GrDrawTarget.cpp revision a72eef322c686954cdffa849dc26d8133b802f1d 
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 function 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    0x1111,
79    0x2222,
80    0x4444,
81    0x8888,
82};
83GR_STATIC_ASSERT(GrDrawState::kNumStages == GR_ARRAY_COUNT(gStageTexCoordMasks));
84
85const GrVertexLayout gStageMasks[] = {
86    0x11111,
87    0x22222,
88    0x44444,
89    0x88888,
90};
91GR_STATIC_ASSERT(GrDrawState::kNumStages == GR_ARRAY_COUNT(gStageMasks));
92
93const GrVertexLayout gTexCoordMasks[] = {
94    0xf,
95    0xf0,
96    0xf00,
97    0xf000,
98};
99GR_STATIC_ASSERT(GrDrawState::kMaxTexCoords == GR_ARRAY_COUNT(gTexCoordMasks));
100
101
102bool check_layout(GrVertexLayout layout) {
103    // can only have 1 or 0 bits set for each stage.
104    for (int s = 0; s < GrDrawState::kNumStages; ++s) {
105        int stageBits = layout & gStageMasks[s];
106        if (stageBits && !GrIsPow2(stageBits)) {
107            return false;
108        }
109    }
110    return true;
111}
112
113int num_tex_coords(GrVertexLayout layout) {
114    int cnt = 0;
115    // figure out how many tex coordinates are present
116    for (int t = 0; t < GrDrawState::kMaxTexCoords; ++t) {
117        if (gTexCoordMasks[t] & layout) {
118            ++cnt;
119        }
120    }
121    return cnt;
122}
123
124} //unnamed namespace
125
126size_t GrDrawTarget::VertexSize(GrVertexLayout vertexLayout) {
127    GrAssert(check_layout(vertexLayout));
128
129    size_t vecSize = (vertexLayout & kTextFormat_VertexLayoutBit) ?
130                        sizeof(GrGpuTextVertex) :
131                        sizeof(GrPoint);
132
133    size_t size = vecSize; // position
134    size += num_tex_coords(vertexLayout) * vecSize;
135    if (vertexLayout & kColor_VertexLayoutBit) {
136        size += sizeof(GrColor);
137    }
138    if (vertexLayout & kCoverage_VertexLayoutBit) {
139        size += sizeof(GrColor);
140    }
141    if (vertexLayout & kEdge_VertexLayoutBit) {
142        size += 4 * sizeof(GrScalar);
143    }
144    return size;
145}
146
147////////////////////////////////////////////////////////////////////////////////
148
149/**
150 * Functions for computing offsets of various components from the layout
151 * bitfield.
152 *
153 * Order of vertex components:
154 * Position
155 * Tex Coord 0
156 * ...
157 * Tex Coord GrDrawState::kMaxTexCoords-1
158 * Color
159 * Coverage
160 */
161
162int GrDrawTarget::VertexStageCoordOffset(int stage, GrVertexLayout vertexLayout) {
163    GrAssert(check_layout(vertexLayout));
164    if (StagePosAsTexCoordVertexLayoutBit(stage) & vertexLayout) {
165        return 0;
166    }
167    int tcIdx = VertexTexCoordsForStage(stage, vertexLayout);
168    if (tcIdx >= 0) {
169
170        int vecSize = (vertexLayout & kTextFormat_VertexLayoutBit) ?
171                                    sizeof(GrGpuTextVertex) :
172                                    sizeof(GrPoint);
173        int offset = vecSize; // position
174        // figure out how many tex coordinates are present and precede this one.
175        for (int t = 0; t < tcIdx; ++t) {
176            if (gTexCoordMasks[t] & vertexLayout) {
177                offset += vecSize;
178            }
179        }
180        return offset;
181    }
182
183    return -1;
184}
185
186int GrDrawTarget::VertexColorOffset(GrVertexLayout vertexLayout) {
187    GrAssert(check_layout(vertexLayout));
188
189    if (vertexLayout & kColor_VertexLayoutBit) {
190        int vecSize = (vertexLayout & kTextFormat_VertexLayoutBit) ?
191                                    sizeof(GrGpuTextVertex) :
192                                    sizeof(GrPoint);
193        return vecSize * (num_tex_coords(vertexLayout) + 1); //+1 for pos
194    }
195    return -1;
196}
197
198int GrDrawTarget::VertexCoverageOffset(GrVertexLayout vertexLayout) {
199    GrAssert(check_layout(vertexLayout));
200
201    if (vertexLayout & kCoverage_VertexLayoutBit) {
202        int vecSize = (vertexLayout & kTextFormat_VertexLayoutBit) ?
203                                    sizeof(GrGpuTextVertex) :
204                                    sizeof(GrPoint);
205
206        int offset = vecSize * (num_tex_coords(vertexLayout) + 1);
207        if (vertexLayout & kColor_VertexLayoutBit) {
208            offset += sizeof(GrColor);
209        }
210        return offset;
211    }
212    return -1;
213}
214
215int GrDrawTarget::VertexEdgeOffset(GrVertexLayout vertexLayout) {
216    GrAssert(check_layout(vertexLayout));
217
218    // edge pts are after the pos, tex coords, and color
219    if (vertexLayout & kEdge_VertexLayoutBit) {
220        int vecSize = (vertexLayout & kTextFormat_VertexLayoutBit) ?
221                                    sizeof(GrGpuTextVertex) :
222                                    sizeof(GrPoint);
223        int offset = vecSize * (num_tex_coords(vertexLayout) + 1); //+1 for pos
224        if (vertexLayout & kColor_VertexLayoutBit) {
225            offset += sizeof(GrColor);
226        }
227        if (vertexLayout & kCoverage_VertexLayoutBit) {
228            offset += sizeof(GrColor);
229        }
230        return offset;
231    }
232    return -1;
233}
234
235int GrDrawTarget::VertexSizeAndOffsetsByIdx(
236        GrVertexLayout vertexLayout,
237        int texCoordOffsetsByIdx[GrDrawState::kMaxTexCoords],
238        int* colorOffset,
239        int* coverageOffset,
240        int* edgeOffset) {
241    GrAssert(check_layout(vertexLayout));
242
243    int vecSize = (vertexLayout & kTextFormat_VertexLayoutBit) ?
