gfx/skia/trunk/src/gpu/GrGpu.h@6474c204b198
gfx/skia/trunk/src/gpu/GrGpu.h
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
1 /*
2 * Copyright 2011 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
8 #ifndef GrGpu_DEFINED
9 #define GrGpu_DEFINED
11 #include "GrDrawTarget.h"
12 #include "GrClipMaskManager.h"
13 #include "SkPath.h"
15 class GrContext;
16 class GrIndexBufferAllocPool;
17 class GrPath;
18 class GrPathRenderer;
19 class GrPathRendererChain;
20 class GrResource;
21 class GrStencilBuffer;
22 class GrVertexBufferAllocPool;
24 class GrGpu : public GrDrawTarget {
25 public:
27 /**
28 * Additional blend coefficients for dual source blending, not exposed
29 * through GrPaint/GrContext.
30 */
31 enum ExtendedBlendCoeffs {
32 // source 2 refers to second output color when
33 // using dual source blending.
34 kS2C_GrBlendCoeff = kPublicGrBlendCoeffCount,
35 kIS2C_GrBlendCoeff,
36 kS2A_GrBlendCoeff,
37 kIS2A_GrBlendCoeff,
39 kTotalGrBlendCoeffCount
40 };
42 /**
43 * Create an instance of GrGpu that matches the specified backend. If the requested backend is
44 * not supported (at compile-time or run-time) this returns NULL. The context will not be
45 * fully constructed and should not be used by GrGpu until after this function returns.
46 */
47 static GrGpu* Create(GrBackend, GrBackendContext, GrContext* context);
49 ////////////////////////////////////////////////////////////////////////////
51 GrGpu(GrContext* context);
52 virtual ~GrGpu();
54 GrContext* getContext() { return this->INHERITED::getContext(); }
55 const GrContext* getContext() const { return this->INHERITED::getContext(); }
57 /**
58 * The GrGpu object normally assumes that no outsider is setting state
59 * within the underlying 3D API's context/device/whatever. This call informs
60 * the GrGpu that the state was modified and it shouldn't make assumptions
61 * about the state.
62 */
63 void markContextDirty(uint32_t state = kAll_GrBackendState) {
64 fResetBits |= state;
65 }
67 void unimpl(const char[]);
69 /**
70 * Creates a texture object. If desc width or height is not a power of
71 * two but underlying API requires a power of two texture then srcData
72 * will be embedded in a power of two texture. The extra width and height
73 * is filled as though srcData were rendered clamped into the texture.
74 *
75 * If kRenderTarget_TextureFlag is specified the GrRenderTarget is
76 * accessible via GrTexture::asRenderTarget(). The texture will hold a ref
77 * on the render target until the texture is destroyed.
78 *
79 * @param desc describes the texture to be created.
80 * @param srcData texel data to load texture. Begins with full-size
81 * palette data for paletted textures. Contains width*
82 * height texels. If NULL texture data is uninitialized.
83 *
84 * @return The texture object if successful, otherwise NULL.
85 */
86 GrTexture* createTexture(const GrTextureDesc& desc,
87 const void* srcData, size_t rowBytes);
89 /**
90 * Implements GrContext::wrapBackendTexture
91 */
92 GrTexture* wrapBackendTexture(const GrBackendTextureDesc&);
94 /**
95 * Implements GrContext::wrapBackendTexture
96 */
97 GrRenderTarget* wrapBackendRenderTarget(const GrBackendRenderTargetDesc&);
99 /**
100 * Creates a vertex buffer.
101 *
102 * @param size size in bytes of the vertex buffer
103 * @param dynamic hints whether the data will be frequently changed
104 * by either GrVertexBuffer::lock or
105 * GrVertexBuffer::updateData.
106 *
107 * @return The vertex buffer if successful, otherwise NULL.
108 */
109 GrVertexBuffer* createVertexBuffer(size_t size, bool dynamic);
111 /**
112 * Creates an index buffer.
113 *
114 * @param size size in bytes of the index buffer
115 * @param dynamic hints whether the data will be frequently changed
116 * by either GrIndexBuffer::lock or
117 * GrIndexBuffer::updateData.
118 *
119 * @return The index buffer if successful, otherwise NULL.
