| |
| /* |
| * 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 "GrDrawState.h" |
| #include "GrIndexBuffer.h" |
| #include "GrMatrix.h" |
| #include "GrRefCnt.h" |
| #include "GrTemplates.h" |
| |
| #include "SkXfermode.h" |
| #include "SkTLazy.h" |
| #include "SkTArray.h" |
| |
| class GrClipData; |
| class GrPath; |
| class GrVertexBuffer; |
| |
| class GrDrawTarget : public GrRefCnt { |
| public: |
| SK_DECLARE_INST_COUNT(GrDrawTarget) |
| |
| /** |
| * Represents the draw target capabilities. |
| */ |
| struct Caps { |
| Caps() { memset(this, 0, sizeof(Caps)); } |
| Caps(const Caps& c) { *this = c; } |
| Caps& operator= (const Caps& c) { |
| memcpy(this, &c, sizeof(Caps)); |
| return *this; |
| } |
| void print() const; |
| bool f8BitPaletteSupport : 1; |
| bool fNPOTTextureTileSupport : 1; |
| bool fTwoSidedStencilSupport : 1; |
| bool fStencilWrapOpsSupport : 1; |
| bool fHWAALineSupport : 1; |
| bool fShaderDerivativeSupport : 1; |
| bool fGeometryShaderSupport : 1; |
| bool fFSAASupport : 1; |
| bool fDualSourceBlendingSupport : 1; |
| bool fBufferLockSupport : 1; |
| bool fPathStencilingSupport : 1; |
| int fMaxRenderTargetSize; |
| int fMaxTextureSize; |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////// |
| |
| GrDrawTarget(); |
| virtual ~GrDrawTarget(); |
| |
| /** |
| * Gets the capabilities of the draw target. |
| */ |
| const Caps& getCaps() const { return fCaps; } |
| |
| /** |
| * 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, the current configuration of |
| * the target's GrDrawState is as it will be at draw time. |
| * 3. If a vertex source has not yet been specified then all stages with |
| * non-NULL textures will be referenced by the vertex layout. |
| */ |
| bool canApplyCoverage() const; |
| |
| /** |
| * Determines whether incorporating partial pixel coverage into the constant |
| * color specified by setColor or per-vertex colors will give the right |
| * blending result. If a vertex source has not yet been specified then |
| * the function assumes that all stages with non-NULL textures will be |
| * referenced by the vertex layout. |
| */ |
| bool canTweakAlphaForCoverage() const; |
| |
| /** |
| * Given the current draw state and hw support, will HW AA lines be used |
| * (if line primitive type is drawn)? If a vertex source has not yet been |
| * specified then the function assumes that all stages with non-NULL |
| * textures will be referenced by the vertex layout. |
| */ |
| bool willUseHWAALines() const; |
| |
| /** |
| * The format of vertices is represented as a bitfield of flags. |
| * Flags that indicate the layout of vertex data. Vertices always contain |
| * positions and may also contain up to GrDrawState::kMaxTexCoords sets |
| * of 2D texture coordinates, per-vertex colors, and per-vertex coverage. |
| * Each stage can |
| * use any of the texture coordinates as its input texture coordinates or it |
| * may use the positions as texture coordinates. |
| * |
| * If no texture coordinates are specified for a stage then the stage is |
| * disabled. |
| * |
| * Only one type of texture coord can be specified per stage. For |
| * example StageTexCoordVertexLayoutBit(0, 2) and |
| * StagePosAsTexCoordVertexLayoutBit(0) cannot both be specified. |
| * |
| * The order in memory is always (position, texture coord 0, ..., color, |
| * coverage) with any unused fields omitted. Note that this means that if |
| * only texture coordinates 1 is referenced then there is no texture |
| * coordinates 0 and the order would be (position, texture coordinate 1 |
| * [, color][, coverage]). |
| */ |
| |
| /** |
| * Generates a bit indicating that a texture stage uses texture coordinates |
| * |
| * @param stage the stage that will use texture coordinates. |
| * @param texCoordIdx the index of the texture coordinates to use |
| * |
| * @return the bit to add to a GrVertexLayout bitfield. |
| */ |
| static int StageTexCoordVertexLayoutBit(int stage, int texCoordIdx) { |
| GrAssert(stage < GrDrawState::kNumStages); |
| GrAssert(texCoordIdx < GrDrawState::kMaxTexCoords); |
