Factor out GrAtlasTextBatch fromt GrAtlasTextContext

src/gpu/batches/GrAtlasTextBatch.cpp

+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "GrAtlasTextBatch.h"
+
+#include "GrBatchFontCache.h"
+#include "GrBatchFlushState.h"
+#include "GrBatchTest.h"
+#include "GrResourceProvider.h"
+
+#include "SkDistanceFieldGen.h"
+#include "SkGlyphCache.h"
+
+#include "effects/GrBitmapTextGeoProc.h"
+#include "effects/GrDistanceFieldGeoProc.h"
+
+static inline GrColor skcolor_to_grcolor_nopremultiply(SkColor c) {
+    unsigned r = SkColorGetR(c);
+    unsigned g = SkColorGetG(c);
+    unsigned b = SkColorGetB(c);
+    return GrColorPackRGBA(r, g, b, 0xff);
+}
+
+static const int kDistanceAdjustLumShift = 5;
+
+SkString GrAtlasTextBatch::dumpInfo() const {
+    SkString str;
+
+    for (int i = 0; i < fGeoCount; ++i) {
+        str.appendf("%d: Color: 0x%08x Trans: %.2f,%.2f Runs: %d\n",
+                    i,
+                    fGeoData[i].fColor,
+                    fGeoData[i].fTransX,
+                    fGeoData[i].fTransY,
+                    fGeoData[i].fBlob->fRunCount);
+    }
+
+    str.append(INHERITED::dumpInfo());
+    return str;
+}
+
+void GrAtlasTextBatch::getInvariantOutputColor(GrInitInvariantOutput* out) const {
+    if (kColorBitmapMask_MaskType == fMaskType) {
+        out->setUnknownFourComponents();
+    } else {
+        out->setKnownFourComponents(fBatch.fColor);
+    }
+}
+
+void GrAtlasTextBatch::getInvariantOutputCoverage(GrInitInvariantOutput* out) const {
+    switch (fMaskType) {
+        case kGrayscaleDistanceField_MaskType:
+        case kGrayscaleCoverageMask_MaskType:
+            out->setUnknownSingleComponent();
+            break;
+        case kLCDCoverageMask_MaskType:
+        case kLCDDistanceField_MaskType:
+            out->setUnknownOpaqueFourComponents();
+            out->setUsingLCDCoverage();
+            break;
+        case kColorBitmapMask_MaskType:
+            out->setKnownSingleComponent(0xff);
+    }
+}
+
+void GrAtlasTextBatch::initBatchTracker(const GrPipelineOptimizations& opt) {
+    // Handle any color overrides
+    if (!opt.readsColor()) {
+        fGeoData[0].fColor = GrColor_ILLEGAL;
+    }
+    opt.getOverrideColorIfSet(&fGeoData[0].fColor);
+
+    // setup batch properties
+    fBatch.fColorIgnored = !opt.readsColor();
+    fBatch.fColor = fGeoData[0].fColor;
+    fBatch.fUsesLocalCoords = opt.readsLocalCoords();
+    fBatch.fCoverageIgnored = !opt.readsCoverage();
+}
+
+void GrAtlasTextBatch::onPrepareDraws(Target* target) {
+    // if we have RGB, then we won't have any SkShaders so no need to use a localmatrix.
+    // TODO actually only invert if we don't have RGBA
+    SkMatrix localMatrix;
+    if (this->usesLocalCoords() && !this->viewMatrix().invert(&localMatrix)) {
+        SkDebugf("Cannot invert viewmatrix\n");
+        return;
+    }
+
+    GrTexture* texture = fFontCache->getTexture(this->maskFormat());
+    if (!texture) {
+        SkDebugf("Could not allocate backing texture for atlas\n");
+        return;
+    }
+
+    bool usesDistanceFields = this->usesDistanceFields();
+    GrMaskFormat maskFormat = this->maskFormat();
+    bool isLCD = this->isLCD();
+
+    SkAutoTUnref<const GrGeometryProcessor> gp;
+    if (usesDistanceFields) {
+        gp.reset(this->setupDfProcessor(this->viewMatrix(), fFilteredColor, this->color(),
+                                        texture));
+    } else {
+        GrTextureParams params(SkShader::kClamp_TileMode, GrTextureParams::kNone_FilterMode);
+        gp.reset(GrBitmapTextGeoProc::Create(this->color(),
+                                             texture,
+                                             params,
+                                             maskFormat,
+                                             localMatrix,
+                                             this->usesLocalCoords()));
+    }
+
+    FlushInfo flushInfo;
+    flushInfo.fGlyphsToFlush = 0;
+    size_t vertexStride = gp->getVertexStride();
+    SkASSERT(vertexStride == (usesDistanceFields ?
