifed as
* either the vertex or index count if the caller desires to only reserve
* space for only indices or only vertices. If zero is specifed for
* vertexCount then the vertex source will be unmodified and likewise for
* indexCount.
*
* If the function returns true then the reserve suceeded and the vertices
* and indices pointers will point to the space created.
*
* If the target cannot make space for the request then this function will
* return false. If vertexCount was non-zero then upon failure the vertex
* source is reset and likewise for indexCount.
*
* The pointers to the space allocated for vertices and indices remain valid
* until a drawIndexed, drawNonIndexed, drawIndexedInstances, drawRect,
* copySurface, or push/popGeomtrySource is called. At that point logically a
* snapshot of the data is made and the pointers are invalid.
*
* @param vertexCount the number of vertices to reserve space for. Can be
* 0. Vertex size is queried from the current GrDrawState.
* @param indexCount the number of indices to reserve space for. Can be 0.
* @param vertices will point to reserved vertex space if vertexCount is
* non-zero. Illegal to pass NULL if vertexCount > 0.
* @param indices will point to reserved index space if indexCount is
* non-zero. Illegal to pass NULL if indexCount > 0.
*/
bool reserveVertexAndIndexSpace(int vertexCount,
int indexCount,
void** vertices,
void** indices);
/**
* Provides hints to caller about the number of vertices and indices
* that can be allocated cheaply. This can be useful if caller is reserving
* space but doesn't know exactly how much geometry is needed.
*
* Also may hint whether the draw target should be flushed first. This is
* useful for deferred targets.
*
* @param vertexCount in: hint about how many vertices the caller would
* like to allocate. Vertex size is queried from the
* current GrDrawState.
* out: a hint about the number of vertices that can be
* allocated cheaply. Negative means no hint.
* Ignored if NULL.
* @param indexCount in: hint about how many indices the caller would
* like to allocate.
* out: a hint about the number of indices that can be
* allocated cheaply. Negative means no hint.
* Ignored if NULL.
*
* @return true if target should be flushed based on the input values.
*/
virtual bool geometryHints(int* vertexCount,
int* indexCount) const;
/**
* Sets source of vertex data for the next draw. Array must contain
* the vertex data when this is called.
*
* @param vertexArray cpu array containing vertex data.
* @param vertexCount the number of vertices in the array. Vertex size is
* queried from the current GrDrawState.
*/
void setVertexSourceToArray(const void* vertexArray, int vertexCount);
/**
* Sets source of index data for the next indexed draw. Array must contain
* the indices when this is called.
*
* @param indexArray cpu array containing index data.
* @param indexCount the number of indices in the array.
*/
void setIndexSourceToArray(const void* indexArray, int indexCount);
/**
* Sets source of vertex data for the next draw. Data does not have to be
* in the buffer until drawIndexed, drawNonIndexed, or drawIndexedInstances.
*
* @param buffer vertex buffer containing vertex data. Must be
* unlocked before draw call. Vertex size is queried
* from current GrDrawState.
*/
void setVertexSourceToBuffer(const GrVertexBuffer* buffer);
/**
* Sets source of index data for the next indexed draw. Data does not have
* to be in the buffer until drawIndexed.
*
* @param buffer index buffer containing indices. Must be unlocked
* before indexed draw call.
*/
void setIndexSourceToBuffer(const GrIndexBuffer* buffer);
/**
* Resets vertex source. Drawing from reset vertices is illegal. Set vertex
* source to reserved, array, or buffer before next draw. May be able to free
* up temporary storage allocated by setVertexSourceToArray or
* reserveVertexSpace.
*/
void resetVertexSource();
/**
* Resets index source. Indexed Drawing from reset indices is illegal. Set
* index source to reserved, array, or buffer before next indexed draw. May
* be able to free up temporary storage allocated by setIndexSourceToArray
* or reserveIndexSpace.
*/
void resetIndexSource();
/**
* Query to find out if the vertex or index source is reserved.