| return 1 << (stage + (texCoordIdx * GrDrawState::kNumStages)); |
| } |
| |
| static bool StageUsesTexCoords(GrVertexLayout layout, int stage); |
| |
| private: |
| // non-stage bits start at this index. |
| static const int STAGE_BIT_CNT = GrDrawState::kNumStages * |
| GrDrawState::kMaxTexCoords; |
| public: |
| |
| /** |
| * Additional Bits that can be specified in GrVertexLayout. |
| */ |
| enum VertexLayoutBits { |
| /* vertices have colors (GrColor) */ |
| kColor_VertexLayoutBit = 1 << (STAGE_BIT_CNT + 0), |
| /* vertices have coverage (GrColor) |
| */ |
| kCoverage_VertexLayoutBit = 1 << (STAGE_BIT_CNT + 1), |
| /* Use text vertices. (Pos and tex coords may be a different type for |
| * text [GrGpuTextVertex vs GrPoint].) |
| */ |
| kTextFormat_VertexLayoutBit = 1 << (STAGE_BIT_CNT + 2), |
| |
| /* Each vertex specificies an edge. Distance to the edge is used to |
| * compute a coverage. See GrDrawState::setVertexEdgeType(). |
| */ |
| kEdge_VertexLayoutBit = 1 << (STAGE_BIT_CNT + 3), |
| // for below assert |
| kDummyVertexLayoutBit, |
| kHighVertexLayoutBit = kDummyVertexLayoutBit - 1 |
| }; |
| // make sure we haven't exceeded the number of bits in GrVertexLayout. |
| GR_STATIC_ASSERT(kHighVertexLayoutBit < ((uint64_t)1 << 8*sizeof(GrVertexLayout))); |
| |
| /** |
| * 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, 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) |
| */ |
| |
| /** |
| * 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, or push/ |
| * popGeomtrySource is called. At that point logically a snapshot of the |
| * data is made and the pointers are invalid. |
| * |
| * @param vertexLayout the format of vertices (ignored if vertexCount == 0). |
| * @param vertexCount the number of vertices to reserve space for. Can be |
| * 0. |
| * @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(GrVertexLayout vertexLayout, |
| 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 vertexLayout layout of vertices caller would like to reserve |
| * @param vertexCount in: hint about how many vertices the caller would |
| * like to allocate. |
| * 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(GrVertexLayout vertexLayout, |
| 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 array cpu array containing vertex data. |
| * @param size size of the vertex data. |
| * @param vertexCount the number of vertices in the array. |
| */ |
| void setVertexSourceToArray(GrVertexLayout vertexLayout, |
| 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 array 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. |
| * @param vertexLayout layout of the vertex data in the buffer. |
| */ |
| void setVertexSourceToBuffer(GrVertexLayout vertexLayout, |
| 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. |
| */ |
| void drawIndexed(GrPrimitiveType type, |
| int startVertex, |
| int startIndex, |
| int vertexCount, |
| int indexCount); |
| |
| /** |
| * 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. |
| */ |
| void drawNonIndexed(GrPrimitiveType type, |
| int startVertex, |
| int vertexCount); |
| |
| /** |
| * 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*, GrPathFill); |
| |
| /** |
| * Helper function for drawing rects. This does not use the current index |
| * and vertex sources. After returning, the vertex and index sources may |
| * have changed. They should be reestablished before the next drawIndexed |
| * or drawNonIndexed. This cannot be called between reserving and releasing |
| * geometry. The GrDrawTarget subclass may be able to perform additional |
| * optimizations if drawRect is used rather than drawIndexed or |
| * drawNonIndexed. |
| * @param rect the rect to draw |
| * @param matrix optional matrix applied to rect (before viewMatrix) |
| * @param srcRects specifies rects for stages enabled by stageEnableMask. |
| * if stageEnableMask bit i is 1, srcRects is not NULL, |
| * and srcRects[i] is not NULL, then srcRects[i] will be |
| * used as coordinates for stage i. Otherwise, if stage i |
| * is enabled then rect is used as the coordinates. |