120 */
121 GrIndexBuffer* createIndexBuffer(size_t size, bool dynamic);
123 /**
124 * Creates a path object that can be stenciled using stencilPath(). It is
125 * only legal to call this if the caps report support for path stenciling.
126 */
127 GrPath* createPath(const SkPath& path, const SkStrokeRec& stroke);
129 /**
130 * Returns an index buffer that can be used to render quads.
131 * Six indices per quad: 0, 1, 2, 0, 2, 3, etc.
132 * The max number of quads can be queried using GrIndexBuffer::maxQuads().
133 * Draw with kTriangles_GrPrimitiveType
134 * @ return the quad index buffer
135 */
136 const GrIndexBuffer* getQuadIndexBuffer() const;
138 /**
139 * Resolves MSAA.
140 */
141 void resolveRenderTarget(GrRenderTarget* target);
143 /**
144 * Ensures that the current render target is actually set in the
145 * underlying 3D API. Used when client wants to use 3D API to directly
146 * render to the RT.
147 */
148 void forceRenderTargetFlush();
150 /**
151 * Gets a preferred 8888 config to use for writing/reading pixel data to/from a surface with
152 * config surfaceConfig. The returned config must have at least as many bits per channel as the
153 * readConfig or writeConfig param.
154 */
155 virtual GrPixelConfig preferredReadPixelsConfig(GrPixelConfig readConfig,
156 GrPixelConfig surfaceConfig) const {
157 return readConfig;
158 }
159 virtual GrPixelConfig preferredWritePixelsConfig(GrPixelConfig writeConfig,
160 GrPixelConfig surfaceConfig) const {
161 return writeConfig;
162 }
164 /**
165 * Called before uploading writing pixels to a GrTexture when the src pixel config doesn't
166 * match the texture's config.
167 */
168 virtual bool canWriteTexturePixels(const GrTexture*, GrPixelConfig srcConfig) const = 0;
170 /**
171 * OpenGL's readPixels returns the result bottom-to-top while the skia
172 * API is top-to-bottom. Thus we have to do a y-axis flip. The obvious
173 * solution is to have the subclass do the flip using either the CPU or GPU.
174 * However, the caller (GrContext) may have transformations to apply and can
175 * simply fold in the y-flip for free. On the other hand, the subclass may
176 * be able to do it for free itself. For example, the subclass may have to
177 * do memcpys to handle rowBytes that aren't tight. It could do the y-flip
178 * concurrently.
179 *
180 * This function returns true if a y-flip is required to put the pixels in
181 * top-to-bottom order and the subclass cannot do it for free.
182 *
183 * See read pixels for the params
184 * @return true if calling readPixels with the same set of params will
185 * produce bottom-to-top data
186 */
187 virtual bool readPixelsWillPayForYFlip(GrRenderTarget* renderTarget,
188 int left, int top,
189 int width, int height,
190 GrPixelConfig config,
191 size_t rowBytes) const = 0;
192 /**
193 * This should return true if reading a NxM rectangle of pixels from a
194 * render target is faster if the target has dimensons N and M and the read
195 * rectangle has its top-left at 0,0.
196 */
197 virtual bool fullReadPixelsIsFasterThanPartial() const { return false; };
199 /**
200 * Reads a rectangle of pixels from a render target.
201 *
202 * @param renderTarget the render target to read from. NULL means the
203 * current render target.
204 * @param left left edge of the rectangle to read (inclusive)
205 * @param top top edge of the rectangle to read (inclusive)
206 * @param width width of rectangle to read in pixels.
207 * @param height height of rectangle to read in pixels.
208 * @param config the pixel config of the destination buffer
209 * @param buffer memory to read the rectangle into.
210 * @param rowBytes the number of bytes between consecutive rows. Zero
211 * means rows are tightly packed.
212 * @param invertY buffer should be populated bottom-to-top as opposed
213 * to top-to-bottom (skia's usual order)
214 *
215 * @return true if the read succeeded, false if not. The read can fail
216 * because of a unsupported pixel config or because no render
217 * target is currently set.
218 */
219 bool readPixels(GrRenderTarget* renderTarget,
220 int left, int top, int width, int height,
221 GrPixelConfig config, void* buffer, size_t rowBytes);
223 /**
224 * Updates the pixels in a rectangle of a texture.
