GrDrawTarget.cpp revision 8b39f8f2bcbcd5f95908c34edb3cc70816c949b0 
1
2/*
3 * Copyright 2010 Google Inc.
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8
9
10
11#include "GrDrawTarget.h"
12#include "GrGpuVertex.h"
13#include "GrIndexBuffer.h"
14#include "GrRenderTarget.h"
15#include "GrTexture.h"
16#include "GrVertexBuffer.h"
17
18namespace {
19
20/**
21 * This function generates some masks that we like to have known at compile
22 * time. When the number of stages or tex coords is bumped or the way bits
23 * are defined in GrDrawTarget.h changes this funcion should be rerun to
24 * generate the new masks. (We attempted to force the compiler to generate the
25 * masks using recursive templates but always wound up with static initializers
26 * under gcc, even if they were just a series of immediate->memory moves.)
27 *
28 */
29void gen_mask_arrays(GrVertexLayout* stageTexCoordMasks,
30                     GrVertexLayout* stageMasks,
31                     GrVertexLayout* texCoordMasks) {
32    for (int s = 0; s < GrDrawState::kNumStages; ++s) {
33        stageTexCoordMasks[s] = 0;
34        for (int t = 0; t < GrDrawState::kMaxTexCoords; ++t) {
35            stageTexCoordMasks[s] |= GrDrawTarget::StageTexCoordVertexLayoutBit(s, t);
36        }
37        stageMasks[s] = stageTexCoordMasks[s] | GrDrawTarget::StagePosAsTexCoordVertexLayoutBit(s);
38    }
39    for (int t = 0; t < GrDrawState::kMaxTexCoords; ++t) {
40        texCoordMasks[t] = 0;
41        for (int s = 0; s < GrDrawState::kNumStages; ++s) {
42            texCoordMasks[t] |= GrDrawTarget::StageTexCoordVertexLayoutBit(s, t);
43        }
44    }
45}
46
47/**
48 * Run this function to generate the code that declares the global masks.
49 */
50void gen_globals() {
51    GrVertexLayout stageTexCoordMasks[GrDrawState::kNumStages];
52    GrVertexLayout stageMasks[GrDrawState::kNumStages];
53    GrVertexLayout texCoordMasks[GrDrawState::kMaxTexCoords];
54    gen_mask_arrays(stageTexCoordMasks, stageMasks, texCoordMasks);
55
56    GrPrintf("const GrVertexLayout gStageTexCoordMasks[] = {\n");
57    for (int s = 0; s < GrDrawState::kNumStages; ++s) {
58        GrPrintf("    0x%x,\n", stageTexCoordMasks[s]);
59    }
60    GrPrintf("};\n");
61    GrPrintf("GR_STATIC_ASSERT(GrDrawState::kNumStages == GR_ARRAY_COUNT(gStageTexCoordMasks));\n\n");
62    GrPrintf("const GrVertexLayout gStageMasks[] = {\n");
63    for (int s = 0; s < GrDrawState::kNumStages; ++s) {
64        GrPrintf("    0x%x,\n", stageMasks[s]);
65    }
66    GrPrintf("};\n");
67    GrPrintf("GR_STATIC_ASSERT(GrDrawState::kNumStages == GR_ARRAY_COUNT(gStageMasks));\n\n");
68    GrPrintf("const GrVertexLayout gTexCoordMasks[] = {\n");
69    for (int t = 0; t < GrDrawState::kMaxTexCoords; ++t) {
70        GrPrintf("    0x%x,\n", texCoordMasks[t]);
71    }
72    GrPrintf("};\n");
73    GrPrintf("GR_STATIC_ASSERT(GrDrawState::kMaxTexCoords == GR_ARRAY_COUNT(gTexCoordMasks));\n");
74}
75
76/* These values were generated by the above function */
77const GrVertexLayout gStageTexCoordMasks[] = {
78    0x49,
79    0x92,
80    0x124
81};
82
83GR_STATIC_ASSERT(GrDrawState::kNumStages == GR_ARRAY_COUNT(gStageTexCoordMasks));
84const GrVertexLayout gStageMasks[] = {
85    0x249,
86    0x492,
87    0x924
88};
89
90GR_STATIC_ASSERT(GrDrawState::kNumStages == GR_ARRAY_COUNT(gStageMasks));
91const GrVertexLayout gTexCoordMasks[] = {
92    0x7,
93    0x38,
94    0x1c0,
95};
96GR_STATIC_ASSERT(GrDrawState::kMaxTexCoords == GR_ARRAY_COUNT(gTexCoordMasks));
97
98bool check_layout(GrVertexLayout layout) {
99    // can only have 1 or 0 bits set for each stage.
100    for (int s = 0; s < GrDrawState::kNumStages; ++s) {
101        int stageBits = layout & gStageMasks[s];
102        if (stageBits && !GrIsPow2(stageBits)) {
103            return false;
104        }
105    }
106    return true;
107}
108
109int num_tex_coords(GrVertexLayout layout) {
110    int cnt = 0;
111    // figure out how many tex coordinates are present
112    for (int t = 0; t < GrDrawState::kMaxTexCoords; ++t) {
113        if (gTexCoordMasks[t] & layout) {
114            ++cnt;
115        }
116    }
117    return cnt;
118}
119
120} //unnamed namespace
121
122size_t GrDrawTarget::VertexSize(GrVertexLayout vertexLayout) {
123    GrAssert(check_layout(vertexLayout));
124
125    size_t vecSize = (vertexLayout & kTextFormat_VertexLayoutBit) ?
126                        sizeof(GrGpuTextVertex) :
127                        sizeof(GrPoint);
128
129    size_t size = vecSize; // position
130    size += num_tex_coords(vertexLayout) * vecSize;
131    if (vertexLayout & kColor_VertexLayoutBit) {
132        size += sizeof(GrColor);
133    }
134    if (vertexLayout & kCoverage_VertexLayoutBit) {
135        size += sizeof(GrColor);
136    }
137    if (vertexLayout & kEdge_VertexLayoutBit) {
138        size += 4 * sizeof(GrScalar);
139    }
140    return size;
141}
142
143////////////////////////////////////////////////////////////////////////////////
144
145/**
146 * Functions for computing offsets of various components from the layout
147 * bitfield.
148 *
149 * Order of vertex components:
150 * Position
151 * Tex Coord 0
152 * ...