| * @param srcMatrices optional matrices applied to srcRects. If |
| * srcRect[i] is non-NULL and srcMatrices[i] is |
| * non-NULL then srcRect[i] will be transformed by |
| * srcMatrix[i]. srcMatrices can be NULL when no |
| * srcMatrices are desired. |
| */ |
| virtual void drawRect(const GrRect& rect, |
| const GrMatrix* matrix, |
| const GrRect* srcRects[], |
| const GrMatrix* srcMatrices[]); |
| |
| /** |
| * 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. Morever, 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). |
| */ |
| virtual void drawIndexedInstances(GrPrimitiveType type, |
| int instanceCount, |
| int verticesPerInstance, |
| int indicesPerInstance); |
| |
| /** |
| * Helper for drawRect when the caller doesn't need separate src rects or |
| * matrices. |
| */ |
| void drawSimpleRect(const GrRect& rect, |
| const GrMatrix* matrix) { |
| drawRect(rect, matrix, NULL, 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. |
| */ |
| virtual void clear(const GrIRect* rect, |
| GrColor color, |
| GrRenderTarget* renderTarget = NULL) = 0; |
| |
| /** |
| * 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() {}; |
| |
| //////////////////////////////////////////////////////////////////////////// |
| |
| /** |
| * 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 : ::GrNoncopyable { |
| 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. |
| */ |
| AutoStateRestore(GrDrawTarget* target, ASRInit init); |
| |
| ~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. |
| */ |
| void set(GrDrawTarget* target, ASRInit init); |
| |
| private: |
| GrDrawTarget* fDrawTarget; |
| SkTLazy<GrDrawState> fTempState; |
| GrDrawState* fSavedState; |
| }; |
| |
| //////////////////////////////////////////////////////////////////////////// |
| |
| /** |
| * Sets the view matrix to I and preconcats all stage matrices enabled in |
| * mask by the view inverse. Destructor undoes these changes. |
| */ |
| class AutoDeviceCoordDraw : ::GrNoncopyable { |
| public: |
| /** |
| * If a stage's texture matrix is applied to explicit per-vertex coords, |
| * rather than to positions, then we don't want to modify its matrix. |
| * The explicitCoordStageMask is used to specify such stages. |
| * |
| * TODO: Remove this when custom stage's control their own texture |
| * matrix and there is a "view matrix has changed" notification to the |
| * custom stages. |
| */ |
| AutoDeviceCoordDraw(GrDrawTarget* target, |
| uint32_t explicitCoordStageMask = 0); |
| bool succeeded() const { return NULL != fDrawTarget; } |
| ~AutoDeviceCoordDraw(); |
| private: |
| GrDrawTarget* fDrawTarget; |
| GrMatrix fViewMatrix; |
| GrMatrix fSamplerMatrices[GrDrawState::kNumStages]; |
| int fRestoreMask; |
| }; |
| |
| //////////////////////////////////////////////////////////////////////////// |
| |
| class AutoReleaseGeometry : ::GrNoncopyable { |
| public: |
| AutoReleaseGeometry(GrDrawTarget* target, |
| GrVertexLayout vertexLayout, |
| int vertexCount, |
| int indexCount); |
| AutoReleaseGeometry(); |
| ~AutoReleaseGeometry(); |
| bool set(GrDrawTarget* target, |
| GrVertexLayout vertexLayout, |
| int vertexCount, |
| int indexCount); |
| bool succeeded() const { return NULL != fTarget; } |
| void* vertices() const { GrAssert(this->succeeded()); return fVertices; } |
| void* indices() const { GrAssert(this->succeeded()); return fIndices; } |
| GrPoint* positions() const { |
| return static_cast<GrPoint*>(this->vertices()); |
| } |
| |
| private: |
| void reset(); |
| |
| GrDrawTarget* fTarget; |
| void* fVertices; |
| void* fIndices; |
| }; |
| |
| //////////////////////////////////////////////////////////////////////////// |
| |
| class AutoClipRestore : ::GrNoncopyable { |
| public: |
| AutoClipRestore(GrDrawTarget* target) { |
| fTarget = target; |
| fClip = fTarget->getClip(); |
| } |
| |
| ~AutoClipRestore() { |
| fTarget->setClip(fClip); |
| } |
| private: |
| GrDrawTarget* fTarget; |
| const GrClipData* fClip; |
| }; |
| |
| //////////////////////////////////////////////////////////////////////////// |
| |
| class AutoGeometryPush : ::GrNoncopyable { |