*/
bool hasReservedVerticesOrIndices() const {
return kReserved_GeometrySrcType == this->getGeomSrc().fVertexSrc ||
kReserved_GeometrySrcType == this->getGeomSrc().fIndexSrc;
}
/**
* Pushes and resets the vertex/index sources. Any reserved vertex / index
* data is finalized (i.e. cannot be updated after the matching pop but can
* be drawn from). Must be balanced by a pop.
*/
void pushGeometrySource();
/**
* Pops the vertex / index sources from the matching push.
*/
void popGeometrySource();
/**
* Draws indexed geometry using the current state and current vertex / index
* sources.
*
* @param type The type of primitives to draw.
* @param startVertex the vertex in the vertex array/buffer corresponding
* to index 0
* @param startIndex first index to read from index src.
* @param vertexCount one greater than the max index.
* @param indexCount the number of index elements to read. The index count
* is effectively trimmed to the last completely
* specified primitive.
* @param devBounds optional bounds hint. This is a promise from the caller,
* not a request for clipping.
*/
void drawIndexed(GrPrimitiveType type,
int startVertex,
int startIndex,
int vertexCount,
int indexCount,
const SkRect* devBounds = NULL);
/**
* Draws non-indexed geometry using the current state and current vertex
* sources.
*
* @param type The type of primitives to draw.
* @param startVertex the vertex in the vertex array/buffer corresponding
* to index 0
* @param vertexCount one greater than the max index.
* @param devBounds optional bounds hint. This is a promise from the caller,
* not a request for clipping.
*/
void drawNonIndexed(GrPrimitiveType type,
int startVertex,
int vertexCount,
const SkRect* devBounds = NULL);
/**
* Draws path into the stencil buffer. The fill must be either even/odd or
* winding (not inverse or hairline). It will respect the HW antialias flag
* on the draw state (if possible in the 3D API).
*/
void stencilPath(const GrPath*, SkPath::FillType fill);
/**
* Draws a path. Fill must not be a hairline. It will respect the HW
* antialias flag on the draw state (if possible in the 3D API).
*/
void drawPath(const GrPath*, SkPath::FillType fill);
/**
* Draws many paths. It will respect the HW
* antialias flag on the draw state (if possible in the 3D API).
*
* @param transforms array of 2d affine transformations, one for each path.
* @param fill the fill type for drawing all the paths. Fill must not be a
* hairline.
* @param stroke the stroke for drawing all the paths.
*/
void drawPaths(int pathCount, const GrPath** paths,
const SkMatrix* transforms, SkPath::FillType fill,
SkStrokeRec::Style stroke);
/**
* Helper function for drawing rects. It performs a geometry src push and pop
* and thus will finalize any reserved geometry.
*
* @param rect the rect to draw
* @param matrix optional matrix applied to rect (before viewMatrix)
* @param localRect optional rect that specifies local coords to map onto
* rect. If NULL then rect serves as the local coords.
* @param localMatrix optional matrix applied to localRect. If
* srcRect is non-NULL and srcMatrix is non-NULL
* then srcRect will be transformed by srcMatrix.
* srcMatrix can be NULL when no srcMatrix is desired.
*/
void drawRect(const SkRect& rect,
const SkMatrix* matrix,
const SkRect* localRect,
const SkMatrix* localMatrix) {
AutoGeometryPush agp(this);
this->onDrawRect(rect, matrix, localRect, localMatrix);
}
/**
* Helper for drawRect when the caller doesn't need separate local rects or matrices.
*/
void drawSimpleRect(const SkRect& rect, const SkMatrix* matrix = NULL) {
this->drawRect(rect, matrix, NULL, NULL);
}
void drawSimpleRect(const SkIRect& irect, const SkMatrix* matrix = NULL) {
SkRect rect = SkRect::Make(irect);
this->drawRect(rect, matrix, NULL, NULL);
}
/**
* This call is used to draw multiple instances of some geometry with a
* given number of vertices (V) and indices (I) per-instance. The indices in
* the index source must have the form i[k+I] == i[k] + V. Also, all indices
* i[kI] ... i[(k+1)I-1] must be elements of the range kV ... (k+1)V-1. As a
* concrete example, the following index buffer for drawing a series of
* quads each as two triangles each satisfies these conditions with V=4 and
* I=6:
* (0,1,2,0,2,3, 4,5,6,4,6,7, 8,9,10,8,10,11, ...)