244                                                    sizeof(GrGpuTextVertex) :
245                                                    sizeof(GrPoint);
246    int size = vecSize; // position
247
248    for (int t = 0; t < GrDrawState::kMaxTexCoords; ++t) {
249        if (gTexCoordMasks[t] & vertexLayout) {
250            if (NULL != texCoordOffsetsByIdx) {
251                texCoordOffsetsByIdx[t] = size;
252            }
253            size += vecSize;
254        } else {
255            if (NULL != texCoordOffsetsByIdx) {
256                texCoordOffsetsByIdx[t] = -1;
257            }
258        }
259    }
260    if (kColor_VertexLayoutBit & vertexLayout) {
261        if (NULL != colorOffset) {
262            *colorOffset = size;
263        }
264        size += sizeof(GrColor);
265    } else {
266        if (NULL != colorOffset) {
267            *colorOffset = -1;
268        }
269    }
270    if (kCoverage_VertexLayoutBit & vertexLayout) {
271        if (NULL != coverageOffset) {
272            *coverageOffset = size;
273        }
274        size += sizeof(GrColor);
275    } else {
276        if (NULL != coverageOffset) {
277            *coverageOffset = -1;
278        }
279    }
280    if (kEdge_VertexLayoutBit & vertexLayout) {
281        if (NULL != edgeOffset) {
282            *edgeOffset = size;
283        }
284        size += 4 * sizeof(GrScalar);
285    } else {
286        if (NULL != edgeOffset) {
287            *edgeOffset = -1;
288        }
289    }
290    return size;
291}
292
293int GrDrawTarget::VertexSizeAndOffsetsByStage(
294        GrVertexLayout vertexLayout,
295        int texCoordOffsetsByStage[GrDrawState::kNumStages],
296        int* colorOffset,
297        int* coverageOffset,
298        int* edgeOffset) {
299    GrAssert(check_layout(vertexLayout));
300
301    int texCoordOffsetsByIdx[GrDrawState::kMaxTexCoords];
302    int size = VertexSizeAndOffsetsByIdx(vertexLayout,
303                                         (NULL == texCoordOffsetsByStage) ?
304                                               NULL :
305                                               texCoordOffsetsByIdx,
306                                         colorOffset,
307                                         coverageOffset,
308                                         edgeOffset);
309    if (NULL != texCoordOffsetsByStage) {
310        for (int s = 0; s < GrDrawState::kNumStages; ++s) {
311            int tcIdx;
312            if (StagePosAsTexCoordVertexLayoutBit(s) & vertexLayout) {
313                texCoordOffsetsByStage[s] = 0;
314            } else if ((tcIdx = VertexTexCoordsForStage(s, vertexLayout)) >= 0) {
315                texCoordOffsetsByStage[s] = texCoordOffsetsByIdx[tcIdx];
316            } else {
317                texCoordOffsetsByStage[s] = -1;
318            }
319        }
320    }
321    return size;
322}
323
324////////////////////////////////////////////////////////////////////////////////
325
326bool GrDrawTarget::VertexUsesStage(int stage, GrVertexLayout vertexLayout) {
327    GrAssert(stage < GrDrawState::kNumStages);
328    GrAssert(check_layout(vertexLayout));
329    return !!(gStageMasks[stage] & vertexLayout);
330}
331
332bool GrDrawTarget::VertexUsesTexCoordIdx(int coordIndex,
333                                         GrVertexLayout vertexLayout) {
334    GrAssert(coordIndex < GrDrawState::kMaxTexCoords);
335    GrAssert(check_layout(vertexLayout));
336    return !!(gTexCoordMasks[coordIndex] & vertexLayout);
337}
338
339int GrDrawTarget::VertexTexCoordsForStage(int stage,
340                                          GrVertexLayout vertexLayout) {
341    GrAssert(stage < GrDrawState::kNumStages);
342    GrAssert(check_layout(vertexLayout));
343    int bit = vertexLayout & gStageTexCoordMasks[stage];
344    if (bit) {
345        // figure out which set of texture coordates is used
346        // bits are ordered T0S0, T0S1, T0S2, ..., T1S0, T1S1, ...
347        // and start at bit 0.
348        GR_STATIC_ASSERT(sizeof(GrVertexLayout) <= sizeof(uint32_t));
349        return (32 - Gr_clz(bit) - 1) / GrDrawState::kNumStages;
350    }
351    return -1;
352}
353
354////////////////////////////////////////////////////////////////////////////////
355
356void GrDrawTarget::VertexLayoutUnitTest() {
357    // Ensure that our globals mask arrays are correct
358    GrVertexLayout stageTexCoordMasks[GrDrawState::kNumStages];
359    GrVertexLayout stageMasks[GrDrawState::kNumStages];
360    GrVertexLayout texCoordMasks[GrDrawState::kMaxTexCoords];
361    gen_mask_arrays(stageTexCoordMasks, stageMasks, texCoordMasks);
362    for (int s = 0; s < GrDrawState::kNumStages; ++s) {
363        GrAssert(stageTexCoordMasks[s] == gStageTexCoordMasks[s]);
364        GrAssert(stageMasks[s] == gStageMasks[s]);
365    }
366    for (int t = 0; t < GrDrawState::kMaxTexCoords; ++t) {
367        GrAssert(texCoordMasks[t] == gTexCoordMasks[t]);
368    }
369
370    // not necessarily exhaustive
371    static bool run;
372    if (!run) {
373        run = true;
374        for (int s = 0; s < GrDrawState::kNumStages; ++s) {
375
376            GrAssert(!VertexUsesStage(s, 0));
377            GrAssert(-1 == VertexStageCoordOffset(s, 0));
378            GrVertexLayout stageMask = 0;
379            for (int t = 0; t < GrDrawState::kMaxTexCoords; ++t) {
380                stageMask |= StageTexCoordVertexLayoutBit(s,t);
381            }