| public: |
| AutoGeometryPush(GrDrawTarget* target) { |
| GrAssert(NULL != target); |
| fTarget = target; |
| target->pushGeometrySource(); |
| } |
| ~AutoGeometryPush() { |
| fTarget->popGeometrySource(); |
| } |
| private: |
| GrDrawTarget* fTarget; |
| }; |
| |
| //////////////////////////////////////////////////////////////////////////// |
| // Helpers for picking apart vertex layouts |
| |
| /** |
| * Helper function to compute the size of a vertex from a vertex layout |
| * @return size of a single vertex. |
| */ |
| static size_t VertexSize(GrVertexLayout vertexLayout); |
| |
| /** |
| * Helper function for determining the index of texture coordinates that |
| * is input for a texture stage. Note that a stage may instead use positions |
| * as texture coordinates, in which case the result of the function is |
| * indistinguishable from the case when the stage is disabled. |
| * |
| * @param stage the stage to query |
| * @param vertexLayout layout to query |
| * |
| * @return the texture coordinate index or -1 if the stage doesn't use |
| * separate (non-position) texture coordinates. |
| */ |
| static int VertexTexCoordsForStage(int stage, GrVertexLayout vertexLayout); |
| |
| /** |
| * Helper function to compute the offset of texture coordinates in a vertex |
| * @return offset of texture coordinates in vertex layout or -1 if the |
| * layout has no texture coordinates. Will be 0 if positions are |
| * used as texture coordinates for the stage. |
| */ |
| static int VertexStageCoordOffset(int stage, GrVertexLayout vertexLayout); |
| |
| /** |
| * Helper function to compute the offset of the color in a vertex |
| * @return offset of color in vertex layout or -1 if the |
| * layout has no color. |
| */ |
| static int VertexColorOffset(GrVertexLayout vertexLayout); |
| |
| /** |
| * Helper function to compute the offset of the coverage in a vertex |
| * @return offset of coverage in vertex layout or -1 if the |
| * layout has no coverage. |
| */ |
| static int VertexCoverageOffset(GrVertexLayout vertexLayout); |
| |
| /** |
| * Helper function to compute the offset of the edge pts in a vertex |
| * @return offset of edge in vertex layout or -1 if the |
| * layout has no edge. |
| */ |
| static int VertexEdgeOffset(GrVertexLayout vertexLayout); |
| |
| /** |
| * Helper function to determine if vertex layout contains explicit texture |
| * coordinates of some index. |
| * |
| * @param coordIndex the tex coord index to query |
| * @param vertexLayout layout to query |
| * |
| * @return true if vertex specifies texture coordinates for the index, |
| * false otherwise. |
| */ |
| static bool VertexUsesTexCoordIdx(int coordIndex, |
| GrVertexLayout vertexLayout); |
| |
| /** |
| * Helper function to compute the size of each vertex and the offsets of |
| * texture coordinates and color. Determines tex coord offsets by tex coord |
| * index rather than by stage. (Each stage can be mapped to any t.c. index |
| * by StageTexCoordVertexLayoutBit.) |
| * |
| * @param vertexLayout the layout to query |
| * @param texCoordOffsetsByIdx after return it is the offset of each |
| * tex coord index in the vertex or -1 if |
| * index isn't used. (optional) |
| * @param colorOffset after return it is the offset of the |
| * color field in each vertex, or -1 if |
| * there aren't per-vertex colors. (optional) |
| * @param coverageOffset after return it is the offset of the |
| * coverage field in each vertex, or -1 if |
| * there aren't per-vertex coeverages. |
| * (optional) |
| * @param edgeOffset after return it is the offset of the |
| * edge eq field in each vertex, or -1 if |
| * there aren't per-vertex edge equations. |
| * (optional) |
| * @return size of a single vertex |
| */ |
| static int VertexSizeAndOffsetsByIdx(GrVertexLayout vertexLayout, |
| int texCoordOffsetsByIdx[GrDrawState::kMaxTexCoords], |
| int *colorOffset, |
| int *coverageOffset, |
| int* edgeOffset); |
| |
| /** |
| * Helper function to compute the size of each vertex and the offsets of |
| * texture coordinates and color. Determines tex coord offsets by stage |