+                              GetVertexStrideDf(maskFormat, isLCD) :
+                              GetVertexStride(maskFormat)));
+
+    target->initDraw(gp, this->pipeline());
+
+    int glyphCount = this->numGlyphs();
+    const GrVertexBuffer* vertexBuffer;
+
+    void* vertices = target->makeVertexSpace(vertexStride,
+                                             glyphCount * kVerticesPerGlyph,
+                                             &vertexBuffer,
+                                             &flushInfo.fVertexOffset);
+    flushInfo.fVertexBuffer.reset(SkRef(vertexBuffer));
+    flushInfo.fIndexBuffer.reset(target->resourceProvider()->refQuadIndexBuffer());
+    if (!vertices || !flushInfo.fVertexBuffer) {
+        SkDebugf("Could not allocate vertices\n");
+        return;
+    }
+
+    unsigned char* currVertex = reinterpret_cast<unsigned char*>(vertices);
+
+    // We cache some values to avoid going to the glyphcache for the same fontScaler twice
+    // in a row
+    const SkDescriptor* desc = nullptr;
+    SkGlyphCache* cache = nullptr;
+    GrFontScaler* scaler = nullptr;
+    SkTypeface* typeface = nullptr;
+
+    for (int i = 0; i < fGeoCount; i++) {
+        Geometry& args = fGeoData[i];
+        Blob* blob = args.fBlob;
+        Run& run = blob->fRuns[args.fRun];
+        TextInfo& info = run.fSubRunInfo[args.fSubRun];
+
+        uint64_t currentAtlasGen = fFontCache->atlasGeneration(maskFormat);
+        bool regenerateTextureCoords = info.fAtlasGeneration != currentAtlasGen ||
+                                       info.fStrike->isAbandoned();
+        bool regenerateColors;
+        if (usesDistanceFields) {
+            regenerateColors = !isLCD && run.fColor != args.fColor;
+        } else {
+            regenerateColors = kA8_GrMaskFormat == maskFormat && run.fColor != args.fColor;
+        }
+        bool regeneratePositions = args.fTransX != 0.f || args.fTransY != 0.f;
+        int glyphCount = info.fGlyphEndIndex - info.fGlyphStartIndex;
+
+        // We regenerate both texture coords and colors in the blob itself, and update the
+        // atlas generation.  If we don't end up purging any unused plots, we can avoid
+        // regenerating the coords.  We could take a finer grained approach to updating texture
+        // coords but its not clear if the extra bookkeeping would offset any gains.
+        // To avoid looping over the glyphs twice, we do one loop and conditionally update color
+        // or coords as needed.  One final note, if we have to break a run for an atlas eviction
+        // then we can't really trust the atlas has all of the correct data.  Atlas evictions
+        // should be pretty rare, so we just always regenerate in those cases
+        if (regenerateTextureCoords || regenerateColors || regeneratePositions) {
+            // first regenerate texture coordinates / colors if need be
+            bool brokenRun = false;
+
+            // Because the GrBatchFontCache may evict the strike a blob depends on using for
+            // generating its texture coords, we have to track whether or not the strike has
+            // been abandoned.  If it hasn't been abandoned, then we can use the GrGlyph*s as is
+            // otherwise we have to get the new strike, and use that to get the correct glyphs.
+            // Because we do not have the packed ids, and thus can't look up our glyphs in the
+            // new strike, we instead keep our ref to the old strike and use the packed ids from
+            // it.  These ids will still be valid as long as we hold the ref.  When we are done
+            // updating our cache of the GrGlyph*s, we drop our ref on the old strike
+            bool regenerateGlyphs = false;
+            GrBatchTextStrike* strike = nullptr;
+            if (regenerateTextureCoords) {
+                info.fBulkUseToken.reset();
+
+                // We can reuse if we have a valid strike and our descriptors / typeface are the
+                // same.  The override descriptor is only for the non distance field text within
+                // a run
+                const SkDescriptor* newDesc = (run.fOverrideDescriptor && !usesDistanceFields) ?