382            GrAssert(1 == GrDrawState::kMaxTexCoords ||
383                     !check_layout(stageMask));
384            GrAssert(gStageTexCoordMasks[s] == stageMask);
385            stageMask |= StagePosAsTexCoordVertexLayoutBit(s);
386            GrAssert(gStageMasks[s] == stageMask);
387            GrAssert(!check_layout(stageMask));
388        }
389        for (int t = 0; t < GrDrawState::kMaxTexCoords; ++t) {
390            GrVertexLayout tcMask = 0;
391            GrAssert(!VertexUsesTexCoordIdx(t, 0));
392            for (int s = 0; s < GrDrawState::kNumStages; ++s) {
393                tcMask |= StageTexCoordVertexLayoutBit(s,t);
394                GrAssert(VertexUsesStage(s, tcMask));
395                GrAssert(sizeof(GrPoint) == VertexStageCoordOffset(s, tcMask));
396                GrAssert(VertexUsesTexCoordIdx(t, tcMask));
397                GrAssert(2*sizeof(GrPoint) == VertexSize(tcMask));
398                GrAssert(t == VertexTexCoordsForStage(s, tcMask));
399                for (int s2 = s + 1; s2 < GrDrawState::kNumStages; ++s2) {
400                    GrAssert(-1 == VertexStageCoordOffset(s2, tcMask));
401                    GrAssert(!VertexUsesStage(s2, tcMask));
402                    GrAssert(-1 == VertexTexCoordsForStage(s2, tcMask));
403
404                #if GR_DEBUG
405                    GrVertexLayout posAsTex = tcMask | StagePosAsTexCoordVertexLayoutBit(s2);
406                #endif
407                    GrAssert(0 == VertexStageCoordOffset(s2, posAsTex));
408                    GrAssert(VertexUsesStage(s2, posAsTex));
409                    GrAssert(2*sizeof(GrPoint) == VertexSize(posAsTex));
410                    GrAssert(-1 == VertexTexCoordsForStage(s2, posAsTex));
411                    GrAssert(-1 == VertexEdgeOffset(posAsTex));
412                }
413                GrAssert(-1 == VertexEdgeOffset(tcMask));
414                GrAssert(-1 == VertexColorOffset(tcMask));
415                GrAssert(-1 == VertexCoverageOffset(tcMask));
416            #if GR_DEBUG
417                GrVertexLayout withColor = tcMask | kColor_VertexLayoutBit;
418            #endif
419                GrAssert(-1 == VertexCoverageOffset(withColor));
420                GrAssert(2*sizeof(GrPoint) == VertexColorOffset(withColor));
421                GrAssert(2*sizeof(GrPoint) + sizeof(GrColor) == VertexSize(withColor));
422            #if GR_DEBUG
423                GrVertexLayout withEdge = tcMask | kEdge_VertexLayoutBit;
424            #endif
425                GrAssert(-1 == VertexColorOffset(withEdge));
426                GrAssert(2*sizeof(GrPoint) == VertexEdgeOffset(withEdge));
427                GrAssert(4*sizeof(GrPoint) == VertexSize(withEdge));
428            #if GR_DEBUG
429                GrVertexLayout withColorAndEdge = withColor | kEdge_VertexLayoutBit;
430            #endif
431                GrAssert(2*sizeof(GrPoint) == VertexColorOffset(withColorAndEdge));
432                GrAssert(2*sizeof(GrPoint) + sizeof(GrColor) == VertexEdgeOffset(withColorAndEdge));
433                GrAssert(4*sizeof(GrPoint) + sizeof(GrColor) == VertexSize(withColorAndEdge));
434            #if GR_DEBUG
435                GrVertexLayout withCoverage = tcMask | kCoverage_VertexLayoutBit;
436            #endif
437                GrAssert(-1 == VertexColorOffset(withCoverage));
438                GrAssert(2*sizeof(GrPoint) == VertexCoverageOffset(withCoverage));
439                GrAssert(2*sizeof(GrPoint) + sizeof(GrColor) == VertexSize(withCoverage));
440            #if GR_DEBUG
441                GrVertexLayout withCoverageAndColor = tcMask | kCoverage_VertexLayoutBit |
442                                                      kColor_VertexLayoutBit;
443            #endif
444                GrAssert(2*sizeof(GrPoint) == VertexColorOffset(withCoverageAndColor));
445                GrAssert(2*sizeof(GrPoint) + sizeof(GrColor) == VertexCoverageOffset(withCoverageAndColor));
446                GrAssert(2*sizeof(GrPoint) + 2 * sizeof(GrColor) == VertexSize(withCoverageAndColor));
447            }
448            GrAssert(gTexCoordMasks[t] == tcMask);
449            GrAssert(check_layout(tcMask));
450
451            int stageOffsets[GrDrawState::kNumStages];
452            int colorOffset;
453            int edgeOffset;
454            int coverageOffset;
455            int size;
456            size = VertexSizeAndOffsetsByStage(tcMask,
457                                               stageOffsets, &colorOffset,
458                                               &coverageOffset, &edgeOffset);
459            GrAssert(2*sizeof(GrPoint) == size);
460            GrAssert(-1 == colorOffset);
461            GrAssert(-1 == coverageOffset);
462            GrAssert(-1 == edgeOffset);
463            for (int s = 0; s < GrDrawState::kNumStages; ++s) {
464                GrAssert(VertexUsesStage(s, tcMask));
465                GrAssert(sizeof(GrPoint) == stageOffsets[s]);
466                GrAssert(sizeof(GrPoint) == VertexStageCoordOffset(s, tcMask));
467            }
468        }
469    }
470}
471
472////////////////////////////////////////////////////////////////////////////////
473
474#define DEBUG_INVAL_BUFFER 0xdeadcafe
475#define DEBUG_INVAL_START_IDX -1
476
477GrDrawTarget::GrDrawTarget() {
478#if GR_DEBUG
479    VertexLayoutUnitTest();
480#endif
481    fDrawState = &fDefaultDrawState;
482    // We assume that fDrawState always owns a ref to the object it points at.