153 * Tex Coord GrDrawState::kMaxTexCoords-1
154 * Color
155 * Coverage
156 */
157
158int GrDrawTarget::VertexStageCoordOffset(int stage, GrVertexLayout vertexLayout) {
159    GrAssert(check_layout(vertexLayout));
160    if (StagePosAsTexCoordVertexLayoutBit(stage) & vertexLayout) {
161        return 0;
162    }
163    int tcIdx = VertexTexCoordsForStage(stage, vertexLayout);
164    if (tcIdx >= 0) {
165
166        int vecSize = (vertexLayout & kTextFormat_VertexLayoutBit) ?
167                                    sizeof(GrGpuTextVertex) :
168                                    sizeof(GrPoint);
169        int offset = vecSize; // position
170        // figure out how many tex coordinates are present and precede this one.
171        for (int t = 0; t < tcIdx; ++t) {
172            if (gTexCoordMasks[t] & vertexLayout) {
173                offset += vecSize;
174            }
175        }
176        return offset;
177    }
178
179    return -1;
180}
181
182int GrDrawTarget::VertexColorOffset(GrVertexLayout vertexLayout) {
183    GrAssert(check_layout(vertexLayout));
184
185    if (vertexLayout & kColor_VertexLayoutBit) {
186        int vecSize = (vertexLayout & kTextFormat_VertexLayoutBit) ?
187                                    sizeof(GrGpuTextVertex) :
188                                    sizeof(GrPoint);
189        return vecSize * (num_tex_coords(vertexLayout) + 1); //+1 for pos
190    }
191    return -1;
192}
193
194int GrDrawTarget::VertexCoverageOffset(GrVertexLayout vertexLayout) {
195    GrAssert(check_layout(vertexLayout));
196
197    if (vertexLayout & kCoverage_VertexLayoutBit) {
198        int vecSize = (vertexLayout & kTextFormat_VertexLayoutBit) ?
199                                    sizeof(GrGpuTextVertex) :
200                                    sizeof(GrPoint);
201
202        int offset = vecSize * (num_tex_coords(vertexLayout) + 1);
203        if (vertexLayout & kColor_VertexLayoutBit) {
204            offset += sizeof(GrColor);
205        }
206        return offset;
207    }
208    return -1;
209}
210
211int GrDrawTarget::VertexEdgeOffset(GrVertexLayout vertexLayout) {
212    GrAssert(check_layout(vertexLayout));
213
214    // edge pts are after the pos, tex coords, and color
215    if (vertexLayout & kEdge_VertexLayoutBit) {
216        int vecSize = (vertexLayout & kTextFormat_VertexLayoutBit) ?
217                                    sizeof(GrGpuTextVertex) :
218                                    sizeof(GrPoint);
219        int offset = vecSize * (num_tex_coords(vertexLayout) + 1); //+1 for pos
220        if (vertexLayout & kColor_VertexLayoutBit) {
221            offset += sizeof(GrColor);
222        }
223        if (vertexLayout & kCoverage_VertexLayoutBit) {
224            offset += sizeof(GrColor);
225        }
226        return offset;
227    }
228    return -1;
229}
230
231int GrDrawTarget::VertexSizeAndOffsetsByIdx(
232        GrVertexLayout vertexLayout,
233        int texCoordOffsetsByIdx[GrDrawState::kMaxTexCoords],
234        int* colorOffset,
235        int* coverageOffset,
236        int* edgeOffset) {
237    GrAssert(check_layout(vertexLayout));
238
239    int vecSize = (vertexLayout & kTextFormat_VertexLayoutBit) ?
240                                                    sizeof(GrGpuTextVertex) :
241                                                    sizeof(GrPoint);
242    int size = vecSize; // position
243
244    for (int t = 0; t < GrDrawState::kMaxTexCoords; ++t) {
245        if (gTexCoordMasks[t] & vertexLayout) {
246            if (NULL != texCoordOffsetsByIdx) {
247                texCoordOffsetsByIdx[t] = size;
248            }
249            size += vecSize;
250        } else {
251            if (NULL != texCoordOffsetsByIdx) {
252                texCoordOffsetsByIdx[t] = -1;
253            }
254        }
255    }
256    if (kColor_VertexLayoutBit & vertexLayout) {
257        if (NULL != colorOffset) {
258            *colorOffset = size;
259        }
260        size += sizeof(GrColor);
261    } else {
262        if (NULL != colorOffset) {
263            *colorOffset = -1;
264        }
265    }
266    if (kCoverage_VertexLayoutBit & vertexLayout) {
267        if (NULL != coverageOffset) {
268            *coverageOffset = size;
269        }
270        size += sizeof(GrColor);
271    } else {
272        if (NULL != coverageOffset) {
273            *coverageOffset = -1;
274        }
275    }
276    if (kEdge_VertexLayoutBit & vertexLayout) {
277        if (NULL != edgeOffset) {
278            *edgeOffset = size;
279        }
280        size += 4 * sizeof(GrScalar);
281    } else {
282        if (NULL != edgeOffset) {
283            *edgeOffset = -1;
284        }
285    }
286    return size;
287}
288
289int GrDrawTarget::VertexSizeAndOffsetsByStage(
290        GrVertexLayout vertexLayout,
291        int texCoordOffsetsByStage[GrDrawState::kNumStages],
292        int* colorOffset,
293        int* coverageOffset,
294        int* edgeOffset) {
295    GrAssert(check_layout(vertexLayout));
296
297    int texCoordOffsetsByIdx[GrDrawState::kMaxTexCoords];
298    int size = VertexSizeAndOffsetsByIdx(vertexLayout,
299                                         (NULL == texCoordOffsetsByStage) ?
300                                               NULL :
301                                               texCoordOffsetsByIdx,
302                                         colorOffset,
303                                         coverageOffset,
304                                         edgeOffset);
305    if (NULL != texCoordOffsetsByStage) {
306        for (int s = 0; s < GrDrawState::kNumStages; ++s) {
307            int tcIdx;
308            if (StagePosAsTexCoordVertexLayoutBit(s) & vertexLayout) {
309                texCoordOffsetsByStage[s] = 0;
310            } else if ((tcIdx = VertexTexCoordsForStage(s, vertexLayout)) >= 0) {
311                texCoordOffsetsByStage[s] = texCoordOffsetsByIdx[tcIdx];
312            } else {
313                texCoordOffsetsByStage[s] = -1;
314            }
315        }
316    }
317    return size;
318}
319
320////////////////////////////////////////////////////////////////////////////////
321
322bool GrDrawTarget::VertexUsesStage(int stage, GrVertexLayout vertexLayout) {
323    GrAssert(stage < GrDrawState::kNumStages);
324    GrAssert(check_layout(vertexLayout));
325    return !!(gStageMasks[stage] & vertexLayout);
326}
327
328bool GrDrawTarget::VertexUsesTexCoordIdx(int coordIndex,
329                                         GrVertexLayout vertexLayout) {
330    GrAssert(coordIndex < GrDrawState::kMaxTexCoords);
331    GrAssert(check_layout(vertexLayout));
332    return !!(gTexCoordMasks[coordIndex] & vertexLayout);
333}
334
335int GrDrawTarget::VertexTexCoordsForStage(int stage,
336                                          GrVertexLayout vertexLayout) {
337    GrAssert(stage < GrDrawState::kNumStages);
338    GrAssert(check_layout(vertexLayout));
339    int bit = vertexLayout & gStageTexCoordMasks[stage];
340    if (bit) {
341        // figure out which set of texture coordates is used
342        // bits are ordered T0S0, T0S1, T0S2, ..., T1S0, T1S1, ...