+                                              run.fOverrideDescriptor->getDesc() :
+                                              run.fDescriptor.getDesc();
+                if (!cache || !SkTypeface::Equal(typeface, run.fTypeface) ||
+                              !(desc->equals(*newDesc))) {
+                    if (cache) {
+                        SkGlyphCache::AttachCache(cache);
+                    }
+                    desc = newDesc;
+                    cache = SkGlyphCache::DetachCache(run.fTypeface, desc);
+                    scaler = GrTextContext::GetGrFontScaler(cache);
+                    strike = info.fStrike;
+                    typeface = run.fTypeface;
+                }
+
+                if (info.fStrike->isAbandoned()) {
+                    regenerateGlyphs = true;
+                    strike = fFontCache->getStrike(scaler);
+                } else {
+                    strike = info.fStrike;
+                }
+            }
+
+            for (int glyphIdx = 0; glyphIdx < glyphCount; glyphIdx++) {
+                if (regenerateTextureCoords) {
+                    size_t glyphOffset = glyphIdx + info.fGlyphStartIndex;
+
+                    GrGlyph* glyph = blob->fGlyphs[glyphOffset];
+                    GrGlyph::PackedID id = glyph->fPackedID;
+                    const SkGlyph& skGlyph = scaler->grToSkGlyph(id);
+                    if (regenerateGlyphs) {
+                        // Get the id from the old glyph, and use the new strike to lookup
+                        // the glyph.
+                        blob->fGlyphs[glyphOffset] = strike->getGlyph(skGlyph, id, maskFormat,
+                                                                      scaler);
+                    }
+                    glyph = blob->fGlyphs[glyphOffset];
+                    SkASSERT(glyph);
+                    SkASSERT(id == glyph->fPackedID);
+                    // We want to be able to assert this but cannot for testing purposes.
+                    // once skbug:4143 has landed we can revist this assert
+                    //SkASSERT(glyph->fMaskFormat == this->maskFormat());
+
+                    if (!fFontCache->hasGlyph(glyph) &&
+                        !strike->addGlyphToAtlas(target, glyph, scaler, skGlyph, maskFormat)) {
+                        this->flush(target, &flushInfo);
+                        target->initDraw(gp, this->pipeline());
+                        brokenRun = glyphIdx > 0;
+
+                        SkDEBUGCODE(bool success =) strike->addGlyphToAtlas(target,
+                                                                            glyph,
+                                                                            scaler,
+                                                                            skGlyph,
+                                                                            maskFormat);
+                        SkASSERT(success);
+                    }
+                    fFontCache->addGlyphToBulkAndSetUseToken(&info.fBulkUseToken, glyph,
+                                                             target->currentToken());
+
+                    // Texture coords are the last vertex attribute so we get a pointer to the
+                    // first one and then map with stride in regenerateTextureCoords
+                    intptr_t vertex = reinterpret_cast<intptr_t>(blob->fVertices);
+                    vertex += info.fVertexStartIndex;
+                    vertex += vertexStride * glyphIdx * kVerticesPerGlyph;
+                    vertex += vertexStride - sizeof(SkIPoint16);
+
+                    this->regenerateTextureCoords(glyph, vertex, vertexStride);
+                }
+
+                if (regenerateColors) {
+                    intptr_t vertex = reinterpret_cast<intptr_t>(blob->fVertices);
+                    vertex += info.fVertexStartIndex;
+                    vertex += vertexStride * glyphIdx * kVerticesPerGlyph + sizeof(SkPoint);
+                    this->regenerateColors(vertex, vertexStride, args.fColor);
+                }
+
+                if (regeneratePositions) {
+                    intptr_t vertex = reinterpret_cast<intptr_t>(blob->fVertices);