*
* The call assumes that the pattern of indices fills the entire index
* source. The size of the index buffer limits the number of instances that
* can be drawn by the GPU in a single draw. However, the caller may specify
* any (positive) number for instanceCount and if necessary multiple GPU
* draws will be issued. Moreover, when drawIndexedInstances is called
* multiple times it may be possible for GrDrawTarget to group them into a
* single GPU draw.
*
* @param type the type of primitives to draw
* @param instanceCount the number of instances to draw. Each instance
* consists of verticesPerInstance vertices indexed by
* indicesPerInstance indices drawn as the primitive
* type specified by type.
* @param verticesPerInstance The number of vertices in each instance (V
* in the above description).
* @param indicesPerInstance The number of indices in each instance (I
* in the above description).
* @param devBounds optional bounds hint. This is a promise from the caller,
* not a request for clipping.
*/
void drawIndexedInstances(GrPrimitiveType type,
int instanceCount,
int verticesPerInstance,
int indicesPerInstance,
const SkRect* devBounds = NULL);
/**
* Clear the current render target if one isn't passed in. Ignores the
* clip and all other draw state (blend mode, stages, etc). Clears the
* whole thing if rect is NULL, otherwise just the rect. If canIgnoreRect
* is set then the entire render target can be optionally cleared.
*/
virtual void clear(const SkIRect* rect,
GrColor color,
bool canIgnoreRect,
GrRenderTarget* renderTarget = NULL) = 0;
/**
* Discards the contents render target. NULL indicates that the current render target should
* be discarded.
**/
virtual void discard(GrRenderTarget* = NULL) = 0;
/**
* Called at start and end of gpu trace marking
* GR_CREATE_GPU_TRACE_MARKER(marker_str, target) will automatically call these at the start
* and end of a code block respectively
*/
void addGpuTraceMarker(const GrGpuTraceMarker* marker);
void removeGpuTraceMarker(const GrGpuTraceMarker* marker);
/**
* Takes the current active set of markers and stores them for later use. Any current marker
* in the active set is removed from the active set and the targets remove function is called.
* These functions do not work as a stack so you cannot call save a second time before calling
* restore. Also, it is assumed that when restore is called the current active set of markers
* is empty. When the stored markers are added back into the active set, the targets add marker
* is called.
*/
void saveActiveTraceMarkers();
void restoreActiveTraceMarkers();
/**
* Copies a pixel rectangle from one surface to another. This call may finalize
* reserved vertex/index data (as though a draw call was made). The src pixels
* copied are specified by srcRect. They are copied to a rect of the same
* size in dst with top left at dstPoint. If the src rect is clipped by the
* src bounds then pixel values in the dst rect corresponding to area clipped
* by the src rect are not overwritten. This method can fail and return false
* depending on the type of surface, configs, etc, and the backend-specific
* limitations. If rect is clipped out entirely by the src or dst bounds then
* true is returned since there is no actual copy necessary to succeed.
*/
bool copySurface(GrSurface* dst,
GrSurface* src,
const SkIRect& srcRect,
const SkIPoint& dstPoint);
/**
* Function that determines whether a copySurface call would succeed without
* performing the copy.
*/
bool canCopySurface(GrSurface* dst,
GrSurface* src,
const SkIRect& srcRect,
const SkIPoint& dstPoint);
/**
* This is can be called before allocating a texture to be a dst for copySurface. It will
* populate the origin, config, and flags fields of the desc such that copySurface is more
* likely to succeed and be efficient.
*/
virtual void initCopySurfaceDstDesc(const GrSurface* src, GrTextureDesc* desc);
/**
* Release any resources that are cached but not currently in use. This
* is intended to give an application some recourse when resources are low.
*/
virtual void purgeResources() {};
/**
* For subclass internal use to invoke a call to onDraw(). See DrawInfo below.