483    fDefaultDrawState.ref();
484    GeometrySrcState& geoSrc = fGeoSrcStateStack.push_back();
485#if GR_DEBUG
486    geoSrc.fVertexCount = DEBUG_INVAL_START_IDX;
487    geoSrc.fVertexBuffer = (GrVertexBuffer*)DEBUG_INVAL_BUFFER;
488    geoSrc.fIndexCount = DEBUG_INVAL_START_IDX;
489    geoSrc.fIndexBuffer = (GrIndexBuffer*)DEBUG_INVAL_BUFFER;
490#endif
491    geoSrc.fVertexSrc = kNone_GeometrySrcType;
492    geoSrc.fIndexSrc  = kNone_GeometrySrcType;
493}
494
495GrDrawTarget::~GrDrawTarget() {
496    GrAssert(1 == fGeoSrcStateStack.count());
497    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
498    GrAssert(kNone_GeometrySrcType == geoSrc.fIndexSrc);
499    GrAssert(kNone_GeometrySrcType == geoSrc.fVertexSrc);
500    fDrawState->unref();
501}
502
503void GrDrawTarget::releaseGeometry() {
504    int popCnt = fGeoSrcStateStack.count() - 1;
505    while (popCnt) {
506        this->popGeometrySource();
507        --popCnt;
508    }
509    this->resetVertexSource();
510    this->resetIndexSource();
511}
512
513void GrDrawTarget::setClip(const GrClip& clip) {
514    clipWillBeSet(clip);
515    fClip = clip;
516}
517
518const GrClip& GrDrawTarget::getClip() const {
519    return fClip;
520}
521
522void GrDrawTarget::setDrawState(GrDrawState*  drawState) {
523    GrAssert(NULL != fDrawState);
524    if (NULL == drawState) {
525        drawState = &fDefaultDrawState;
526    }
527    if (fDrawState != drawState) {
528        fDrawState->unref();
529        drawState->ref();
530        fDrawState = drawState;
531    }
532}
533
534bool GrDrawTarget::reserveVertexSpace(GrVertexLayout vertexLayout,
535                                      int vertexCount,
536                                      void** vertices) {
537    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
538    bool acquired = false;
539    if (vertexCount > 0) {
540        GrAssert(NULL != vertices);
541        this->releasePreviousVertexSource();
542        geoSrc.fVertexSrc = kNone_GeometrySrcType;
543
544        acquired = this->onReserveVertexSpace(vertexLayout,
545                                              vertexCount,
546                                              vertices);
547    }
548    if (acquired) {
549        geoSrc.fVertexSrc = kReserved_GeometrySrcType;
550        geoSrc.fVertexCount = vertexCount;
551        geoSrc.fVertexLayout = vertexLayout;
552    } else if (NULL != vertices) {
553        *vertices = NULL;
554    }
555    return acquired;
556}
557
558bool GrDrawTarget::reserveIndexSpace(int indexCount,
559                                     void** indices) {
560    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
561    bool acquired = false;
562    if (indexCount > 0) {
563        GrAssert(NULL != indices);
564        this->releasePreviousIndexSource();
565        geoSrc.fIndexSrc = kNone_GeometrySrcType;
566
567        acquired = this->onReserveIndexSpace(indexCount, indices);
568    }
569    if (acquired) {
570        geoSrc.fIndexSrc = kReserved_GeometrySrcType;
571        geoSrc.fIndexCount = indexCount;
572    } else if (NULL != indices) {
573        *indices = NULL;
574    }
575    return acquired;
576
577}
578
579bool GrDrawTarget::reserveVertexAndIndexSpace(GrVertexLayout vertexLayout,
580                                              int vertexCount,
581                                              int indexCount,
582                                              void** vertices,
583                                              void** indices) {
584    this->willReserveVertexAndIndexSpace(vertexLayout, vertexCount, indexCount);
585    if (vertexCount) {
586        if (!this->reserveVertexSpace(vertexLayout, vertexCount, vertices)) {
587            if (indexCount) {
588                this->resetIndexSource();
589            }
590            return false;
591        }
592    }
593    if (indexCount) {
594        if (!this->reserveIndexSpace(indexCount, indices)) {
595            if (vertexCount) {
596                this->resetVertexSource();
597            }
598            return false;
599        }
600    }
601    return true;
602}
603
604bool GrDrawTarget::geometryHints(GrVertexLayout vertexLayout,
605                                 int32_t* vertexCount,
606                                 int32_t* indexCount) const {
607    if (NULL != vertexCount) {
608        *vertexCount = -1;
609    }
610    if (NULL != indexCount) {
611        *indexCount = -1;
612    }
613    return false;
614}
615
616void GrDrawTarget::releasePreviousVertexSource() {
617    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
618    switch (geoSrc.fVertexSrc) {
619        case kNone_GeometrySrcType:
620            break;
621        case kArray_GeometrySrcType:
622            this->releaseVertexArray();
623            break;
624        case kReserved_GeometrySrcType:
625            this->releaseReservedVertexSpace();
626            break;
627        case kBuffer_GeometrySrcType:
628            geoSrc.fVertexBuffer->unref();
629#if GR_DEBUG
630            geoSrc.fVertexBuffer = (GrVertexBuffer*)DEBUG_INVAL_BUFFER;
631#endif
632            break;
633        default:
634            GrCrash("Unknown Vertex Source Type.");
635            break;
636    }
637}
638
639void GrDrawTarget::releasePreviousIndexSource() {
640    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
641    switch (geoSrc.fIndexSrc) {
642        case kNone_GeometrySrcType:   // these two don't require
643            break;
644        case kArray_GeometrySrcType:
645            this->releaseIndexArray();
646            break;
647        case kReserved_GeometrySrcType:
648            this->releaseReservedIndexSpace();
649            break;
650        case kBuffer_GeometrySrcType:
651            geoSrc.fIndexBuffer->unref();
652#if GR_DEBUG
653            geoSrc.fIndexBuffer = (GrIndexBuffer*)DEBUG_INVAL_BUFFER;
654#endif
655            break;
656        default:
657            GrCrash("Unknown Index Source Type.");
658            break;
659    }
660}
661
662void GrDrawTarget::setVertexSourceToArray(GrVertexLayout vertexLayout,
663                                          const void* vertexArray,
664                                          int vertexCount) {
665    this->releasePreviousVertexSource();
666    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
667    geoSrc.fVertexSrc = kArray_GeometrySrcType;
668    geoSrc.fVertexLayout = vertexLayout;
669    geoSrc.fVertexCount = vertexCount;
670    this->onSetVertexSourceToArray(vertexArray, vertexCount);
671}
672
673void GrDrawTarget::setIndexSourceToArray(const void* indexArray,
674                                         int indexCount) {
675    this->releasePreviousIndexSource();
676    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
677    geoSrc.fIndexSrc = kArray_GeometrySrcType;
678    geoSrc.fIndexCount = indexCount;
679    this->onSetIndexSourceToArray(indexArray, indexCount);
680}
681
682void GrDrawTarget::setVertexSourceToBuffer(GrVertexLayout vertexLayout,
