1 /* 2 Copyright 2010 Google Inc. 3 4 Licensed under the Apache License, Version 2.0 (the "License"); 5 you may not use this file except in compliance with the License. 6 You may obtain a copy of the License at 7 8 http://www.apache.org/licenses/LICENSE-2.0 9 10 Unless required by applicable law or agreed to in writing, software 11 distributed under the License is distributed on an "AS IS" BASIS, 12 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 See the License for the specific language governing permissions and 14 limitations under the License. 15 */ 16 17 #ifndef GrContext_DEFINED 18 #define GrContext_DEFINED 19 20 #include "GrClip.h" 21 #include "GrTextureCache.h" 22 #include "GrPaint.h" 23 #include "GrPathRenderer.h" 24 25 class GrFontCache; 26 class GrGpu; 27 struct GrGpuStats; 28 class GrVertexBufferAllocPool; 29 class GrIndexBufferAllocPool; 30 class GrInOrderDrawBuffer; 31 32 class GR_API GrContext : public GrRefCnt { 33 public: 34 /** 35 * Creates a GrContext from within a 3D context. 36 */ 37 static GrContext* Create(GrEngine engine, 38 GrPlatform3DContext context3D); 39 40 /** 41 * Helper to create a opengl-shader based context 42 */ 43 static GrContext* CreateGLShaderContext(); 44 45 virtual ~GrContext(); 46 47 /** 48 * The GrContext normally assumes that no outsider is setting state 49 * within the underlying 3D API's context/device/whatever. This call informs 50 * the context that the state was modified and it should resend. Shouldn't 51 * be called frequently for good performance. 52 */ 53 void resetContext(); 54 55 /** 56 * Abandons all gpu resources, assumes 3D API state is unknown. Call this 57 * if you have lost the associated GPU context, and thus internal texture, 58 * buffer, etc. references/IDs are now invalid. Should be called even when 59 * GrContext is no longer going to be used for two reasons: 60 * 1) ~GrContext will not try to free the objects in the 3D API. 61 * 2) If you've created GrResources that outlive the GrContext they will 62 * be marked as invalid (GrResource::isValid()) and won't attempt to 63 * free their underlying resource in the 3D API. 64 * Content drawn since the last GrContext::flush() may be lost. 65 */ 66 void contextLost(); 67 68 /** 69 * Similar to contextLost, but makes no attempt to reset state. 70 * Use this method when GrContext destruction is pending, but 71 * the graphics context is destroyed first. 72 */ 73 void contextDestroyed(); 74 75 /** 76 * Frees gpu created by the context. Can be called to reduce GPU memory 77 * pressure. 78 */ 79 void freeGpuResources(); 80 81 /////////////////////////////////////////////////////////////////////////// 82 // Textures 83 84 /** 85 * Search for an entry with the same Key. If found, "lock" it and return it. 86 * If not found, return null. 87 */ 88 GrTextureEntry* findAndLockTexture(GrTextureKey*, 89 const GrSamplerState&); 90 91 92 /** 93 * Create a new entry, based on the specified key and texture, and return 94 * its "locked" entry. 95 * 96 * Ownership of the texture is transferred to the Entry, which will unref() 97 * it when we are purged or deleted. 98 */ 99 GrTextureEntry* createAndLockTexture(GrTextureKey* key, 100 const GrSamplerState&, 101 const GrTextureDesc&, 102 void* srcData, size_t rowBytes); 103 104 /** 105 * Returns a texture matching the desc. It's contents are unknown. Subsequent 106 * requests with the same descriptor are not guaranteed to return the same 107 * texture. The same texture is guaranteed not be returned again until it is 108 * unlocked. 109 * 110 * Textures created by createAndLockTexture() hide the complications of 111 * tiling non-power-of-two textures on APIs that don't support this (e.g. 112 * unextended GLES2). Tiling a npot texture created by lockKeylessTexture on 113 * such an API will create gaps in the tiling pattern. This includes clamp 114 * mode. (This may be addressed in a future update.) 115 */ 116 GrTextureEntry* lockKeylessTexture(const GrTextureDesc& desc); 117 118 /** 119 * When done with an entry, call unlockTexture(entry) on it, which returns 120 * it to the cache, where it may be purged. 121 */ 122 void unlockTexture(GrTextureEntry* entry); 123 124 /** 125 * Creates a texture that is outside the cache. Does not count against 126 * cache's budget. 