343        // and start at bit 0.
344        GR_STATIC_ASSERT(sizeof(GrVertexLayout) <= sizeof(uint32_t));
345        return (32 - Gr_clz(bit) - 1) / GrDrawState::kNumStages;
346    }
347    return -1;
348}
349
350////////////////////////////////////////////////////////////////////////////////
351
352void GrDrawTarget::VertexLayoutUnitTest() {
353    // Ensure that our globals mask arrays are correct
354    GrVertexLayout stageTexCoordMasks[GrDrawState::kNumStages];
355    GrVertexLayout stageMasks[GrDrawState::kNumStages];
356    GrVertexLayout texCoordMasks[GrDrawState::kMaxTexCoords];
357    gen_mask_arrays(stageTexCoordMasks, stageMasks, texCoordMasks);
358    for (int s = 0; s < GrDrawState::kNumStages; ++s) {
359        GrAssert(stageTexCoordMasks[s] == gStageTexCoordMasks[s]);
360        GrAssert(stageMasks[s] == gStageMasks[s]);
361    }
362    for (int t = 0; t < GrDrawState::kMaxTexCoords; ++t) {
363        GrAssert(texCoordMasks[t] == gTexCoordMasks[t]);
364    }
365
366    // not necessarily exhaustive
367    static bool run;
368    if (!run) {
369        run = true;
370        for (int s = 0; s < GrDrawState::kNumStages; ++s) {
371
372            GrAssert(!VertexUsesStage(s, 0));
373            GrAssert(-1 == VertexStageCoordOffset(s, 0));
374            GrVertexLayout stageMask = 0;
375            for (int t = 0; t < GrDrawState::kMaxTexCoords; ++t) {
376                stageMask |= StageTexCoordVertexLayoutBit(s,t);
377            }
378            GrAssert(1 == GrDrawState::kMaxTexCoords ||
379                     !check_layout(stageMask));
380            GrAssert(gStageTexCoordMasks[s] == stageMask);
381            stageMask |= StagePosAsTexCoordVertexLayoutBit(s);
382            GrAssert(gStageMasks[s] == stageMask);
383            GrAssert(!check_layout(stageMask));
384        }
385        for (int t = 0; t < GrDrawState::kMaxTexCoords; ++t) {
386            GrVertexLayout tcMask = 0;
387            GrAssert(!VertexUsesTexCoordIdx(t, 0));
388            for (int s = 0; s < GrDrawState::kNumStages; ++s) {
389                tcMask |= StageTexCoordVertexLayoutBit(s,t);
390                GrAssert(VertexUsesStage(s, tcMask));
391                GrAssert(sizeof(GrPoint) == VertexStageCoordOffset(s, tcMask));
392                GrAssert(VertexUsesTexCoordIdx(t, tcMask));
393                GrAssert(2*sizeof(GrPoint) == VertexSize(tcMask));
394                GrAssert(t == VertexTexCoordsForStage(s, tcMask));
395                for (int s2 = s + 1; s2 < GrDrawState::kNumStages; ++s2) {
396                    GrAssert(-1 == VertexStageCoordOffset(s2, tcMask));
397                    GrAssert(!VertexUsesStage(s2, tcMask));
398                    GrAssert(-1 == VertexTexCoordsForStage(s2, tcMask));
399
400                #if GR_DEBUG
401                    GrVertexLayout posAsTex = tcMask | StagePosAsTexCoordVertexLayoutBit(s2);
402                #endif
403                    GrAssert(0 == VertexStageCoordOffset(s2, posAsTex));
404                    GrAssert(VertexUsesStage(s2, posAsTex));
405                    GrAssert(2*sizeof(GrPoint) == VertexSize(posAsTex));
406                    GrAssert(-1 == VertexTexCoordsForStage(s2, posAsTex));
407                    GrAssert(-1 == VertexEdgeOffset(posAsTex));
408                }
409                GrAssert(-1 == VertexEdgeOffset(tcMask));
410                GrAssert(-1 == VertexColorOffset(tcMask));
411                GrAssert(-1 == VertexCoverageOffset(tcMask));
412            #if GR_DEBUG
413                GrVertexLayout withColor = tcMask | kColor_VertexLayoutBit;
414            #endif
415                GrAssert(-1 == VertexCoverageOffset(withColor));
416                GrAssert(2*sizeof(GrPoint) == VertexColorOffset(withColor));
417                GrAssert(2*sizeof(GrPoint) + sizeof(GrColor) == VertexSize(withColor));
418            #if GR_DEBUG
419                GrVertexLayout withEdge = tcMask | kEdge_VertexLayoutBit;
420            #endif
421                GrAssert(-1 == VertexColorOffset(withEdge));
422                GrAssert(2*sizeof(GrPoint) == VertexEdgeOffset(withEdge));
423                GrAssert(4*sizeof(GrPoint) == VertexSize(withEdge));
424            #if GR_DEBUG
425                GrVertexLayout withColorAndEdge = withColor | kEdge_VertexLayoutBit;
426            #endif
427                GrAssert(2*sizeof(GrPoint) == VertexColorOffset(withColorAndEdge));
428                GrAssert(2*sizeof(GrPoint) + sizeof(GrColor) == VertexEdgeOffset(withColorAndEdge));
429                GrAssert(4*sizeof(GrPoint) + sizeof(GrColor) == VertexSize(withColorAndEdge));
430            #if GR_DEBUG
431                GrVertexLayout withCoverage = tcMask | kCoverage_VertexLayoutBit;
432            #endif
433                GrAssert(-1 == VertexColorOffset(withCoverage));
434                GrAssert(2*sizeof(GrPoint) == VertexCoverageOffset(withCoverage));
435                GrAssert(2*sizeof(GrPoint) + sizeof(GrColor) == VertexSize(withCoverage));
436            #if GR_DEBUG
437                GrVertexLayout withCoverageAndColor = tcMask | kCoverage_VertexLayoutBit |
438                                                      kColor_VertexLayoutBit;
439            #endif
440                GrAssert(2*sizeof(GrPoint) == VertexColorOffset(withCoverageAndColor));
441                GrAssert(2*sizeof(GrPoint) + sizeof(GrColor) == VertexCoverageOffset(withCoverageAndColor));
442                GrAssert(2*sizeof(GrPoint) + 2 * sizeof(GrColor) == VertexSize(withCoverageAndColor));
443            }
444            GrAssert(gTexCoordMasks[t] == tcMask);
445            GrAssert(check_layout(tcMask));
446
447            int stageOffsets[GrDrawState::kNumStages];
448            int colorOffset;
449            int edgeOffset;
450            int coverageOffset;
451            int size;
452            size = VertexSizeAndOffsetsByStage(tcMask,