683                                           const GrVertexBuffer* buffer) {
684    this->releasePreviousVertexSource();
685    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
686    geoSrc.fVertexSrc    = kBuffer_GeometrySrcType;
687    geoSrc.fVertexBuffer = buffer;
688    buffer->ref();
689    geoSrc.fVertexLayout = vertexLayout;
690}
691
692void GrDrawTarget::setIndexSourceToBuffer(const GrIndexBuffer* buffer) {
693    this->releasePreviousIndexSource();
694    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
695    geoSrc.fIndexSrc     = kBuffer_GeometrySrcType;
696    geoSrc.fIndexBuffer  = buffer;
697    buffer->ref();
698}
699
700void GrDrawTarget::resetVertexSource() {
701    this->releasePreviousVertexSource();
702    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
703    geoSrc.fVertexSrc = kNone_GeometrySrcType;
704}
705
706void GrDrawTarget::resetIndexSource() {
707    this->releasePreviousIndexSource();
708    GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
709    geoSrc.fIndexSrc = kNone_GeometrySrcType;
710}
711
712void GrDrawTarget::pushGeometrySource() {
713    this->geometrySourceWillPush();
714    GeometrySrcState& newState = fGeoSrcStateStack.push_back();
715    newState.fIndexSrc = kNone_GeometrySrcType;
716    newState.fVertexSrc = kNone_GeometrySrcType;
717#if GR_DEBUG
718    newState.fVertexCount  = ~0;
719    newState.fVertexBuffer = (GrVertexBuffer*)~0;
720    newState.fIndexCount   = ~0;
721    newState.fIndexBuffer = (GrIndexBuffer*)~0;
722#endif
723}
724
725void GrDrawTarget::popGeometrySource() {
726    const GeometrySrcState& geoSrc = this->getGeomSrc();
727    // if popping last element then pops are unbalanced with pushes
728    GrAssert(fGeoSrcStateStack.count() > 1);
729
730    this->geometrySourceWillPop(fGeoSrcStateStack.fromBack(1));
731    this->releasePreviousVertexSource();
732    this->releasePreviousIndexSource();
733    fGeoSrcStateStack.pop_back();
734}
735
736////////////////////////////////////////////////////////////////////////////////
737
738bool GrDrawTarget::checkDraw(GrPrimitiveType type, int startVertex,
739                             int startIndex, int vertexCount,
740                             int indexCount) const {
741#if GR_DEBUG
742    const GeometrySrcState& geoSrc = fGeoSrcStateStack.back();
743    int maxVertex = startVertex + vertexCount;
744    int maxValidVertex;
745    switch (geoSrc.fVertexSrc) {
746        case kNone_GeometrySrcType:
747            GrCrash("Attempting to draw without vertex src.");
748        case kReserved_GeometrySrcType: // fallthrough
749        case kArray_GeometrySrcType:
750            maxValidVertex = geoSrc.fVertexCount;
751            break;
752        case kBuffer_GeometrySrcType:
753            maxValidVertex = geoSrc.fVertexBuffer->sizeInBytes() /
754                             VertexSize(geoSrc.fVertexLayout);
755            break;
756    }
757    if (maxVertex > maxValidVertex) {
758        GrCrash("Drawing outside valid vertex range.");
759    }
760    if (indexCount > 0) {
761        int maxIndex = startIndex + indexCount;
762        int maxValidIndex;
763        switch (geoSrc.fIndexSrc) {
764            case kNone_GeometrySrcType:
765                GrCrash("Attempting to draw indexed geom without index src.");
766            case kReserved_GeometrySrcType: // fallthrough
767            case kArray_GeometrySrcType:
768                maxValidIndex = geoSrc.fIndexCount;
769                break;
770            case kBuffer_GeometrySrcType:
771                maxValidIndex = geoSrc.fIndexBuffer->sizeInBytes() / sizeof(uint16_t);
772                break;
773        }
774        if (maxIndex > maxValidIndex) {
775            GrCrash("Index reads outside valid index range.");
776        }
777    }
778
779    GrAssert(NULL != this->getDrawState().getRenderTarget());
780    for (int i = 0; i < GrDrawState::kNumStages; ++i) {
781        if (this->getDrawState().getTexture(i)) {
782            GrAssert(this->getDrawState().getTexture(i)->asRenderTarget() !=
783                     this->getDrawState().getRenderTarget());
784        }
785    }
786#endif
787    const GrDrawState& drawState = this->getDrawState();
788    if (NULL == drawState.getRenderTarget()) {
789        return false;
790    }
791    if (GrPixelConfigIsUnpremultiplied(drawState.getRenderTarget()->config())) {
792        if (kOne_BlendCoeff != drawState.getSrcBlendCoeff() ||
793            kZero_BlendCoeff != drawState.getDstBlendCoeff()) {
794            return false;
795        }
796    }
797    for (int s = 0; s < GrDrawState::kNumStages; ++s) {
798        // We don't support using unpremultiplied textures with filters (other
799        // than nearest). Alpha-premulling is not distributive WRT to filtering.
800        // We'd have to filter each texel before filtering. We could do this for
801        // our custom filters but we would also have to disable bilerp and do
802        // a custom bilerp in the shader. Until Skia itself supports unpremul
803        // configs there is no pressure to implement this.
804        if (this->isStageEnabled(s) &&
805            GrPixelConfigIsUnpremultiplied(drawState.getTexture(s)->config()) &&
806            GrSamplerState::kNearest_Filter !=
807            drawState.getSampler(s).getFilter()) {
808            return false;
809        }
810    }
811    return true;
812}
813
814void GrDrawTarget::drawIndexed(GrPrimitiveType type, int startVertex,
815                               int startIndex, int vertexCount,
816                               int indexCount) {
817    if (indexCount > 0 &&
818        this->checkDraw(type, startVertex, startIndex,
819                        vertexCount, indexCount)) {
820        this->onDrawIndexed(type, startVertex, startIndex,
821                            vertexCount, indexCount);
822    }
823}
824
825void GrDrawTarget::drawNonIndexed(GrPrimitiveType type,
826                                  int startVertex,
827                                  int vertexCount) {
828    if (vertexCount > 0 &&
829        this->checkDraw(type, startVertex, -1, vertexCount, -1)) {
830        this->onDrawNonIndexed(type, startVertex, vertexCount);
831    }
832}
833
834////////////////////////////////////////////////////////////////////////////////
835
836// Some blend modes allow folding a partial coverage value into the color's
837// alpha channel, while others will blend incorrectly.
838bool GrDrawTarget::canTweakAlphaForCoverage() const {
839    /**
840     * The fractional coverage is f
841     * The src and dst coeffs are Cs and Cd
842     * The dst and src colors are S and D
843     * We want the blend to compute: f*Cs*S + (f*Cd + (1-f))D
844     * By tweaking the source color's alpha we're replacing S with S'=fS. It's
845     * obvious that that first term will always be ok. The second term can be
846     * rearranged as [1-(1-Cd)f]D. By substituing in the various possbilities
847     * for Cd we find that only 1, ISA, and ISC produce the correct depth
848     * coeffecient in terms of S' and D.