127 */ 128 GrTexture* createUncachedTexture(const GrTextureDesc&, 129 void* srcData, 130 size_t rowBytes); 131 132 /** 133 * Returns true if the specified use of an indexed texture is supported. 134 */ 135 bool supportsIndex8PixelConfig(const GrSamplerState&, int width, int height); 136 137 /** 138 * Return the current texture cache limits. 139 * 140 * @param maxTextures If non-null, returns maximum number of textures that 141 * can be held in the cache. 142 * @param maxTextureBytes If non-null, returns maximum number of bytes of 143 * texture memory that can be held in the cache. 144 */ 145 void getTextureCacheLimits(int* maxTextures, size_t* maxTextureBytes) const; 146 147 /** 148 * Specify the texture cache limits. If the current cache exceeds either 149 * of these, it will be purged (LRU) to keep the cache within these limits. 150 * 151 * @param maxTextures The maximum number of textures that can be held in 152 * the cache. 153 * @param maxTextureBytes The maximum number of bytes of texture memory 154 * that can be held in the cache. 155 */ 156 void setTextureCacheLimits(int maxTextures, size_t maxTextureBytes); 157 158 /** 159 * Return the max width or height of a texture supported by the current gpu 160 */ 161 int getMaxTextureDimension(); 162 163 /////////////////////////////////////////////////////////////////////////// 164 // Render targets 165 166 /** 167 * Sets the render target. 168 * @param target the render target to set. (should not be NULL.) 169 */ 170 void setRenderTarget(GrRenderTarget* target); 171 172 /** 173 * Gets the current render target. 174 * @return the currently bound render target. Should never be NULL. 175 */ 176 const GrRenderTarget* getRenderTarget() const; 177 GrRenderTarget* getRenderTarget(); 178 179 /////////////////////////////////////////////////////////////////////////// 180 // Platform Surfaces 181 182 // GrContext provides an interface for wrapping externally created textures 183 // and rendertargets in their Gr-equivalents. 184 185 /** 186 * Wraps an existing 3D API surface in a GrObject. desc.fFlags determines 187 * the type of object returned. If kIsTexture is set the returned object 188 * will be a GrTexture*. Otherwise, it will be a GrRenderTarget*. If both 189 * are set the render target object is accessible by 190 * GrTexture::asRenderTarget(). 191 * 192 * GL: if the object is a texture Gr may change its GL texture parameters 193 * when it is drawn. 194 * 195 * @param desc description of the object to create. 196 * @return either a GrTexture* or GrRenderTarget* depending on desc. NULL 197 * on failure. 198 */ 199 GrResource* createPlatformSurface(const GrPlatformSurfaceDesc& desc); 200 /** 201 * Reads the current target object (e.g. FBO or IDirect3DSurface9*) and 202 * viewport state from the underlying 3D API and wraps it in a 203 * GrRenderTarget. The GrRenderTarget will not attempt to delete/destroy the 204 * underlying object in its destructor and it is up to caller to guarantee 205 * that it remains valid while the GrRenderTarget is used. 206 * 207 * Will not detect that the render target is also a texture. If you need 208 * to also use the render target as a GrTexture use createPlatformSurface. 209 * 210 * @return the newly created GrRenderTarget 211 */ 212 GrRenderTarget* createRenderTargetFrom3DApiState(); 213 214 /////////////////////////////////////////////////////////////////////////// 215 // Matrix state 216 217 /** 218 * Gets the current transformation matrix. 219 * @return the current matrix. 220 */ 221 const GrMatrix& getMatrix() const; 222 223 /** 224 * Sets the transformation matrix. 225 * @param m the matrix to set. 226 */ 227 void setMatrix(const GrMatrix& m); 228 229 /** 230 * Concats the current matrix. The passed matrix is applied before the 231 * current matrix. 232 * @param m the matrix to concat. 233 */ 234 void concatMatrix(const GrMatrix& m) const; 235 236 237 /////////////////////////////////////////////////////////////////////////// 238 // Clip state 239 /** 240 * Gets the current clip. 241 * @return the current clip. 242 */ 243 const GrClip& getClip() const; 244 245 /** 246 * Sets the clip. 247 * @param clip the clip to set. 248 */ 249 void setClip(const GrClip& clip); 250 251 /** 252 * Convenience method for setting the clip to a rect. 253 * @param rect the rect to set as the new clip. 254 */ 255 void setClip(const GrIRect& rect); 256 257 /////////////////////////////////////////////////////////////////////////// 258 // Draws 259 260 /** 261 * Clear the entire or rect of the render target, ignoring any clips. 