*/
void executeDraw(const DrawInfo& info) { this->onDraw(info); }
/**
* For subclass internal use to invoke a call to onDrawPath().
*/
void executeDrawPath(const GrPath* path, SkPath::FillType fill,
const GrDeviceCoordTexture* dstCopy) {
this->onDrawPath(path, fill, dstCopy);
}
/**
* For subclass internal use to invoke a call to onDrawPaths().
*/
void executeDrawPaths(int pathCount, const GrPath** paths,
const SkMatrix* transforms, SkPath::FillType fill,
SkStrokeRec::Style stroke,
const GrDeviceCoordTexture* dstCopy) {
this->onDrawPaths(pathCount, paths, transforms, fill, stroke, dstCopy);
}
inline bool isGpuTracingEnabled() const {
return this->getContext()->isGpuTracingEnabled();
}
////////////////////////////////////////////////////////////////////////////
/**
* See AutoStateRestore below.
*/
enum ASRInit {
kPreserve_ASRInit,
kReset_ASRInit
};
/**
* Saves off the current state and restores it in the destructor. It will
* install a new GrDrawState object on the target (setDrawState) and restore
* the previous one in the destructor. The caller should call drawState() to
* get the new draw state after the ASR is installed.
*
* GrDrawState* state = target->drawState();
* AutoStateRestore asr(target, GrDrawTarget::kReset_ASRInit).
* state->setRenderTarget(rt); // state refers to the GrDrawState set on
* // target before asr was initialized.
* // Therefore, rt is set on the GrDrawState
* // that will be restored after asr's
* // destructor rather than target's current
* // GrDrawState.
*/
class AutoStateRestore : public ::SkNoncopyable {
public:
/**
* Default ASR will have no effect unless set() is subsequently called.
*/
AutoStateRestore();
/**
* Saves the state on target. The state will be restored when the ASR
* is destroyed. If this constructor is used do not call set().
*
* @param init Should the newly installed GrDrawState be a copy of the
* previous state or a default-initialized GrDrawState.
* @param viewMatrix Optional view matrix. If init = kPreserve then the draw state's
* matrix will be preconcat'ed with the param. All stages will be
updated to compensate for the matrix change. If init == kReset
then the draw state's matrix will be this matrix.
*/
AutoStateRestore(GrDrawTarget* target, ASRInit init, const SkMatrix* viewMatrix = NULL);
~AutoStateRestore();
/**
* Saves the state on target. The state will be restored when the ASR
* is destroyed. This should only be called once per ASR object and only
* when the default constructor was used. For nested saves use multiple
* ASR objects.
*
* @param init Should the newly installed GrDrawState be a copy of the
* previous state or a default-initialized GrDrawState.
* @param viewMatrix Optional view matrix. If init = kPreserve then the draw state's
* matrix will be preconcat'ed with the param. All stages will be
updated to compensate for the matrix change. If init == kReset
then the draw state's matrix will be this matrix.
*/
void set(GrDrawTarget* target, ASRInit init, const SkMatrix* viewMatrix = NULL);
/**
* Like set() but makes the view matrix identity. When init is kReset it is as though
* NULL was passed to set's viewMatrix param. When init is kPreserve it is as though
* the inverse view matrix was passed. If kPreserve is passed and the draw state's matrix
* is not invertible then this may fail.