453                                               stageOffsets, &colorOffset,
454                                               &coverageOffset, &edgeOffset);
455            GrAssert(2*sizeof(GrPoint) == size);
456            GrAssert(-1 == colorOffset);
457            GrAssert(-1 == coverageOffset);
458            GrAssert(-1 == edgeOffset);
459            for (int s = 0; s < GrDrawState::kNumStages; ++s) {
460                GrAssert(VertexUsesStage(s, tcMask));
461                GrAssert(sizeof(GrPoint) == stageOffsets[s]);
462                GrAssert(sizeof(GrPoint) == VertexStageCoordOffset(s, tcMask));
463            }
464        }
465    }
466}
467
468////////////////////////////////////////////////////////////////////////////////
469
470#define DEBUG_INVAL_BUFFER 0xdeadcafe
471#define DEBUG_INVAL_START_IDX -1
472
473GrDrawTarget::GrDrawTarget() {
474#if GR_DEBUG
475    VertexLayoutUnitTest();
476#endif
477    GeometrySrcState& geoSrc = fGeoSrcStateStack.push_back();
478#if GR_DEBUG
479    geoSrc.fVertexCount = DEBUG_INVAL_START_IDX;
480    geoSrc.fVertexBuffer = (GrVertexBuffer*)DEBUG_INVAL_BUFFER;
481    geoSrc.fIndexCount = DEBUG_INVAL_START_IDX;
482    geoSrc.fIndexBuffer = (GrIndexBuffer*)DEBUG_INVAL_BUFFER;
483#endif
484    geoSrc.fVertexSrc = kNone_GeometrySrcType;
485    geoSrc.fIndexSrc  = kNone_GeometrySrcType;
486}
487
488GrDrawTarget::~GrDrawTarget() {
489    GrAssert(1 == fGeoSrcStateStack.count());
490    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
491    GrAssert(kNone_GeometrySrcType == geoSrc.fIndexSrc);
492    GrAssert(kNone_GeometrySrcType == geoSrc.fVertexSrc);
493}
494
495void GrDrawTarget::releaseGeometry() {
496    int popCnt = fGeoSrcStateStack.count() - 1;
497    while (popCnt) {
498        this->popGeometrySource();
499        --popCnt;
500    }
501    this->resetVertexSource();
502    this->resetIndexSource();
503}
504
505void GrDrawTarget::setClip(const GrClip& clip) {
506    clipWillBeSet(clip);
507    fClip = clip;
508}
509
510const GrClip& GrDrawTarget::getClip() const {
511    return fClip;
512}
513
514void GrDrawTarget::saveCurrentDrawState(SavedDrawState* state) const {
515    state->fState = fCurrDrawState;
516}
517
518void GrDrawTarget::restoreDrawState(const SavedDrawState& state) {
519    fCurrDrawState = state.fState;
520}
521
522void GrDrawTarget::copyDrawState(const GrDrawTarget& srcTarget) {
523    fCurrDrawState = srcTarget.fCurrDrawState;
524}
525
526bool GrDrawTarget::reserveVertexSpace(GrVertexLayout vertexLayout,
527                                      int vertexCount,
528                                      void** vertices) {
529    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
530    bool acquired = false;
531    if (vertexCount > 0) {
532        GrAssert(NULL != vertices);
533        this->releasePreviousVertexSource();
534        geoSrc.fVertexSrc = kNone_GeometrySrcType;
535
536        acquired = this->onReserveVertexSpace(vertexLayout,
537                                              vertexCount,
538                                              vertices);
539    }
540    if (acquired) {
541        geoSrc.fVertexSrc = kReserved_GeometrySrcType;
542        geoSrc.fVertexCount = vertexCount;
543        geoSrc.fVertexLayout = vertexLayout;
544    } else if (NULL != vertices) {
545        *vertices = NULL;
546    }
547    return acquired;
548}
549
550bool GrDrawTarget::reserveIndexSpace(int indexCount,
551                                     void** indices) {
552    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
553    bool acquired = false;
554    if (indexCount > 0) {
555        GrAssert(NULL != indices);
556        this->releasePreviousIndexSource();
557        geoSrc.fIndexSrc = kNone_GeometrySrcType;
558
559        acquired = this->onReserveIndexSpace(indexCount, indices);
560    }
561    if (acquired) {
562        geoSrc.fIndexSrc = kReserved_GeometrySrcType;
563        geoSrc.fIndexCount = indexCount;
564    } else if (NULL != indices) {
565        *indices = NULL;
566    }
567    return acquired;
568
569}
570
571bool GrDrawTarget::geometryHints(GrVertexLayout vertexLayout,
572                                 int32_t* vertexCount,
573                                 int32_t* indexCount) const {
574    if (NULL != vertexCount) {
575        *vertexCount = -1;
576    }
577    if (NULL != indexCount) {
578        *indexCount = -1;
579    }
580    return false;
581}
582
583void GrDrawTarget::releasePreviousVertexSource() {
584    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
585    switch (geoSrc.fVertexSrc) {
586        case kNone_GeometrySrcType:
587            break;
588        case kArray_GeometrySrcType:
589            this->releaseVertexArray();
590            break;
591        case kReserved_GeometrySrcType:
592            this->releaseReservedVertexSpace();
593            break;
594        case kBuffer_GeometrySrcType:
595            geoSrc.fVertexBuffer->unref();
596#if GR_DEBUG
597            geoSrc.fVertexBuffer = (GrVertexBuffer*)DEBUG_INVAL_BUFFER;
598#endif
599            break;
600        default:
601            GrCrash("Unknown Vertex Source Type.");
602            break;
603    }
604}
605
606void GrDrawTarget::releasePreviousIndexSource() {
607    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
608    switch (geoSrc.fIndexSrc) {
609        case kNone_GeometrySrcType:   // these two don't require
610            break;
611        case kArray_GeometrySrcType:
612            this->releaseIndexArray();
613            break;
614        case kReserved_GeometrySrcType:
615            this->releaseReservedIndexSpace();
616            break;
617        case kBuffer_GeometrySrcType:
618            geoSrc.fIndexBuffer->unref();
619#if GR_DEBUG
620            geoSrc.fIndexBuffer = (GrIndexBuffer*)DEBUG_INVAL_BUFFER;
621#endif