262 * @param rect the rect to clear or the whole thing if rect is NULL. 263 * @param color the color to clear to. 264 */ 265 void clear(const GrIRect* rect, GrColor color); 266 267 /** 268 * Draw everywhere (respecting the clip) with the paint. 269 */ 270 void drawPaint(const GrPaint& paint); 271 272 /** 273 * Draw the rect using a paint. 274 * @param paint describes how to color pixels. 275 * @param strokeWidth If strokeWidth < 0, then the rect is filled, else 276 * the rect is mitered stroked based on strokeWidth. If 277 * strokeWidth == 0, then the stroke is always a single 278 * pixel thick. 279 * @param matrix Optional matrix applied to the rect. Applied before 280 * context's matrix or the paint's matrix. 281 * The rects coords are used to access the paint (through texture matrix) 282 */ 283 void drawRect(const GrPaint& paint, 284 const GrRect&, 285 GrScalar strokeWidth = -1, 286 const GrMatrix* matrix = NULL); 287 288 /** 289 * Maps a rect of paint coordinates onto the a rect of destination 290 * coordinates. Each rect can optionally be transformed. The srcRect 291 * is stretched over the dstRect. The dstRect is transformed by the 292 * context's matrix and the srcRect is transformed by the paint's matrix. 293 * Additional optional matrices can be provided by parameters. 294 * 295 * @param paint describes how to color pixels. 296 * @param dstRect the destination rect to draw. 297 * @param srcRect rect of paint coordinates to be mapped onto dstRect 298 * @param dstMatrix Optional matrix to transform dstRect. Applied before 299 * context's matrix. 300 * @param srcMatrix Optional matrix to transform srcRect Applied before 301 * paint's matrix. 302 */ 303 void drawRectToRect(const GrPaint& paint, 304 const GrRect& dstRect, 305 const GrRect& srcRect, 306 const GrMatrix* dstMatrix = NULL, 307 const GrMatrix* srcMatrix = NULL); 308 309 /** 310 * Draws a path. 311 * 312 * @param paint describes how to color pixels. 313 * @param path the path to draw 314 * @param fill the path filling rule to use. 315 * @param translate optional additional translation applied to the 316 * path. 317 */ 318 void drawPath(const GrPaint& paint, const GrPath& path, GrPathFill fill, 319 const GrPoint* translate = NULL); 320 321 /** 322 * Draws vertices with a paint. 323 * 324 * @param paint describes how to color pixels. 325 * @param primitiveType primitives type to draw. 326 * @param vertexCount number of vertices. 327 * @param positions array of vertex positions, required. 328 * @param texCoords optional array of texture coordinates used 329 * to access the paint. 330 * @param colors optional array of per-vertex colors, supercedes 331 * the paint's color field. 332 * @param indices optional array of indices. If NULL vertices 333 * are drawn non-indexed. 334 * @param indexCount if indices is non-null then this is the 335 * number of indices. 336 */ 337 void drawVertices(const GrPaint& paint, 338 GrPrimitiveType primitiveType, 339 int vertexCount, 340 const GrPoint positions[], 341 const GrPoint texs[], 342 const GrColor colors[], 343 const uint16_t indices[], 344 int indexCount); 345 346 /** 347 * Similar to drawVertices but caller provides objects that convert to Gr 348 * types. The count of vertices is given by posSrc. 349 * 350 * @param paint describes how to color pixels. 351 * @param primitiveType primitives type to draw. 352 * @param posSrc Source of vertex positions. Must implement 353 * int count() const; 354 * void writeValue(int i, GrPoint* point) const; 355 * count returns the total number of vertices and 356 * writeValue writes a vertex position to point. 357 * @param texSrc optional, pass NULL to not use explicit tex 358 * coords. If present provides tex coords with 359 * method: 360 * void writeValue(int i, GrPoint* point) const; 361 * @param texSrc optional, pass NULL to not use per-vertex colors 362 * If present provides colors with method: 363 * void writeValue(int i, GrColor* point) const; 364 * @param indices optional, pass NULL for non-indexed drawing. If 365 * present supplies indices for indexed drawing 366 * with following methods: 367 * int count() const; 368 * void writeValue(int i, uint16_t* point) const; 369 * count returns the number of indices and 370 * writeValue supplies each index. 