*/
bool setIdentity(GrDrawTarget* target, ASRInit init);
private:
GrDrawTarget* fDrawTarget;
SkTLazy<GrDrawState> fTempState;
GrDrawState* fSavedState;
};
////////////////////////////////////////////////////////////////////////////
class AutoReleaseGeometry : public ::SkNoncopyable {
public:
AutoReleaseGeometry(GrDrawTarget* target,
int vertexCount,
int indexCount);
AutoReleaseGeometry();
~AutoReleaseGeometry();
bool set(GrDrawTarget* target,
int vertexCount,
int indexCount);
bool succeeded() const { return NULL != fTarget; }
void* vertices() const { SkASSERT(this->succeeded()); return fVertices; }
void* indices() const { SkASSERT(this->succeeded()); return fIndices; }
SkPoint* positions() const {
return static_cast<SkPoint*>(this->vertices());
}
private:
void reset();
GrDrawTarget* fTarget;
void* fVertices;
void* fIndices;
};
////////////////////////////////////////////////////////////////////////////
class AutoClipRestore : public ::SkNoncopyable {
public:
AutoClipRestore(GrDrawTarget* target) {
fTarget = target;
fClip = fTarget->getClip();
}
AutoClipRestore(GrDrawTarget* target, const SkIRect& newClip);
~AutoClipRestore() {
fTarget->setClip(fClip);
}
private:
GrDrawTarget* fTarget;
const GrClipData* fClip;
SkTLazy<SkClipStack> fStack;
GrClipData fReplacementClip;
};
////////////////////////////////////////////////////////////////////////////
/**
* Saves the geometry src state at construction and restores in the destructor. It also saves
* and then restores the vertex attrib state.
*/
class AutoGeometryPush : public ::SkNoncopyable {
public:
AutoGeometryPush(GrDrawTarget* target)
: fAttribRestore(target->drawState()) {
SkASSERT(NULL != target);
fTarget = target;
target->pushGeometrySource();
}
~AutoGeometryPush() { fTarget->popGeometrySource(); }
private:
GrDrawTarget* fTarget;
GrDrawState::AutoVertexAttribRestore fAttribRestore;
};
/**
* Combination of AutoGeometryPush and AutoStateRestore. The vertex attribs will be in default
* state regardless of ASRInit value.
*/
class AutoGeometryAndStatePush : public ::SkNoncopyable {
public:
AutoGeometryAndStatePush(GrDrawTarget* target,
ASRInit init,
const SkMatrix* viewMatrix = NULL)
: fState(target, init, viewMatrix) {
SkASSERT(NULL != target);
fTarget = target;
target->pushGeometrySource();
if (kPreserve_ASRInit == init) {
target->drawState()->setDefaultVertexAttribs();
}
}
~AutoGeometryAndStatePush() { fTarget->popGeometrySource(); }
private:
AutoStateRestore fState;
GrDrawTarget* fTarget;
};
///////////////////////////////////////////////////////////////////////////
// Draw execution tracking (for font atlases and other resources)
class DrawToken {
public:
DrawToken(GrDrawTarget* drawTarget, uint32_t drawID) :
fDrawTarget(drawTarget), fDrawID(drawID) {}
bool isIssued() { return NULL != fDrawTarget && fDrawTarget->isIssued(fDrawID); }
private:
GrDrawTarget* fDrawTarget;
uint32_t fDrawID; // this may wrap, but we're doing direct comparison
// so that should be okay
};
virtual DrawToken getCurrentDrawToken() { return DrawToken(this, 0); }
protected:
enum GeometrySrcType {
kNone_GeometrySrcType, //<! src has not been specified
kReserved_GeometrySrcType, //<! src was set using reserve*Space
kArray_GeometrySrcType, //<! src was set using set*SourceToArray
kBuffer_GeometrySrcType //<! src was set using set*SourceToBuffer
};
struct GeometrySrcState {
GeometrySrcType fVertexSrc;
union {
// valid if src type is buffer
const GrVertexBuffer* fVertexBuffer;
// valid if src type is reserved or array
int fVertexCount;
};
GeometrySrcType fIndexSrc;
union {
// valid if src type is buffer
const GrIndexBuffer* fIndexBuffer;
// valid if src type is reserved or array
int fIndexCount;
};
size_t fVertexSize;
};
int indexCountInCurrentSource() const {
const GeometrySrcState& src = this->getGeomSrc();
switch (src.fIndexSrc) {
case kNone_GeometrySrcType:
return 0;
case kReserved_GeometrySrcType:
case kArray_GeometrySrcType:
return src.fIndexCount;
case kBuffer_GeometrySrcType:
return static_cast<int>(src.fIndexBuffer->gpuMemorySize() / sizeof(uint16_t));
default:
SkFAIL("Unexpected Index Source.");
return 0;
}
}
// This method is called by copySurface The srcRect is guaranteed to be entirely within the
// src bounds. Likewise, the dst rect implied by dstPoint and srcRect's width and height falls
// entirely within the dst. The default implementation will draw a rect from the src to the
// dst if the src is a texture and the dst is a render target and fail otherwise.