849     */
850    GrBlendCoeff dstCoeff = this->getDrawState().getDstBlendCoeff();
851    return kOne_BlendCoeff == dstCoeff ||
852           kISA_BlendCoeff == dstCoeff ||
853           kISC_BlendCoeff == dstCoeff;
854}
855
856bool GrDrawTarget::srcAlphaWillBeOne(GrVertexLayout layout) const {
857    const GrDrawState& drawState = this->getDrawState();
858
859    // Check if per-vertex or constant color may have partial alpha
860    if ((layout & kColor_VertexLayoutBit) ||
861        0xff != GrColorUnpackA(drawState.getColor())) {
862        return false;
863    }
864    // Check if color filter could introduce an alpha
865    // (TODO: Consider being more aggressive with regards to detecting 0xff
866    // final alpha from color filter).
867    if (SkXfermode::kDst_Mode != drawState.getColorFilterMode()) {
868        return false;
869    }
870    // Check if a color stage could create a partial alpha
871    for (int s = 0; s < drawState.getFirstCoverageStage(); ++s) {
872        if (StageWillBeUsed(s, layout, this->getDrawState())) {
873            GrAssert(NULL != drawState.getTexture(s));
874            GrPixelConfig config = drawState.getTexture(s)->config();
875            if (!GrPixelConfigIsOpaque(config)) {
876                return false;
877            }
878        }
879    }
880    return true;
881}
882
883namespace {
884GrVertexLayout default_blend_opts_vertex_layout() {
885    GrVertexLayout layout = 0;
886    for (int s = 0; s < GrDrawState::kNumStages; ++s) {
887        layout |= GrDrawTarget::StagePosAsTexCoordVertexLayoutBit(s);
888    }
889    return layout;
890}
891}
892
893GrDrawTarget::BlendOptFlags
894GrDrawTarget::getBlendOpts(bool forceCoverage,
895                           GrBlendCoeff* srcCoeff,
896                           GrBlendCoeff* dstCoeff) const {
897
898    GrVertexLayout layout;
899    if (kNone_GeometrySrcType == this->getGeomSrc().fVertexSrc) {
900        layout = default_blend_opts_vertex_layout();
901    } else {
902        layout = this->getVertexLayout();
903    }
904
905    const GrDrawState& drawState = this->getDrawState();
906
907    GrBlendCoeff bogusSrcCoeff, bogusDstCoeff;
908    if (NULL == srcCoeff) {
909        srcCoeff = &bogusSrcCoeff;
910    }
911    *srcCoeff = drawState.getSrcBlendCoeff();
912
913    if (NULL == dstCoeff) {
914        dstCoeff = &bogusDstCoeff;
915    }
916    *dstCoeff = drawState.getDstBlendCoeff();
917
918    // We don't ever expect source coeffecients to reference the source
919    GrAssert(kSA_BlendCoeff != *srcCoeff &&
920             kISA_BlendCoeff != *srcCoeff &&
921             kSC_BlendCoeff != *srcCoeff &&
922             kISC_BlendCoeff != *srcCoeff);
923    // same for dst
924    GrAssert(kDA_BlendCoeff != *dstCoeff &&
925             kIDA_BlendCoeff != *dstCoeff &&
926             kDC_BlendCoeff != *dstCoeff &&
927             kIDC_BlendCoeff != *dstCoeff);
928
929    if (drawState.isColorWriteDisabled()) {
930        *srcCoeff = kZero_BlendCoeff;
931        *dstCoeff = kOne_BlendCoeff;
932    }
933
934    bool srcAIsOne = this->srcAlphaWillBeOne(layout);
935    bool dstCoeffIsOne = kOne_BlendCoeff == *dstCoeff ||
936                         (kSA_BlendCoeff == *dstCoeff && srcAIsOne);
937    bool dstCoeffIsZero = kZero_BlendCoeff == *dstCoeff ||
938                         (kISA_BlendCoeff == *dstCoeff && srcAIsOne);
939
940
941    // When coeffs are (0,1) there is no reason to draw at all, unless
942    // stenciling is enabled. Having color writes disabled is effectively
943    // (0,1). The same applies when coverage is known to be 0.
944    if ((kZero_BlendCoeff == *srcCoeff && dstCoeffIsOne) ||
945        (!(layout & kCoverage_VertexLayoutBit) &&
946         0 == drawState.getCoverage())) {
947        if (drawState.getStencil().doesWrite()) {
948            return kDisableBlend_BlendOptFlag |
949                   kEmitTransBlack_BlendOptFlag;
950        } else {
951            return kSkipDraw_BlendOptFlag;
952        }
953    }
954
955    // check for coverage due to constant coverage, per-vertex coverage,
956    // edge aa or coverage texture stage
957    bool hasCoverage = forceCoverage ||
958                       0xffffffff != drawState.getCoverage() ||
959                       drawState.getNumAAEdges() > 0 ||
960                       (layout & kCoverage_VertexLayoutBit) ||
961                       (layout & kEdge_VertexLayoutBit);
962    for (int s = drawState.getFirstCoverageStage();
963         !hasCoverage && s < GrDrawState::kNumStages;
964         ++s) {
965        if (StageWillBeUsed(s, layout, this->getDrawState())) {
966            hasCoverage = true;
967        }
968    }
969
970    // if we don't have coverage we can check whether the dst
971    // has to read at all. If not, we'll disable blending.
972    if (!hasCoverage) {
973        if (dstCoeffIsZero) {
974            if (kOne_BlendCoeff == *srcCoeff) {
975                // if there is no coverage and coeffs are (1,0) then we
976                // won't need to read the dst at all, it gets replaced by src
977                return kDisableBlend_BlendOptFlag;
978            } else if (kZero_BlendCoeff == *srcCoeff) {
979                // if the op is "clear" then we don't need to emit a color
980                // or blend, just write transparent black into the dst.
981                *srcCoeff = kOne_BlendCoeff;
982                *dstCoeff = kZero_BlendCoeff;
983                return kDisableBlend_BlendOptFlag |
984                       kEmitTransBlack_BlendOptFlag;
985            }
986        }
987    } else {
988        // check whether coverage can be safely rolled into alpha
989        // of if we can skip color computation and just emit coverage
990        if (this->canTweakAlphaForCoverage()) {
991            return kCoverageAsAlpha_BlendOptFlag;
992        }
993        if (dstCoeffIsZero) {
994            if (kZero_BlendCoeff == *srcCoeff) {
995                // the source color is not included in the blend
996                // the dst coeff is effectively zero so blend works out to:
997                // (c)(0)D + (1-c)D = (1-c)D.