| * rather than by index. (Each stage can be mapped to any t.c. index |
| * by StageTexCoordVertexLayoutBit.) If a stage uses positions for |
| * tex coords then that stage's offset will be 0 (positions are always at 0). |
| * |
| * @param vertexLayout the layout to query |
| * @param texCoordOffsetsByStage after return it is the offset of each |
| * tex coord index in the vertex or -1 if |
| * index isn't used. (optional) |
| * @param colorOffset after return it is the offset of the |
| * color field in each vertex, or -1 if |
| * there aren't per-vertex colors. |
| * (optional) |
| * @param coverageOffset after return it is the offset of the |
| * coverage field in each vertex, or -1 if |
| * there aren't per-vertex coeverages. |
| * (optional) |
| * @param edgeOffset after return it is the offset of the |
| * edge eq field in each vertex, or -1 if |
| * there aren't per-vertex edge equations. |
| * (optional) |
| * @return size of a single vertex |
| */ |
| static int VertexSizeAndOffsetsByStage(GrVertexLayout vertexLayout, |
| int texCoordOffsetsByStage[GrDrawState::kNumStages], |
| int* colorOffset, |
| int* coverageOffset, |
| int* edgeOffset); |
| |
| /** |
| * Accessing positions, texture coords, or colors, of a vertex within an |
| * array is a hassle involving casts and simple math. These helpers exist |
| * to keep GrDrawTarget clients' code a bit nicer looking. |
| */ |
| |
| /** |
| * Gets a pointer to a GrPoint of a vertex's position or texture |
| * coordinate. |
| * @param vertices the vetex array |
| * @param vertexIndex the index of the vertex in the array |
| * @param vertexSize the size of each vertex in the array |
| * @param offset the offset in bytes of the vertex component. |
| * Defaults to zero (corresponding to vertex position) |
| * @return pointer to the vertex component as a GrPoint |
| */ |
| static GrPoint* GetVertexPoint(void* vertices, |
| int vertexIndex, |
| int vertexSize, |
| int offset = 0) { |
| intptr_t start = GrTCast<intptr_t>(vertices); |
| return GrTCast<GrPoint*>(start + offset + |
| vertexIndex * vertexSize); |
| } |
| static const GrPoint* GetVertexPoint(const void* vertices, |
| int vertexIndex, |
| int vertexSize, |
| int offset = 0) { |
| intptr_t start = GrTCast<intptr_t>(vertices); |
| return GrTCast<const GrPoint*>(start + offset + |
| vertexIndex * vertexSize); |
| } |
| |
| /** |
| * Gets a pointer to a GrColor inside a vertex within a vertex array. |
| * @param vertices the vetex array |
| * @param vertexIndex the index of the vertex in the array |
| * @param vertexSize the size of each vertex in the array |
| * @param offset the offset in bytes of the vertex color |
| * @return pointer to the vertex component as a GrColor |
| */ |
| static GrColor* GetVertexColor(void* vertices, |
| int vertexIndex, |
| int vertexSize, |
| int offset) { |
| intptr_t start = GrTCast<intptr_t>(vertices); |
| return GrTCast<GrColor*>(start + offset + |
| vertexIndex * vertexSize); |
| } |
| static const GrColor* GetVertexColor(const void* vertices, |
| int vertexIndex, |
| int vertexSize, |
| int offset) { |
| const intptr_t start = GrTCast<intptr_t>(vertices); |
| return GrTCast<const GrColor*>(start + offset + |
| vertexIndex * vertexSize); |
| } |
| |
| static void VertexLayoutUnitTest(); |
| |
| protected: |
| |
| /** |
| * Optimizations for blending / coverage to be applied based on the current |
| * state. |
| * Subclasses that actually draw (as opposed to those that just buffer for |
| * playback) must implement the flags that replace the output color. |
| */ |
| enum BlendOptFlags { |
| /** |
| * No optimization |
| */ |
| kNone_BlendOpt = 0, |
| /** |
| * Don't draw at all |
| */ |
| kSkipDraw_BlendOptFlag = 0x2, |
| /** |
| * Emit the src color, disable HW blending (replace dst with src) |
| */ |
| kDisableBlend_BlendOptFlag = 0x4, |
| /** |
| * The coverage value does not have to be computed separately from |
| * alpha, the the output color can be the modulation of the two. |
| */ |
| kCoverageAsAlpha_BlendOptFlag = 0x1, |
| /** |