225 *
226 * @param left left edge of the rectangle to write (inclusive)
227 * @param top top edge of the rectangle to write (inclusive)
228 * @param width width of rectangle to write in pixels.
229 * @param height height of rectangle to write in pixels.
230 * @param config the pixel config of the source buffer
231 * @param buffer memory to read pixels from
232 * @param rowBytes number of bytes between consecutive rows. Zero
233 * means rows are tightly packed.
234 */
235 bool writeTexturePixels(GrTexture* texture,
236 int left, int top, int width, int height,
237 GrPixelConfig config, const void* buffer,
238 size_t rowBytes);
240 /**
241 * Called to tell Gpu object that all GrResources have been lost and should
242 * be abandoned. Overrides must call INHERITED::abandonResources().
243 */
244 virtual void abandonResources();
246 /**
247 * Called to tell Gpu object to release all GrResources. Overrides must call
248 * INHERITED::releaseResources().
249 */
250 void releaseResources();
252 /**
253 * Add resource to list of resources. Should only be called by GrResource.
254 * @param resource the resource to add.
255 */
256 void insertResource(GrResource* resource);
258 /**
259 * Remove resource from list of resources. Should only be called by
260 * GrResource.
261 * @param resource the resource to remove.
262 */
263 void removeResource(GrResource* resource);
265 // GrDrawTarget overrides
266 virtual void clear(const SkIRect* rect,
267 GrColor color,
268 bool canIgnoreRect,
269 GrRenderTarget* renderTarget = NULL) SK_OVERRIDE;
271 virtual void purgeResources() SK_OVERRIDE {
272 // The clip mask manager can rebuild all its clip masks so just
273 // get rid of them all.
274 fClipMaskManager.releaseResources();
275 }
277 // After the client interacts directly with the 3D context state the GrGpu
278 // must resync its internal state and assumptions about 3D context state.
279 // Each time this occurs the GrGpu bumps a timestamp.
280 // state of the 3D context
281 // At 10 resets / frame and 60fps a 64bit timestamp will overflow in about
282 // a billion years.
283 typedef uint64_t ResetTimestamp;
285 // This timestamp is always older than the current timestamp
286 static const ResetTimestamp kExpiredTimestamp = 0;
287 // Returns a timestamp based on the number of times the context was reset.
288 // This timestamp can be used to lazily detect when cached 3D context state
289 // is dirty.
290 ResetTimestamp getResetTimestamp() const {
291 return fResetTimestamp;
292 }
294 /**
295 * These methods are called by the clip manager's setupClipping function
296 * which (called as part of GrGpu's implementation of onDraw and
297 * onStencilPath member functions.) The GrGpu subclass should flush the
298 * stencil state to the 3D API in its implementation of flushGraphicsState.
299 */
300 void enableScissor(const SkIRect& rect) {
301 fScissorState.fEnabled = true;
302 fScissorState.fRect = rect;
303 }
304 void disableScissor() { fScissorState.fEnabled = false; }
306 /**
307 * Like the scissor methods above this is called by setupClipping and
308 * should be flushed by the GrGpu subclass in flushGraphicsState. These
309 * stencil settings should be used in place of those on the GrDrawState.
310 * They have been adjusted to account for any interactions between the
311 * GrDrawState's stencil settings and stencil clipping.
312 */
313 void setStencilSettings(const GrStencilSettings& settings) {
314 fStencilSettings = settings;
315 }
316 void disableStencil() { fStencilSettings.setDisabled(); }
318 // GrGpu subclass sets clip bit in the stencil buffer. The subclass is
319 // free to clear the remaining bits to zero if masked clears are more
320 // expensive than clearing all bits.
321 virtual void clearStencilClip(const SkIRect& rect, bool insideClip) = 0;
323 enum PrivateDrawStateStateBits {
324 kFirstBit = (GrDrawState::kLastPublicStateBit << 1),
326 kModifyStencilClip_StateBit = kFirstBit, // allows draws to modify
327 // stencil bits used for
328 // clipping.