virtual bool onCopySurface(GrSurface* dst,
GrSurface* src,
const SkIRect& srcRect,
const SkIPoint& dstPoint);
// Called to determine whether an onCopySurface call would succeed or not. This is useful for
// proxy subclasses to test whether the copy would succeed without executing it yet. Derived
// classes must keep this consistent with their implementation of onCopySurface(). The inputs
// are the same as onCopySurface(), i.e. srcRect and dstPoint are clipped to be inside the src
// and dst bounds.
virtual bool onCanCopySurface(GrSurface* dst,
GrSurface* src,
const SkIRect& srcRect,
const SkIPoint& dstPoint);
GrContext* getContext() { return fContext; }
const GrContext* getContext() const { return fContext; }
// A subclass may override this function if it wishes to be notified when the clip is changed.
// The override should call INHERITED::clipWillBeSet().
virtual void clipWillBeSet(const GrClipData* clipData);
// subclasses must call this in their destructors to ensure all vertex
// and index sources have been released (including those held by
// pushGeometrySource())
void releaseGeometry();
// accessors for derived classes
const GeometrySrcState& getGeomSrc() const { return fGeoSrcStateStack.back(); }
// it is preferable to call this rather than getGeomSrc()->fVertexSize because of the assert.
size_t getVertexSize() const {
// the vertex layout is only valid if a vertex source has been specified.
SkASSERT(this->getGeomSrc().fVertexSrc != kNone_GeometrySrcType);
return this->getGeomSrc().fVertexSize;
}
// Subclass must initialize this in its constructor.
SkAutoTUnref<const GrDrawTargetCaps> fCaps;
const GrTraceMarkerSet& getActiveTraceMarkers() { return fActiveTraceMarkers; }
/**
* Used to communicate draws to subclass's onDraw function.
*/
class DrawInfo {
public:
DrawInfo(const DrawInfo& di) { (*this) = di; }
DrawInfo& operator =(const DrawInfo& di);
GrPrimitiveType primitiveType() const { return fPrimitiveType; }
int startVertex() const { return fStartVertex; }
int startIndex() const { return fStartIndex; }
int vertexCount() const { return fVertexCount; }
int indexCount() const { return fIndexCount; }
int verticesPerInstance() const { return fVerticesPerInstance; }
int indicesPerInstance() const { return fIndicesPerInstance; }
int instanceCount() const { return fInstanceCount; }
bool isIndexed() const { return fIndexCount > 0; }
#ifdef SK_DEBUG
bool isInstanced() const; // this version is longer because of asserts
#else
bool isInstanced() const { return fInstanceCount > 0; }
#endif
// adds or remove instances
void adjustInstanceCount(int instanceOffset);
// shifts the start vertex
void adjustStartVertex(int vertexOffset);
// shifts the start index
void adjustStartIndex(int indexOffset);
void setDevBounds(const SkRect& bounds) {
fDevBoundsStorage = bounds;
fDevBounds = &fDevBoundsStorage;
}
const SkRect* getDevBounds() const { return fDevBounds; }
// NULL if no copy of the dst is needed for the draw.
const GrDeviceCoordTexture* getDstCopy() const {
if (NULL != fDstCopy.texture()) {
return &fDstCopy;
} else {
return NULL;
}
}
private:
DrawInfo() { fDevBounds = NULL; }
friend class GrDrawTarget;
GrPrimitiveType fPrimitiveType;
int fStartVertex;
int fStartIndex;
int fVertexCount;
int fIndexCount;
int fInstanceCount;
int fVerticesPerInstance;
int fIndicesPerInstance;
SkRect fDevBoundsStorage;
SkRect* fDevBounds;
GrDeviceCoordTexture fDstCopy;
};
private:
// A subclass can optionally overload this function to be notified before
// vertex and index space is reserved.