622            break;
623        default:
624            GrCrash("Unknown Index Source Type.");
625            break;
626    }
627}
628
629void GrDrawTarget::setVertexSourceToArray(GrVertexLayout vertexLayout,
630                                          const void* vertexArray,
631                                          int vertexCount) {
632    this->releasePreviousVertexSource();
633    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
634    geoSrc.fVertexSrc = kArray_GeometrySrcType;
635    geoSrc.fVertexLayout = vertexLayout;
636    geoSrc.fVertexCount = vertexCount;
637    this->onSetVertexSourceToArray(vertexArray, vertexCount);
638}
639
640void GrDrawTarget::setIndexSourceToArray(const void* indexArray,
641                                         int indexCount) {
642    this->releasePreviousIndexSource();
643    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
644    geoSrc.fIndexSrc = kArray_GeometrySrcType;
645    geoSrc.fIndexCount = indexCount;
646    this->onSetIndexSourceToArray(indexArray, indexCount);
647}
648
649void GrDrawTarget::setVertexSourceToBuffer(GrVertexLayout vertexLayout,
650                                           const GrVertexBuffer* buffer) {
651    this->releasePreviousVertexSource();
652    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
653    geoSrc.fVertexSrc    = kBuffer_GeometrySrcType;
654    geoSrc.fVertexBuffer = buffer;
655    buffer->ref();
656    geoSrc.fVertexLayout = vertexLayout;
657}
658
659void GrDrawTarget::setIndexSourceToBuffer(const GrIndexBuffer* buffer) {
660    this->releasePreviousIndexSource();
661    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
662    geoSrc.fIndexSrc     = kBuffer_GeometrySrcType;
663    geoSrc.fIndexBuffer  = buffer;
664    buffer->ref();
665}
666
667void GrDrawTarget::resetVertexSource() {
668    this->releasePreviousVertexSource();
669    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
670    geoSrc.fVertexSrc = kNone_GeometrySrcType;
671}
672
673void GrDrawTarget::resetIndexSource() {
674    this->releasePreviousIndexSource();
675    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
676    geoSrc.fIndexSrc = kNone_GeometrySrcType;
677}
678
679void GrDrawTarget::pushGeometrySource() {
680    this->geometrySourceWillPush();
681    GeometrySrcState& newState = fGeoSrcStateStack.push_back();
682    newState.fIndexSrc = kNone_GeometrySrcType;
683    newState.fVertexSrc = kNone_GeometrySrcType;
684#if GR_DEBUG
685    newState.fVertexCount  = ~0;
686    newState.fVertexBuffer = (GrVertexBuffer*)~0;
687    newState.fIndexCount   = ~0;
688    newState.fIndexBuffer = (GrIndexBuffer*)~0;
689#endif
690}
691
692void GrDrawTarget::popGeometrySource() {
693    const GeometrySrcState& geoSrc = this->getGeomSrc();
694    // if popping last element then pops are unbalanced with pushes
695    GrAssert(fGeoSrcStateStack.count() > 1);
696
697    this->geometrySourceWillPop(fGeoSrcStateStack.fromBack(1));
698    this->releasePreviousVertexSource();
699    this->releasePreviousIndexSource();
700    fGeoSrcStateStack.pop_back();
701}
702
703////////////////////////////////////////////////////////////////////////////////
704
705bool GrDrawTarget::checkDraw(GrPrimitiveType type, int startVertex,
706                             int startIndex, int vertexCount,
707                             int indexCount) const {
708#if GR_DEBUG
709    const GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
710    int maxVertex = startVertex + vertexCount;
711    int maxValidVertex;
712    switch (geoSrc.fVertexSrc) {
713        case kNone_GeometrySrcType:
714            GrCrash("Attempting to draw without vertex src.");
715        case kReserved_GeometrySrcType: // fallthrough
716        case kArray_GeometrySrcType:
717            maxValidVertex = geoSrc.fVertexCount;
718            break;
719        case kBuffer_GeometrySrcType:
720            maxValidVertex = geoSrc.fVertexBuffer->sizeInBytes() /
721                             VertexSize(geoSrc.fVertexLayout);
722            break;
723    }
724    if (maxVertex > maxValidVertex) {
725        GrCrash("Drawing outside valid vertex range.");
726    }
727    if (indexCount > 0) {
728        int maxIndex = startIndex + indexCount;
729        int maxValidIndex;
730        switch (geoSrc.fIndexSrc) {
731            case kNone_GeometrySrcType:
732                GrCrash("Attempting to draw indexed geom without index src.");
733            case kReserved_GeometrySrcType: // fallthrough
734            case kArray_GeometrySrcType:
735                maxValidIndex = geoSrc.fIndexCount;
736                break;
737            case kBuffer_GeometrySrcType:
738                maxValidIndex = geoSrc.fIndexBuffer->sizeInBytes() / sizeof(uint16_t);
739                break;
740        }
741        if (maxIndex > maxValidIndex) {
742            GrCrash("Index reads outside valid index range.");
743        }
744    }
745#endif
746    const GrDrawState& drawState = this->getDrawState();
747    if (NULL == drawState.getRenderTarget()) {
748        return false;
749    }
750    if (GrPixelConfigIsUnpremultiplied(drawState.getRenderTarget()->config())) {
751        if (kOne_BlendCoeff != drawState.getSrcBlendCoeff() ||
752            kZero_BlendCoeff != drawState.getDstBlendCoeff()) {
753            return false;
754        }
755    }
756    for (int s = 0; s < GrDrawState::kNumStages; ++s) {
757        // We don't support using unpremultiplied textures with filters (other
758        // than nearest). Alpha-premulling is not distributive WRT to filtering.
759        // We'd have to filter each texel before filtering. We could do this for
760        // our custom filters but we would also have to disable bilerp and do
761        // a custom bilerp in the shader. Until Skia itself supports unpremul
762        // configs there is no pressure to implement this.