371 */ 372 template <typename POS_SRC, 373 typename TEX_SRC, 374 typename COL_SRC, 375 typename IDX_SRC> 376 void drawCustomVertices(const GrPaint& paint, 377 GrPrimitiveType primitiveType, 378 const POS_SRC& posSrc, 379 const TEX_SRC* texCoordSrc, 380 const COL_SRC* colorSrc, 381 const IDX_SRC* idxSrc); 382 /** 383 * To avoid the problem of having to create a typename for NULL parameters, 384 * these reduced versions of drawCustomVertices are provided. 385 */ 386 template <typename POS_SRC> 387 void drawCustomVertices(const GrPaint& paint, 388 GrPrimitiveType primitiveType, 389 const POS_SRC& posSrc); 390 template <typename POS_SRC, typename TEX_SRC> 391 void drawCustomVertices(const GrPaint& paint, 392 GrPrimitiveType primitiveType, 393 const POS_SRC& posSrc, 394 const TEX_SRC* texCoordSrc); 395 template <typename POS_SRC, typename TEX_SRC, typename COL_SRC> 396 void drawCustomVertices(const GrPaint& paint, 397 GrPrimitiveType primitiveType, 398 const POS_SRC& posSrc, 399 const TEX_SRC* texCoordSrc, 400 const COL_SRC* colorSrc); 401 402 403 /////////////////////////////////////////////////////////////////////////// 404 // Misc. 405 406 /** 407 * Flags that affect flush() behavior. 408 */ 409 enum FlushBits { 410 /** 411 * A client may want Gr to bind a GrRenderTarget in the 3D API so that 412 * it can be rendered to directly. However, Gr lazily sets state. Simply 413 * calling setRenderTarget() followed by flush() without flags may not 414 * bind the render target. This flag forces the context to bind the last 415 * set render target in the 3D API. 416 */ 417 kForceCurrentRenderTarget_FlushBit = 0x1, 418 /** 419 * A client may reach a point where it has partially rendered a frame 420 * through a GrContext that it knows the user will never see. This flag 421 * causes the flush to skip submission of deferred content to the 3D API 422 * during the flush. 423 */ 424 kDiscard_FlushBit = 0x2, 425 }; 426 427 /** 428 * Call to ensure all drawing to the context has been issued to the 429 * underlying 3D API. 430 * @param flagsBitfield flags that control the flushing behavior. See 431 * FlushBits. 432 */ 433 void flush(int flagsBitfield = 0); 434 435 /** 436 * Reads a rectangle of pixels from a render target. 437 * @param renderTarget the render target to read from. NULL means the 438 * current render target. 439 * @param left left edge of the rectangle to read (inclusive) 440 * @param top top edge of the rectangle to read (inclusive) 441 * @param width width of rectangle to read in pixels. 442 * @param height height of rectangle to read in pixels. 443 * @param config the pixel config of the destination buffer 444 * @param buffer memory to read the rectangle into. 445 * 446 * @return true if the read succeeded, false if not. The read can fail 447 * because of a unsupported pixel config or because no render 448 * target is currently set. 449 */ 450 bool readRenderTargetPixels(GrRenderTarget* target, 451 int left, int top, int width, int height, 452 GrPixelConfig config, void* buffer); 453 454 /** 455 * Reads a rectangle of pixels from a texture. 456 * @param texture the render target to read from. 457 * @param left left edge of the rectangle to read (inclusive) 458 * @param top top edge of the rectangle to read (inclusive) 459 * @param width width of rectangle to read in pixels. 460 * @param height height of rectangle to read in pixels. 461 * @param config the pixel config of the destination buffer 462 * @param buffer memory to read the rectangle into. 463 * 464 * @return true if the read succeeded, false if not. The read can fail 465 * because of a unsupported pixel config. 466 */ 467 bool readTexturePixels(GrTexture* target, 468 int left, int top, int width, int height, 469 GrPixelConfig config, void* buffer); 470 471 /** 472 * Copy the src pixels [buffer, stride, pixelconfig] into the current 473 * render-target at the specified rectangle. 