virtual void willReserveVertexAndIndexSpace(int vertexCount, int indexCount) {}
// implemented by subclass to allocate space for reserved geom
virtual bool onReserveVertexSpace(size_t vertexSize, int vertexCount, void** vertices) = 0;
virtual bool onReserveIndexSpace(int indexCount, void** indices) = 0;
// implemented by subclass to handle release of reserved geom space
virtual void releaseReservedVertexSpace() = 0;
virtual void releaseReservedIndexSpace() = 0;
// subclass must consume array contents when set
virtual void onSetVertexSourceToArray(const void* vertexArray, int vertexCount) = 0;
virtual void onSetIndexSourceToArray(const void* indexArray, int indexCount) = 0;
// subclass is notified that geom source will be set away from an array
virtual void releaseVertexArray() = 0;
virtual void releaseIndexArray() = 0;
// subclass overrides to be notified just before geo src state is pushed/popped.
virtual void geometrySourceWillPush() = 0;
virtual void geometrySourceWillPop(const GeometrySrcState& restoredState) = 0;
// subclass called to perform drawing
virtual void onDraw(const DrawInfo&) = 0;
// Implementation of drawRect. The geometry src and vertex attribs will already
// be saved before this is called and restored afterwards. A subclass may override
// this to perform more optimal rect rendering. Its draws should be funneled through
// one of the public GrDrawTarget draw methods (e.g. drawNonIndexed,
// drawIndexedInstances, ...). The base class draws a two triangle fan using
// drawNonIndexed from reserved vertex space.
virtual void onDrawRect(const SkRect& rect,
const SkMatrix* matrix,
const SkRect* localRect,
const SkMatrix* localMatrix);
virtual void onStencilPath(const GrPath*, SkPath::FillType) = 0;
virtual void onDrawPath(const GrPath*, SkPath::FillType,
const GrDeviceCoordTexture* dstCopy) = 0;
virtual void onDrawPaths(int, const GrPath**, const SkMatrix*,
SkPath::FillType, SkStrokeRec::Style,
const GrDeviceCoordTexture* dstCopy) = 0;
virtual void didAddGpuTraceMarker() = 0;
virtual void didRemoveGpuTraceMarker() = 0;
// helpers for reserving vertex and index space.
bool reserveVertexSpace(size_t vertexSize,
int vertexCount,
void** vertices);
bool reserveIndexSpace(int indexCount, void** indices);
// called by drawIndexed and drawNonIndexed. Use a negative indexCount to
// indicate non-indexed drawing.
bool checkDraw(GrPrimitiveType type, int startVertex,
int startIndex, int vertexCount,
int indexCount) const;
// called when setting a new vert/idx source to unref prev vb/ib
void releasePreviousVertexSource();
void releasePreviousIndexSource();
// Makes a copy of the dst if it is necessary for the draw. Returns false if a copy is required
// but couldn't be made. Otherwise, returns true.
bool setupDstReadIfNecessary(DrawInfo* info) {
return this->setupDstReadIfNecessary(&info->fDstCopy, info->getDevBounds());
}
bool setupDstReadIfNecessary(GrDeviceCoordTexture* dstCopy, const SkRect* drawBounds);
// Check to see if this set of draw commands has been sent out
virtual bool isIssued(uint32_t drawID) { return true; }
enum {
kPreallocGeoSrcStateStackCnt = 4,
};
SkSTArray<kPreallocGeoSrcStateStackCnt, GeometrySrcState, true> fGeoSrcStateStack;
const GrClipData* fClip;
GrDrawState* fDrawState;
GrDrawState fDefaultDrawState;
// The context owns us, not vice-versa, so this ptr is not ref'ed by DrawTarget.
GrContext* fContext;
// To keep track that we always have at least as many debug marker adds as removes
int fGpuTraceMarkerCount;
GrTraceMarkerSet fActiveTraceMarkers;
GrTraceMarkerSet fStoredTraceMarkers;
typedef SkRefCnt INHERITED;
};
#endif