763        if (this->isStageEnabled(s) &&
764            GrPixelConfigIsUnpremultiplied(drawState.getTexture(s)->config()) &&
765            GrSamplerState::kNearest_Filter !=
766            drawState.getSampler(s).getFilter()) {
767            return false;
768        }
769    }
770    return true;
771}
772
773void GrDrawTarget::drawIndexed(GrPrimitiveType type, int startVertex,
774                               int startIndex, int vertexCount,
775                               int indexCount) {
776    if (indexCount > 0 &&
777        this->checkDraw(type, startVertex, startIndex,
778                        vertexCount, indexCount)) {
779        this->onDrawIndexed(type, startVertex, startIndex,
780                            vertexCount, indexCount);
781    }
782}
783
784void GrDrawTarget::drawNonIndexed(GrPrimitiveType type,
785                                  int startVertex,
786                                  int vertexCount) {
787    if (vertexCount > 0 &&
788        this->checkDraw(type, startVertex, -1, vertexCount, -1)) {
789        this->onDrawNonIndexed(type, startVertex, vertexCount);
790    }
791}
792
793////////////////////////////////////////////////////////////////////////////////
794
795// Some blend modes allow folding a partial coverage value into the color's
796// alpha channel, while others will blend incorrectly.
797bool GrDrawTarget::canTweakAlphaForCoverage() const {
798    /**
799     * The fractional coverage is f
800     * The src and dst coeffs are Cs and Cd
801     * The dst and src colors are S and D
802     * We want the blend to compute: f*Cs*S + (f*Cd + (1-f))D
803     * By tweaking the source color's alpha we're replacing S with S'=fS. It's
804     * obvious that that first term will always be ok. The second term can be
805     * rearranged as [1-(1-Cd)f]D. By substituing in the various possbilities
806     * for Cd we find that only 1, ISA, and ISC produce the correct depth
807     * coeffecient in terms of S' and D.
808     */
809    GrBlendCoeff dstCoeff = this->getDrawState().getDstBlendCoeff();
810    return kOne_BlendCoeff == dstCoeff ||
811           kISA_BlendCoeff == dstCoeff ||
812           kISC_BlendCoeff == dstCoeff;
813}
814
815
816bool GrDrawTarget::srcAlphaWillBeOne() const {
817    const GrVertexLayout& layout = this->getGeomSrc().fVertexLayout;
818    const GrDrawState& drawState = this->getDrawState();
819
820    // Check if per-vertex or constant color may have partial alpha
821    if ((layout & kColor_VertexLayoutBit) ||
822        0xff != GrColorUnpackA(drawState.getColor())) {
823        return false;
824    }
825    // Check if color filter could introduce an alpha
826    // (TODO: Consider being more aggressive with regards to detecting 0xff
827    // final alpha from color filter).
828    if (SkXfermode::kDst_Mode != drawState.getColorFilterMode()) {
829        return false;
830    }
831    // Check if a color stage could create a partial alpha
832    for (int s = 0; s < drawState.getFirstCoverageStage(); ++s) {
833        if (StageWillBeUsed(s, layout, fCurrDrawState)) {
834            GrAssert(NULL != drawState.getTexture(s));
835            GrPixelConfig config = drawState.getTexture(s)->config();
836            if (!GrPixelConfigIsOpaque(config)) {
837                return false;
838            }
839        }
840    }
841    return true;
842}
843
844GrDrawTarget::BlendOptFlags
845GrDrawTarget::getBlendOpts(bool forceCoverage,
846                           GrBlendCoeff* srcCoeff,
847                           GrBlendCoeff* dstCoeff) const {
848
849    const GrVertexLayout& layout = this->getGeomSrc().fVertexLayout;
850    const GrDrawState& drawState = this->getDrawState();
851
852    GrBlendCoeff bogusSrcCoeff, bogusDstCoeff;
853    if (NULL == srcCoeff) {
854        srcCoeff = &bogusSrcCoeff;
855    }
856    *srcCoeff = drawState.getSrcBlendCoeff();
857
858    if (NULL == dstCoeff) {
859        dstCoeff = &bogusDstCoeff;
860    }
861    *dstCoeff = drawState.getDstBlendCoeff();
862
863    // We don't ever expect source coeffecients to reference the source
864    GrAssert(kSA_BlendCoeff != *srcCoeff &&
865             kISA_BlendCoeff != *srcCoeff &&
866             kSC_BlendCoeff != *srcCoeff &&
867             kISC_BlendCoeff != *srcCoeff);
868    // same for dst
869    GrAssert(kDA_BlendCoeff != *dstCoeff &&
870             kIDA_BlendCoeff != *dstCoeff &&
871             kDC_BlendCoeff != *dstCoeff &&
872             kIDC_BlendCoeff != *dstCoeff);
873
874    if (drawState.isColorWriteDisabled()) {
875        *srcCoeff = kZero_BlendCoeff;
876        *dstCoeff = kOne_BlendCoeff;
877    }
878
879    bool srcAIsOne = this->srcAlphaWillBeOne();
880    bool dstCoeffIsOne = kOne_BlendCoeff == *dstCoeff ||
881                         (kSA_BlendCoeff == *dstCoeff && srcAIsOne);
882    bool dstCoeffIsZero = kZero_BlendCoeff == *dstCoeff ||
883                         (kISA_BlendCoeff == *dstCoeff && srcAIsOne);
884
885
886    // When coeffs are (0,1) there is no reason to draw at all, unless
887    // stenciling is enabled. Having color writes disabled is effectively
888    // (0,1).
889    if ((kZero_BlendCoeff == *srcCoeff && dstCoeffIsOne)) {
890        if (drawState.getStencil().doesWrite()) {
891            return kDisableBlend_BlendOptFlag |
892                   kEmitTransBlack_BlendOptFlag;
893        } else {
894            return kSkipDraw_BlendOptFlag;
895        }
896    }
897
898    // check for coverage due to edge aa or coverage texture stage
899    bool hasCoverage = forceCoverage ||
900                       drawState.getNumAAEdges() > 0 ||
901                       (layout & kCoverage_VertexLayoutBit) ||
902                       (layout & kEdge_VertexLayoutBit);
903    for (int s = drawState.getFirstCoverageStage();
904         !hasCoverage && s < GrDrawState::kNumStages;
905         ++s) {
906        if (StageWillBeUsed(s, layout, fCurrDrawState)) {
907            hasCoverage = true;
908        }
909    }
910
911    // if we don't have coverage we can check whether the dst
912    // has to read at all. If not, we'll disable blending.