329 };
331 void getPathStencilSettingsForFillType(SkPath::FillType fill, GrStencilSettings* outStencilSettings);
333 protected:
334 enum DrawType {
335 kDrawPoints_DrawType,
336 kDrawLines_DrawType,
337 kDrawTriangles_DrawType,
338 kStencilPath_DrawType,
339 kDrawPath_DrawType,
340 };
342 DrawType PrimTypeToDrawType(GrPrimitiveType type) {
343 switch (type) {
344 case kTriangles_GrPrimitiveType:
345 case kTriangleStrip_GrPrimitiveType:
346 case kTriangleFan_GrPrimitiveType:
347 return kDrawTriangles_DrawType;
348 case kPoints_GrPrimitiveType:
349 return kDrawPoints_DrawType;
350 case kLines_GrPrimitiveType:
351 case kLineStrip_GrPrimitiveType:
352 return kDrawLines_DrawType;
353 default:
354 GrCrash("Unexpected primitive type");
355 return kDrawTriangles_DrawType;
356 }
357 }
359 // prepares clip flushes gpu state before a draw
360 bool setupClipAndFlushState(DrawType,
361 const GrDeviceCoordTexture* dstCopy,
362 GrDrawState::AutoRestoreEffects* are,
363 const SkRect* devBounds);
365 // Functions used to map clip-respecting stencil tests into normal
366 // stencil funcs supported by GPUs.
367 static GrStencilFunc ConvertStencilFunc(bool stencilInClip,
368 GrStencilFunc func);
369 static void ConvertStencilFuncAndMask(GrStencilFunc func,
370 bool clipInStencil,
371 unsigned int clipBit,
372 unsigned int userBits,
373 unsigned int* ref,
374 unsigned int* mask);
376 GrClipMaskManager fClipMaskManager;
378 struct GeometryPoolState {
379 const GrVertexBuffer* fPoolVertexBuffer;
380 int fPoolStartVertex;
382 const GrIndexBuffer* fPoolIndexBuffer;
383 int fPoolStartIndex;
384 };
385 const GeometryPoolState& getGeomPoolState() {
386 return fGeomPoolStateStack.back();
387 }
389 // The state of the scissor is controlled by the clip manager
390 struct ScissorState {
391 bool fEnabled;
392 SkIRect fRect;
393 } fScissorState;
395 // The final stencil settings to use as determined by the clip manager.
396 GrStencilSettings fStencilSettings;
398 // Helpers for setting up geometry state
399 void finalizeReservedVertices();
400 void finalizeReservedIndices();
402 private:
403 // GrDrawTarget overrides
404 virtual bool onReserveVertexSpace(size_t vertexSize, int vertexCount, void** vertices) SK_OVERRIDE;
405 virtual bool onReserveIndexSpace(int indexCount, void** indices) SK_OVERRIDE;
406 virtual void releaseReservedVertexSpace() SK_OVERRIDE;
407 virtual void releaseReservedIndexSpace() SK_OVERRIDE;
408 virtual void onSetVertexSourceToArray(const void* vertexArray, int vertexCount) SK_OVERRIDE;
409 virtual void onSetIndexSourceToArray(const void* indexArray, int indexCount) SK_OVERRIDE;
410 virtual void releaseVertexArray() SK_OVERRIDE;
411 virtual void releaseIndexArray() SK_OVERRIDE;
412 virtual void geometrySourceWillPush() SK_OVERRIDE;
413 virtual void geometrySourceWillPop(const GeometrySrcState& restoredState) SK_OVERRIDE;
416 // called when the 3D context state is unknown. Subclass should emit any
417 // assumed 3D context state and dirty any state cache.
418 virtual void onResetContext(uint32_t resetBits) = 0;
420 // overridden by backend-specific derived class to create objects.
421 virtual GrTexture* onCreateTexture(const GrTextureDesc& desc,
422 const void* srcData,
423 size_t rowBytes) = 0;
424 virtual GrTexture* onWrapBackendTexture(const GrBackendTextureDesc&) = 0;
425 virtual GrRenderTarget* onWrapBackendRenderTarget(const GrBackendRenderTargetDesc&) = 0;
426 virtual GrVertexBuffer* onCreateVertexBuffer(size_t size, bool dynamic) = 0;
427 virtual GrIndexBuffer* onCreateIndexBuffer(size_t size, bool dynamic) = 0;
428 virtual GrPath* onCreatePath(const SkPath& path, const SkStrokeRec&) = 0;
430 // overridden by backend-specific derived class to perform the clear and
431 // clearRect. NULL rect means clear whole target. If canIgnoreRect is
432 // true, it is okay to perform a full clear instead of a partial clear
433 virtual void onClear(const SkIRect* rect, GrColor color, bool canIgnoreRect) = 0;
435 // overridden by backend-specific derived class to perform the draw call.