| * Instead of emitting a src color, emit coverage in the alpha channel |
| * and r,g,b are "don't cares". |
| */ |
| kEmitCoverage_BlendOptFlag = 0x10, |
| /** |
| * Emit transparent black instead of the src color, no need to compute |
| * coverage. |
| */ |
| kEmitTransBlack_BlendOptFlag = 0x8, |
| }; |
| GR_DECL_BITFIELD_OPS_FRIENDS(BlendOptFlags); |
| |
| // Determines what optimizations can be applied based on the blend. |
| // The coeffecients may have to be tweaked in order for the optimization |
| // to work. srcCoeff and dstCoeff are optional params that receive the |
| // tweaked coeffecients. |
| // Normally the function looks at the current state to see if coverage |
| // is enabled. By setting forceCoverage the caller can speculatively |
| // determine the blend optimizations that would be used if there was |
| // partial pixel coverage |
| BlendOptFlags getBlendOpts(bool forceCoverage = false, |
| GrBlendCoeff* srcCoeff = NULL, |
| GrBlendCoeff* dstCoeff = NULL) const; |
| |
| // determine if src alpha is guaranteed to be one for all src pixels |
| bool srcAlphaWillBeOne(GrVertexLayout vertexLayout) const; |
| |
| 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; |
| }; |
| |
| GrVertexLayout fVertexLayout; |
| }; |
| |
| 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 src.fIndexBuffer->sizeInBytes() / sizeof(uint16_t); |
| default: |
| GrCrash("Unexpected Index Source."); |
| return 0; |
| } |
| } |
| |
| bool isStageEnabled(int stage) const { |
| return this->getDrawState().isStageEnabled(stage); |
| } |
| |
| // A sublcass can optionally overload this function to be notified before |
| // vertex and index space is reserved. |
| virtual void willReserveVertexAndIndexSpace(GrVertexLayout vertexLayout, |
| int vertexCount, |
| int indexCount) {} |
| |
| |
| // implemented by subclass to allocate space for reserved geom |
| virtual bool onReserveVertexSpace(GrVertexLayout vertexLayout, |
| 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 onDrawIndexed(GrPrimitiveType type, |
| int startVertex, |
| int startIndex, |
| int vertexCount, |
| int indexCount) = 0; |
| virtual void onDrawNonIndexed(GrPrimitiveType type, |
| int startVertex, |
| int vertexCount) = 0; |
| virtual void onStencilPath(const GrPath*, GrPathFill) = 0; |
| |
| // subclass overrides to be notified when clip is set. Must call |
| // INHERITED::clipwillBeSet |
| virtual void clipWillBeSet(const GrClipData* clipData) {} |
| |
| // Helpers for drawRect, protected so subclasses that override drawRect |
| // can use them. |
| static GrVertexLayout GetRectVertexLayout(const GrRect* srcRects[]); |
| |
| static void SetRectVertices(const GrRect& rect, |
| const GrMatrix* matrix, |
| const GrRect* srcRects[], |
| const GrMatrix* srcMatrices[], |
| GrVertexLayout layout, |
| void* vertices); |
| |
| // accessors for derived classes |
| const GeometrySrcState& getGeomSrc() const { |
| return fGeoSrcStateStack.back(); |
| } |
| // it is prefereable to call this rather than getGeomSrc()->fVertexLayout |
| // because of the assert. |
| GrVertexLayout getVertexLayout() const { |
| // the vertex layout is only valid if a vertex source has been |
| // specified. |
| GrAssert(this->getGeomSrc().fVertexSrc != kNone_GeometrySrcType); |
| return this->getGeomSrc().fVertexLayout; |
| } |
| |
| const GrClipData* fClip; |
| |
| GrDrawState* fDrawState; |
| GrDrawState fDefaultDrawState; |
| |
| Caps fCaps; |
| |
| // subclasses must call this in their destructors to ensure all vertex |
| // and index sources have been released (including those held by |
| // pushGeometrySource()) |
| void releaseGeometry(); |
| |
| private: |
| // helpers for reserving vertex and index space. |
| bool reserveVertexSpace(GrVertexLayout vertexLayout, |
| 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(); |
| |
| enum { |
| kPreallocGeoSrcStateStackCnt = 4, |
| }; |
| SkSTArray<kPreallocGeoSrcStateStackCnt, |
| GeometrySrcState, true> fGeoSrcStateStack; |
| |
| typedef GrRefCnt INHERITED; |
| }; |
| |
| GR_MAKE_BITFIELD_OPS(GrDrawTarget::BlendOptFlags); |
| |
| #endif |