913    if (!hasCoverage) {
914        if (dstCoeffIsZero) {
915            if (kOne_BlendCoeff == *srcCoeff) {
916                // if there is no coverage and coeffs are (1,0) then we
917                // won't need to read the dst at all, it gets replaced by src
918                return kDisableBlend_BlendOptFlag;
919            } else if (kZero_BlendCoeff == *srcCoeff) {
920                // if the op is "clear" then we don't need to emit a color
921                // or blend, just write transparent black into the dst.
922                *srcCoeff = kOne_BlendCoeff;
923                *dstCoeff = kZero_BlendCoeff;
924                return kDisableBlend_BlendOptFlag |
925                       kEmitTransBlack_BlendOptFlag;
926            }
927        }
928    } else {
929        // check whether coverage can be safely rolled into alpha
930        // of if we can skip color computation and just emit coverage
931        if (this->canTweakAlphaForCoverage()) {
932            return kCoverageAsAlpha_BlendOptFlag;
933        }
934        if (dstCoeffIsZero) {
935            if (kZero_BlendCoeff == *srcCoeff) {
936                // the source color is not included in the blend
937                // the dst coeff is effectively zero so blend works out to:
938                // (c)(0)D + (1-c)D = (1-c)D.
939                *dstCoeff = kISA_BlendCoeff;
940                return  kEmitCoverage_BlendOptFlag;
941            } else if (srcAIsOne) {
942                // the dst coeff is effectively zero so blend works out to:
943                // cS + (c)(0)D + (1-c)D = cS + (1-c)D.
944                // If Sa is 1 then we can replace Sa with c
945                // and set dst coeff to 1-Sa.
946                *dstCoeff = kISA_BlendCoeff;
947                return  kCoverageAsAlpha_BlendOptFlag;
948            }
949        } else if (dstCoeffIsOne) {
950            // the dst coeff is effectively one so blend works out to:
951            // cS + (c)(1)D + (1-c)D = cS + D.
952            *dstCoeff = kOne_BlendCoeff;
953            return  kCoverageAsAlpha_BlendOptFlag;
954        }
955    }
956    return kNone_BlendOpt;
957}
958
959bool GrDrawTarget::willUseHWAALines() const {
960    // there is a conflict between using smooth lines and our use of
961    // premultiplied alpha. Smooth lines tweak the incoming alpha value
962    // but not in a premul-alpha way. So we only use them when our alpha
963    // is 0xff and tweaking the color for partial coverage is OK
964    if (!fCaps.fHWAALineSupport ||
965        !this->getDrawState().isHWAntialiasState()) {
966        return false;
967    }
968    BlendOptFlags opts = this->getBlendOpts();
969    return (kDisableBlend_BlendOptFlag & opts) &&
970           (kCoverageAsAlpha_BlendOptFlag & opts);
971}
972
973bool GrDrawTarget::canApplyCoverage() const {
974    // we can correctly apply coverage if a) we have dual source blending
975    // or b) one of our blend optimizations applies.
976    return this->getCaps().fDualSourceBlendingSupport ||
977           kNone_BlendOpt != this->getBlendOpts(true);
978}
979
980bool GrDrawTarget::drawWillReadDst() const {
981    return SkToBool((kDisableBlend_BlendOptFlag | kSkipDraw_BlendOptFlag) &
982                    this->getBlendOpts());
983}
984
985
986////////////////////////////////////////////////////////////////////////////////
987
988void GrDrawTarget::drawRect(const GrRect& rect,
989                            const GrMatrix* matrix,
990                            StageMask stageMask,
991                            const GrRect* srcRects[],
992                            const GrMatrix* srcMatrices[]) {
993    GrVertexLayout layout = GetRectVertexLayout(stageMask, srcRects);
994
995    AutoReleaseGeometry geo(this, layout, 4, 0);
996    if (!geo.succeeded()) {
997        GrPrintf("Failed to get space for vertices!\n");
998        return;
999    }
1000
1001    SetRectVertices(rect, matrix, srcRects,
1002                    srcMatrices, layout, geo.vertices());
1003
1004    drawNonIndexed(kTriangleFan_PrimitiveType, 0, 4);
1005}
1006
1007GrVertexLayout GrDrawTarget::GetRectVertexLayout(StageMask stageMask,
1008                                                 const GrRect* srcRects[]) {
1009    GrVertexLayout layout = 0;
1010
1011    for (int i = 0; i < GrDrawState::kNumStages; ++i) {
1012        int numTC = 0;
1013        if (stageMask & (1 << i)) {
1014            if (NULL != srcRects && NULL != srcRects[i]) {
1015                layout |= StageTexCoordVertexLayoutBit(i, numTC);
1016                ++numTC;
1017            } else {
1018                layout |= StagePosAsTexCoordVertexLayoutBit(i);
1019            }
1020        }
1021    }
1022    return layout;
1023}
1024
1025void GrDrawTarget::clipWillBeSet(const GrClip& clip) {
1026}
1027
1028void GrDrawTarget::SetRectVertices(const GrRect& rect,
1029                                   const GrMatrix* matrix,
1030                                   const GrRect* srcRects[],
1031                                   const GrMatrix* srcMatrices[],
1032                                   GrVertexLayout layout,
1033                                   void* vertices) {
1034#if GR_DEBUG
1035    // check that the layout and srcRects agree
1036    for (int i = 0; i < GrDrawState::kNumStages; ++i) {
1037        if (VertexTexCoordsForStage(i, layout) >= 0) {
1038            GR_DEBUGASSERT(NULL != srcRects && NULL != srcRects[i]);
1039        } else {
1040            GR_DEBUGASSERT(NULL == srcRects || NULL == srcRects[i]);
1041        }
1042    }
1043#endif
1044
1045    int stageOffsets[GrDrawState::kNumStages];
1046    int vsize = VertexSizeAndOffsetsByStage(layout, stageOffsets,
1047                                            NULL, NULL, NULL);
1048
1049    GrTCast<GrPoint*>(vertices)->setRectFan(rect.fLeft, rect.fTop,
1050                                            rect.fRight, rect.fBottom,
1051                                            vsize);
1052    if (NULL != matrix) {
1053        matrix->mapPointsWithStride(GrTCast<GrPoint*>(vertices), vsize, 4);
1054    }
1055
1056    for (int i = 0; i < GrDrawState::kNumStages; ++i) {
1057        if (stageOffsets[i] > 0) {