436 virtual void onGpuDraw(const DrawInfo&) = 0;
438 // overridden by backend-specific derived class to perform the path stenciling.
439 virtual void onGpuStencilPath(const GrPath*, SkPath::FillType) = 0;
440 virtual void onGpuDrawPath(const GrPath*, SkPath::FillType) = 0;
442 // overridden by backend-specific derived class to perform flush
443 virtual void onForceRenderTargetFlush() = 0;
445 // overridden by backend-specific derived class to perform the read pixels.
446 virtual bool onReadPixels(GrRenderTarget* target,
447 int left, int top, int width, int height,
448 GrPixelConfig,
449 void* buffer,
450 size_t rowBytes) = 0;
452 // overridden by backend-specific derived class to perform the texture update
453 virtual bool onWriteTexturePixels(GrTexture* texture,
454 int left, int top, int width, int height,
455 GrPixelConfig config, const void* buffer,
456 size_t rowBytes) = 0;
458 // overridden by backend-specific derived class to perform the resolve
459 virtual void onResolveRenderTarget(GrRenderTarget* target) = 0;
461 // width and height may be larger than rt (if underlying API allows it).
462 // Should attach the SB to the RT. Returns false if compatible sb could
463 // not be created.
464 virtual bool createStencilBufferForRenderTarget(GrRenderTarget*, int width, int height) = 0;
466 // attaches an existing SB to an existing RT.
467 virtual bool attachStencilBufferToRenderTarget(GrStencilBuffer*, GrRenderTarget*) = 0;
469 // The GrGpu typically records the clients requested state and then flushes
470 // deltas from previous state at draw time. This function does the
471 // backend-specific flush of the state.
472 // returns false if current state is unsupported.
473 virtual bool flushGraphicsState(DrawType, const GrDeviceCoordTexture* dstCopy) = 0;
475 // clears the entire stencil buffer to 0
476 virtual void clearStencil() = 0;
478 // Given a rt, find or create a stencil buffer and attach it
479 bool attachStencilBufferToRenderTarget(GrRenderTarget* target);
481 // GrDrawTarget overrides
482 virtual void onDraw(const DrawInfo&) SK_OVERRIDE;
483 virtual void onStencilPath(const GrPath*, SkPath::FillType) SK_OVERRIDE;
484 virtual void onDrawPath(const GrPath*, SkPath::FillType,
485 const GrDeviceCoordTexture* dstCopy) SK_OVERRIDE;
487 // readies the pools to provide vertex/index data.
488 void prepareVertexPool();
489 void prepareIndexPool();
491 void resetContext() {
492 // We call this because the client may have messed with the
493 // stencil buffer. Perhaps we should detect whether it is a
494 // internally created stencil buffer and if so skip the invalidate.
495 fClipMaskManager.invalidateStencilMask();
496 this->onResetContext(fResetBits);
497 fResetBits = 0;
498 ++fResetTimestamp;
499 }
501 void handleDirtyContext() {
502 if (fResetBits) {
503 this->resetContext();
504 }
505 }
507 enum {
508 kPreallocGeomPoolStateStackCnt = 4,
509 };
510 typedef SkTInternalLList<GrResource> ResourceList;
511 SkSTArray<kPreallocGeomPoolStateStackCnt, GeometryPoolState, true> fGeomPoolStateStack;
512 ResetTimestamp fResetTimestamp;
513 uint32_t fResetBits;
514 GrVertexBufferAllocPool* fVertexPool;
515 GrIndexBufferAllocPool* fIndexPool;
516 // counts number of uses of vertex/index pool in the geometry stack
517 int fVertexPoolUseCnt;
518 int fIndexPoolUseCnt;
519 // these are mutable so they can be created on-demand
520 mutable GrIndexBuffer* fQuadIndexBuffer;
521 // Used to abandon/release all resources created by this GrGpu. TODO: Move this
522 // functionality to GrResourceCache.
523 ResourceList fResourceList;
525 typedef GrDrawTarget INHERITED;
526 };
528 #endif