474 */ 475 void writePixels(int left, int top, int width, int height, 476 GrPixelConfig, const void* buffer, size_t stride); 477 478 /////////////////////////////////////////////////////////////////////////// 479 // Helpers 480 481 class AutoRenderTarget : ::GrNoncopyable { 482 public: 483 AutoRenderTarget(GrContext* context, GrRenderTarget* target) { 484 fContext = NULL; 485 fPrevTarget = context->getRenderTarget(); 486 if (fPrevTarget != target) { 487 context->setRenderTarget(target); 488 fContext = context; 489 } 490 } 491 ~AutoRenderTarget() { 492 if (fContext) { 493 fContext->setRenderTarget(fPrevTarget); 494 } 495 } 496 private: 497 GrContext* fContext; 498 GrRenderTarget* fPrevTarget; 499 }; 500 501 502 /////////////////////////////////////////////////////////////////////////// 503 // Functions intended for internal use only. 504 GrGpu* getGpu() { return fGpu; } 505 GrFontCache* getFontCache() { return fFontCache; } 506 GrDrawTarget* getTextTarget(const GrPaint& paint); 507 void flushText(); 508 const GrIndexBuffer* getQuadIndexBuffer() const; 509 void resetStats(); 510 const GrGpuStats& getStats() const; 511 void printStats() const; 512 513 private: 514 // used to keep track of when we need to flush the draw buffer 515 enum DrawCategory { 516 kBuffered_DrawCategory, // last draw was inserted in draw buffer 517 kUnbuffered_DrawCategory, // last draw was not inserted in the draw buffer 518 kText_DrawCategory // text context was last to draw 519 }; 520 DrawCategory fLastDrawCategory; 521 522 GrGpu* fGpu; 523 GrTextureCache* fTextureCache; 524 GrFontCache* fFontCache; 525 526 GrPathRenderer* fCustomPathRenderer; 527 GrDefaultPathRenderer fDefaultPathRenderer; 528 529 GrVertexBufferAllocPool* fDrawBufferVBAllocPool; 530 GrIndexBufferAllocPool* fDrawBufferIBAllocPool; 531 GrInOrderDrawBuffer* fDrawBuffer; 532 533 GrIndexBuffer* fAAFillRectIndexBuffer; 534 GrIndexBuffer* fAAStrokeRectIndexBuffer; 535 536 GrContext(GrGpu* gpu); 537 538 void fillAARect(GrDrawTarget* target, 539 const GrPaint& paint, 540 const GrRect& devRect); 541 542 void strokeAARect(GrDrawTarget* target, 543 const GrPaint& paint, 544 const GrRect& devRect, 545 const GrVec& devStrokeSize); 546 547 inline int aaFillRectIndexCount() const; 548 GrIndexBuffer* aaFillRectIndexBuffer(); 549 550 inline int aaStrokeRectIndexCount() const; 551 GrIndexBuffer* aaStrokeRectIndexBuffer(); 552 553 void setupDrawBuffer(); 554 555 void flushDrawBuffer(); 556 557 static void SetPaint(const GrPaint& paint, GrDrawTarget* target); 558 559 bool finalizeTextureKey(GrTextureKey*, 560 const GrSamplerState&, 561 bool keyless) const; 562 563 GrDrawTarget* prepareToDraw(const GrPaint& paint, DrawCategory drawType); 564 565 void drawClipIntoStencil(); 566 567 GrPathRenderer* getPathRenderer(const GrDrawTarget*, const GrPath&, GrPathFill); 568 569 struct OffscreenRecord; 570 571 bool doOffscreenAA(GrDrawTarget* target, 572 const GrPaint& paint, 573 bool isLines) const; 574 575 // sets up target to draw coverage to the supersampled render target 576 bool setupOffscreenAAPass1(GrDrawTarget* target, 577 bool requireStencil, 578 const GrIRect& boundRect, 579 OffscreenRecord* record); 580 581 // sets up target to sample coverage of supersampled render target back 582 // to the main render target using stage kOffscreenStage. 583 void offscreenAAPass2(GrDrawTarget* target, 584 const GrPaint& paint, 585 const GrIRect& boundRect, 586 OffscreenRecord* record); 587 588 // computes vertex layout bits based on the paint. If paint expresses 589 // a texture for a stage, the stage coords will be bound to postitions 590 // unless hasTexCoords[s]==true in which case stage s's input coords 591 // are bound to tex coord index s. hasTexCoords == NULL is a shortcut 592 // for an array where all the values are false. 593 static int PaintStageVertexLayoutBits( 594 const GrPaint& paint, 595 const bool hasTexCoords[GrPaint::kTotalStages]); 596 597 }; 598 599 /** 600 * Save/restore the view-matrix in the context. 601 */ 602 class GrAutoMatrix : GrNoncopyable { 603 public: 604 GrAutoMatrix(GrContext* ctx) : fContext(ctx) { 605 fMatrix = ctx->getMatrix(); 606 } 607 GrAutoMatrix(GrContext* ctx, const GrMatrix& matrix) : fContext(ctx) { 608 fMatrix = ctx->getMatrix(); 609 ctx->setMatrix(matrix); 610 } 611 ~GrAutoMatrix() { 612 fContext->setMatrix(fMatrix); 613 } 614 615 private: 616 GrContext* fContext; 617 GrMatrix fMatrix; 618 }; 619 620 #endif 621 622 #include "GrContext_impl.h" 623 624