1058            GrPoint* coords = GrTCast<GrPoint*>(GrTCast<intptr_t>(vertices) +
1059                                                stageOffsets[i]);
1060            coords->setRectFan(srcRects[i]->fLeft, srcRects[i]->fTop,
1061                               srcRects[i]->fRight, srcRects[i]->fBottom,
1062                               vsize);
1063            if (NULL != srcMatrices && NULL != srcMatrices[i]) {
1064                srcMatrices[i]->mapPointsWithStride(coords, vsize, 4);
1065            }
1066        }
1067    }
1068}
1069
1070////////////////////////////////////////////////////////////////////////////////
1071
1072GrDrawTarget::AutoStateRestore::AutoStateRestore() {
1073    fDrawTarget = NULL;
1074}
1075
1076GrDrawTarget::AutoStateRestore::AutoStateRestore(GrDrawTarget* target) {
1077    fDrawTarget = target;
1078    if (NULL != fDrawTarget) {
1079        fDrawTarget->saveCurrentDrawState(&fDrawState);
1080    }
1081}
1082
1083GrDrawTarget::AutoStateRestore::~AutoStateRestore() {
1084    if (NULL != fDrawTarget) {
1085        fDrawTarget->restoreDrawState(fDrawState);
1086    }
1087}
1088
1089void GrDrawTarget::AutoStateRestore::set(GrDrawTarget* target) {
1090    if (target != fDrawTarget) {
1091        if (NULL != fDrawTarget) {
1092            fDrawTarget->restoreDrawState(fDrawState);
1093        }
1094        if (NULL != target) {
1095            target->saveCurrentDrawState(&fDrawState);
1096        }
1097        fDrawTarget = target;
1098    }
1099}
1100
1101////////////////////////////////////////////////////////////////////////////////
1102
1103GrDrawTarget::AutoDeviceCoordDraw::AutoDeviceCoordDraw(
1104                                            GrDrawTarget* target,
1105                                            GrDrawState::StageMask stageMask) {
1106    GrAssert(NULL != target);
1107    GrDrawState* drawState = target->drawState();
1108
1109    fDrawTarget = target;
1110    fViewMatrix = drawState->getViewMatrix();
1111    fStageMask = stageMask;
1112    if (fStageMask) {
1113        GrMatrix invVM;
1114        if (fViewMatrix.invert(&invVM)) {
1115            for (int s = 0; s < GrDrawState::kNumStages; ++s) {
1116                if (fStageMask & (1 << s)) {
1117                    fSamplerMatrices[s] = drawState->getSampler(s).getMatrix();
1118                }
1119            }
1120            drawState->preConcatSamplerMatrices(fStageMask, invVM);
1121        } else {
1122            // sad trombone sound
1123            fStageMask = 0;
1124        }
1125    }
1126    drawState->setViewMatrix(GrMatrix::I());
1127}
1128
1129GrDrawTarget::AutoDeviceCoordDraw::~AutoDeviceCoordDraw() {
1130    GrDrawState* drawState = fDrawTarget->drawState();
1131    drawState->setViewMatrix(fViewMatrix);
1132    for (int s = 0; s < GrDrawState::kNumStages; ++s) {
1133        if (fStageMask & (1 << s)) {
1134            *drawState->sampler(s)->matrix() = fSamplerMatrices[s];
1135        }
1136    }
1137}
1138
1139////////////////////////////////////////////////////////////////////////////////
1140
1141GrDrawTarget::AutoReleaseGeometry::AutoReleaseGeometry(
1142                                         GrDrawTarget*  target,
1143                                         GrVertexLayout vertexLayout,
1144                                         int vertexCount,
1145                                         int indexCount) {
1146    fTarget = NULL;
1147    this->set(target, vertexLayout, vertexCount, indexCount);
1148}
1149
1150GrDrawTarget::AutoReleaseGeometry::AutoReleaseGeometry() {
1151    fTarget = NULL;
1152}
1153
1154GrDrawTarget::AutoReleaseGeometry::~AutoReleaseGeometry() {
1155    this->reset();
1156}
1157
1158bool GrDrawTarget::AutoReleaseGeometry::set(GrDrawTarget*  target,
1159                                            GrVertexLayout vertexLayout,
1160                                            int vertexCount,
1161                                            int indexCount) {
1162    this->reset();
1163    fTarget = target;
1164    bool success = true;
1165    if (NULL != fTarget) {
1166        fTarget = target;
1167        if (vertexCount > 0) {
1168            success = target->reserveVertexSpace(vertexLayout,
1169                                                 vertexCount,
1170                                                 &fVertices);
1171            if (!success) {
1172                this->reset();
1173            }
1174        }
1175        if (success && indexCount > 0) {
1176            success = target->reserveIndexSpace(indexCount, &fIndices);
1177            if (!success) {
1178                this->reset();
1179            }
1180        }
1181    }
1182    GrAssert(success == (NULL != fTarget));
1183    return success;
1184}
1185
1186void GrDrawTarget::AutoReleaseGeometry::reset() {
1187    if (NULL != fTarget) {
1188        if (NULL != fVertices) {
1189            fTarget->resetVertexSource();
1190        }
1191        if (NULL != fIndices) {
1192            fTarget->resetIndexSource();
1193        }
1194        fTarget = NULL;
1195    }
1196    fVertices = NULL;
1197    fIndices = NULL;
1198}
1199
1200void GrDrawTarget::Caps::print() const {
1201    static const char* gNY[] = {"NO", "YES"};
1202    GrPrintf("8 Bit Palette Support       : %s\n", gNY[f8BitPaletteSupport]);
1203    GrPrintf("NPOT Texture Tile Support   : %s\n", gNY[fNPOTTextureTileSupport]);
1204    GrPrintf("Two Sided Stencil Support   : %s\n", gNY[fTwoSidedStencilSupport]);
1205    GrPrintf("Stencil Wrap Ops  Support   : %s\n", gNY[fStencilWrapOpsSupport]);
1206    GrPrintf("HW AA Lines Support         : %s\n", gNY[fHWAALineSupport]);
1207    GrPrintf("Shader Derivative Support   : %s\n", gNY[fShaderDerivativeSupport]);
1208    GrPrintf("Geometry Shader Support     : %s\n", gNY[fGeometryShaderSupport]);
1209    GrPrintf("FSAA Support                : %s\n", gNY[fFSAASupport]);
1210    GrPrintf("Dual Source Blending Support: %s\n", gNY[fDualSourceBlendingSupport]);
1211    GrPrintf("Buffer Lock Support         : %s\n", gNY[fBufferLockSupport]);
1212    GrPrintf("Max Texture Size            : %d\n", fMaxTextureSize);
1213    GrPrintf("Max Render Target Size      : %d\n", fMaxRenderTargetSize);
1214}
1215
1216