998                *dstCoeff = kISA_BlendCoeff;
999                return  kEmitCoverage_BlendOptFlag;
1000            } else if (srcAIsOne) {
1001                // the dst coeff is effectively zero so blend works out to:
1002                // cS + (c)(0)D + (1-c)D = cS + (1-c)D.
1003                // If Sa is 1 then we can replace Sa with c
1004                // and set dst coeff to 1-Sa.
1005                *dstCoeff = kISA_BlendCoeff;
1006                return  kCoverageAsAlpha_BlendOptFlag;
1007            }
1008        } else if (dstCoeffIsOne) {
1009            // the dst coeff is effectively one so blend works out to:
1010            // cS + (c)(1)D + (1-c)D = cS + D.
1011            *dstCoeff = kOne_BlendCoeff;
1012            return  kCoverageAsAlpha_BlendOptFlag;
1013        }
1014    }
1015    return kNone_BlendOpt;
1016}
1017
1018bool GrDrawTarget::willUseHWAALines() const {
1019    // there is a conflict between using smooth lines and our use of
1020    // premultiplied alpha. Smooth lines tweak the incoming alpha value
1021    // but not in a premul-alpha way. So we only use them when our alpha
1022    // is 0xff and tweaking the color for partial coverage is OK
1023    if (!fCaps.fHWAALineSupport ||
1024        !this->getDrawState().isHWAntialiasState()) {
1025        return false;
1026    }
1027    BlendOptFlags opts = this->getBlendOpts();
1028    return (kDisableBlend_BlendOptFlag & opts) &&
1029           (kCoverageAsAlpha_BlendOptFlag & opts);
1030}
1031
1032bool GrDrawTarget::canApplyCoverage() const {
1033    // we can correctly apply coverage if a) we have dual source blending
1034    // or b) one of our blend optimizations applies.
1035    return this->getCaps().fDualSourceBlendingSupport ||
1036           kNone_BlendOpt != this->getBlendOpts(true);
1037}
1038
1039////////////////////////////////////////////////////////////////////////////////
1040
1041void GrDrawTarget::drawIndexedInstances(GrPrimitiveType type,
1042                                        int instanceCount,
1043                                        int verticesPerInstance,
1044                                        int indicesPerInstance) {
1045    if (!verticesPerInstance || !indicesPerInstance) {
1046        return;
1047    }
1048
1049    int instancesPerDraw = this->indexCountInCurrentSource() /
1050                           indicesPerInstance;
1051    if (!instancesPerDraw) {
1052        return;
1053    }
1054
1055    instancesPerDraw = GrMin(instanceCount, instancesPerDraw);
1056    int startVertex = 0;
1057    while (instanceCount) {
1058        this->drawIndexed(type,
1059                          startVertex,
1060                          0,
1061                          verticesPerInstance * instancesPerDraw,
1062                          indicesPerInstance * instancesPerDraw);
1063        startVertex += verticesPerInstance;
1064        instanceCount -= instancesPerDraw;
1065    }
1066}
1067
1068////////////////////////////////////////////////////////////////////////////////
1069
1070void GrDrawTarget::drawRect(const GrRect& rect,
1071                            const GrMatrix* matrix,
1072                            StageMask stageMask,
1073                            const GrRect* srcRects[],
1074                            const GrMatrix* srcMatrices[]) {
1075    GrVertexLayout layout = GetRectVertexLayout(stageMask, srcRects);
1076
1077    AutoReleaseGeometry geo(this, layout, 4, 0);
1078    if (!geo.succeeded()) {
1079        GrPrintf("Failed to get space for vertices!\n");
1080        return;
1081    }
1082
1083    SetRectVertices(rect, matrix, srcRects,
1084                    srcMatrices, layout, geo.vertices());
1085
1086    drawNonIndexed(kTriangleFan_PrimitiveType, 0, 4);
1087}
1088
1089GrVertexLayout GrDrawTarget::GetRectVertexLayout(StageMask stageMask,
1090                                                 const GrRect* srcRects[]) {
1091    GrVertexLayout layout = 0;
1092
1093    for (int i = 0; i < GrDrawState::kNumStages; ++i) {
1094        int numTC = 0;
1095        if (stageMask & (1 << i)) {
1096            if (NULL != srcRects && NULL != srcRects[i]) {
1097                layout |= StageTexCoordVertexLayoutBit(i, numTC);
1098                ++numTC;
1099            } else {
1100                layout |= StagePosAsTexCoordVertexLayoutBit(i);
1101            }
1102        }
1103    }
1104    return layout;
1105}
1106
1107void GrDrawTarget::clipWillBeSet(const GrClip& clip) {
1108}
1109
1110void GrDrawTarget::SetRectVertices(const GrRect& rect,
1111                                   const GrMatrix* matrix,
1112                                   const GrRect* srcRects[],
1113                                   const GrMatrix* srcMatrices[],
1114                                   GrVertexLayout layout,
1115                                   void* vertices) {
1116#if GR_DEBUG
1117    // check that the layout and srcRects agree
1118    for (int i = 0; i < GrDrawState::kNumStages; ++i) {
1119        if (VertexTexCoordsForStage(i, layout) >= 0) {
1120            GR_DEBUGASSERT(NULL != srcRects && NULL != srcRects[i]);
1121        } else {
1122            GR_DEBUGASSERT(NULL == srcRects || NULL == srcRects[i]);
1123        }
1124    }
1125#endif
1126
1127    int stageOffsets[GrDrawState::kNumStages];
1128    int vsize = VertexSizeAndOffsetsByStage(layout, stageOffsets,
1129                                            NULL, NULL, NULL);
1130
1131    GrTCast<GrPoint*>(vertices)->setRectFan(rect.fLeft, rect.fTop,
1132                                            rect.fRight, rect.fBottom,
1133                                            vsize);
1134    if (NULL != matrix) {
1135        matrix->mapPointsWithStride(GrTCast<GrPoint*>(vertices), vsize, 4);
1136    }
1137
1138    for (int i = 0; i < GrDrawState::kNumStages; ++i) {
1139        if (stageOffsets[i] > 0) {
1140            GrPoint* coords = GrTCast<GrPoint*>(GrTCast<intptr_t>(vertices) +
1141                                                stageOffsets[i]);
1142            coords->setRectFan(srcRects[i]->fLeft, srcRects[i]->fTop,
1143                               srcRects[i]->fRight, srcRects[i]->fBottom,
1144                               vsize);
1145            if (NULL != srcMatrices && NULL != srcMatrices[i]) {
1146                srcMatrices[i]->mapPointsWithStride(coords, vsize, 4);
1147            }
1148        }
1149    }
1150}
1151
1152////////////////////////////////////////////////////////////////////////////////
1153
1154GrDrawTarget::AutoStateRestore::AutoStateRestore() {
1155    fDrawTarget = NULL;
1156}
1157
1158GrDrawTarget::AutoStateRestore::AutoStateRestore(GrDrawTarget* target,
1159                                                 ASRInit init) {
1160    fDrawTarget = NULL;
1161    this->set(target, init);
1162}
1163
1164GrDrawTarget::AutoStateRestore::~AutoStateRestore() {
1165    if (NULL != fDrawTarget) {
1166        fDrawTarget->setDrawState(fSavedState);
1167        fSavedState->unref();
1168    }
1169}
1170
1171void GrDrawTarget::AutoStateRestore::set(GrDrawTarget* target, ASRInit init) {
1172    GrAssert(NULL == fDrawTarget);
1173    fDrawTarget = target;
1174    fSavedState = target->drawState();
1175    GrAssert(fSavedState);
1176    fSavedState->ref();
1177    if (kReset_ASRInit == init) {
1178        // calls the default cons
1179        fTempState.init();
1180    } else {
1181        GrAssert(kPreserve_ASRInit == init);
1182        // calls the copy cons
1183        fTempState.set(*fSavedState);
1184    }
1185    target->setDrawState(fTempState.get());
1186}
1187
1188////////////////////////////////////////////////////////////////////////////////
1189
1190GrDrawTarget::AutoDeviceCoordDraw::AutoDeviceCoordDraw(
1191                                            GrDrawTarget* target,
1192                                            GrDrawState::StageMask stageMask) {
1193    GrAssert(NULL != target);
1194    GrDrawState* drawState = target->drawState();
1195
1196    fDrawTarget = target;
1197    fViewMatrix = drawState->getViewMatrix();
1198    fStageMask = stageMask;
1199    if (fStageMask) {
1200        GrMatrix invVM;
1201        if (fViewMatrix.invert(&invVM)) {
1202            for (int s = 0; s < GrDrawState::kNumStages; ++s) {
1203                if (fStageMask & (1 << s)) {
1204                    fSamplerMatrices[s] = drawState->getSampler(s).getMatrix();
1205                }
1206            }
1207            drawState->preConcatSamplerMatrices(fStageMask, invVM);
1208        } else {
1209            // sad trombone sound
1210            fStageMask = 0;
1211        }
1212    }
1213    drawState->viewMatrix()->reset();
1214}
1215
1216GrDrawTarget::AutoDeviceCoordDraw::~AutoDeviceCoordDraw() {
1217    GrDrawState* drawState = fDrawTarget->drawState();
1218    drawState->setViewMatrix(fViewMatrix);
1219    for (int s = 0; s < GrDrawState::kNumStages; ++s) {
1220        if (fStageMask & (1 << s)) {
1221            *drawState->sampler(s)->matrix() = fSamplerMatrices[s];
1222        }
1223    }
1224}
1225
1226////////////////////////////////////////////////////////////////////////////////
1227
1228GrDrawTarget::AutoReleaseGeometry::AutoReleaseGeometry(
1229                                         GrDrawTarget*  target,
1230                                         GrVertexLayout vertexLayout,
1231                                         int vertexCount,
1232                                         int indexCount) {
1233    fTarget = NULL;
1234    this->set(target, vertexLayout, vertexCount, indexCount);
1235}
1236
1237GrDrawTarget::AutoReleaseGeometry::AutoReleaseGeometry() {
1238    fTarget = NULL;
1239}
1240
1241GrDrawTarget::AutoReleaseGeometry::~AutoReleaseGeometry() {
1242    this->reset();
1243}
1244
1245bool GrDrawTarget::AutoReleaseGeometry::set(GrDrawTarget*  target,
1246                                            GrVertexLayout vertexLayout,
1247                                            int vertexCount,
1248                                            int indexCount) {
1249    this->reset();
1250    fTarget = target;
1251    bool success = true;
1252    if (NULL != fTarget) {
1253        fTarget = target;
1254        success = target->reserveVertexAndIndexSpace(vertexLayout,
1255                                                     vertexCount,
1256                                                     indexCount,
1257                                                     &fVertices,
1258                                                     &fIndices);
1259        if (!success) {
1260            fTarget = NULL;
1261            this->reset();
1262        }
1263    }
1264    GrAssert(success == (NULL != fTarget));
1265    return success;
1266}
1267
1268void GrDrawTarget::AutoReleaseGeometry::reset() {
1269    if (NULL != fTarget) {
1270        if (NULL != fVertices) {
1271            fTarget->resetVertexSource();
1272        }
1273        if (NULL != fIndices) {
1274            fTarget->resetIndexSource();
1275        }
1276        fTarget = NULL;
1277    }
1278    fVertices = NULL;
1279    fIndices = NULL;
1280}
1281
1282void GrDrawTarget::Caps::print() const {
1283    static const char* gNY[] = {"NO", "YES"};
1284    GrPrintf("8 Bit Palette Support       : %s\n", gNY[f8BitPaletteSupport]);
1285    GrPrintf("NPOT Texture Tile Support   : %s\n", gNY[fNPOTTextureTileSupport]);
1286    GrPrintf("Two Sided Stencil Support   : %s\n", gNY[fTwoSidedStencilSupport]);
1287    GrPrintf("Stencil Wrap Ops  Support   : %s\n", gNY[fStencilWrapOpsSupport]);
1288    GrPrintf("HW AA Lines Support         : %s\n", gNY[fHWAALineSupport]);
1289    GrPrintf("Shader Derivative Support   : %s\n", gNY[fShaderDerivativeSupport]);
1290    GrPrintf("Geometry Shader Support     : %s\n", gNY[fGeometryShaderSupport]);
1291    GrPrintf("FSAA Support                : %s\n", gNY[fFSAASupport]);
1292    GrPrintf("Dual Source Blending Support: %s\n", gNY[fDualSourceBlendingSupport]);
1293    GrPrintf("Buffer Lock Support         : %s\n", gNY[fBufferLockSupport]);
1294    GrPrintf("Max Texture Size            : %d\n", fMaxTextureSize);
1295    GrPrintf("Max Render Target Size      : %d\n", fMaxRenderTargetSize);
1296}
1297
1298
1299