+                    vertex += info.fVertexStartIndex;
+                    vertex += vertexStride * glyphIdx * kVerticesPerGlyph;
+                    SkScalar transX = args.fTransX;
+                    SkScalar transY = args.fTransY;
+                    this->regeneratePositions(vertex, vertexStride, transX, transY);
+                }
+                flushInfo.fGlyphsToFlush++;
+            }
+
+            // We my have changed the color so update it here
+            run.fColor = args.fColor;
+            if (regenerateTextureCoords) {
+                if (regenerateGlyphs) {
+                    info.fStrike.reset(SkRef(strike));
+                }
+                info.fAtlasGeneration = brokenRun ? GrBatchAtlas::kInvalidAtlasGeneration :
+                                                    fFontCache->atlasGeneration(maskFormat);
+            }
+        } else {
+            flushInfo.fGlyphsToFlush += glyphCount;
+
+            // set use tokens for all of the glyphs in our subrun.  This is only valid if we
+            // have a valid atlas generation
+            fFontCache->setUseTokenBulk(info.fBulkUseToken, target->currentToken(), maskFormat);
+        }
+
+        // now copy all vertices
+        size_t byteCount = info.fVertexEndIndex - info.fVertexStartIndex;
+        memcpy(currVertex, blob->fVertices + info.fVertexStartIndex, byteCount);
+
+        currVertex += byteCount;
+    }
+    // Make sure to attach the last cache if applicable
+    if (cache) {
+        SkGlyphCache::AttachCache(cache);
+    }
+    this->flush(target, &flushInfo);
+}
+
+void GrAtlasTextBatch::regenerateTextureCoords(GrGlyph* glyph, intptr_t vertex,
+                                               size_t vertexStride) {
+    int width = glyph->fBounds.width();
+    int height = glyph->fBounds.height();
+
+    int u0, v0, u1, v1;
+    if (this->usesDistanceFields()) {
+        u0 = glyph->fAtlasLocation.fX + SK_DistanceFieldInset;
+        v0 = glyph->fAtlasLocation.fY + SK_DistanceFieldInset;
+        u1 = u0 + width - 2 * SK_DistanceFieldInset;
+        v1 = v0 + height - 2 * SK_DistanceFieldInset;
+    } else {
+        u0 = glyph->fAtlasLocation.fX;
+        v0 = glyph->fAtlasLocation.fY;
+        u1 = u0 + width;
+        v1 = v0 + height;
+    }
+
+    SkIPoint16* textureCoords;
+    // V0
+    textureCoords = reinterpret_cast<SkIPoint16*>(vertex);
+    textureCoords->set(u0, v0);
+    vertex += vertexStride;
+
+    // V1
+    textureCoords = reinterpret_cast<SkIPoint16*>(vertex);
+    textureCoords->set(u0, v1);
+    vertex += vertexStride;
+
+    // V2
+    textureCoords = reinterpret_cast<SkIPoint16*>(vertex);
+    textureCoords->set(u1, v1);
+    vertex += vertexStride;
+
+    // V3
+    textureCoords = reinterpret_cast<SkIPoint16*>(vertex);
+    textureCoords->set(u1, v0);
+}
+
+void GrAtlasTextBatch::regenerateColors(intptr_t vertex, size_t vertexStride, GrColor color) {
+    for (int i = 0; i < kVerticesPerGlyph; i++) {
+        SkColor* vcolor = reinterpret_cast<SkColor*>(vertex);
+        *vcolor = color;
+        vertex += vertexStride;
+    }
+}
+
+void GrAtlasTextBatch::regeneratePositions(intptr_t vertex, size_t vertexStride, SkScalar transX,
+                                           SkScalar transY) {
+    for (int i = 0; i < kVerticesPerGlyph; i++) {
+        SkPoint* point = reinterpret_cast<SkPoint*>(vertex);
+        point->fX += transX;
+        point->fY += transY;
+        vertex += vertexStride;
+    }
+}
+
+void GrAtlasTextBatch::flush(GrVertexBatch::Target* target, FlushInfo* flushInfo) {
+    GrVertices vertices;
+    int maxGlyphsPerDraw = flushInfo->fIndexBuffer->maxQuads();
+    vertices.initInstanced(kTriangles_GrPrimitiveType, flushInfo->fVertexBuffer,
+                           flushInfo->fIndexBuffer, flushInfo->fVertexOffset,
+                           kVerticesPerGlyph, kIndicesPerGlyph, flushInfo->fGlyphsToFlush,
+                           maxGlyphsPerDraw);
+    target->draw(vertices);
+    flushInfo->fVertexOffset += kVerticesPerGlyph * flushInfo->fGlyphsToFlush;
+    flushInfo->fGlyphsToFlush = 0;
+}
+
+bool GrAtlasTextBatch::onCombineIfPossible(GrBatch* t, const GrCaps& caps) {
+    GrAtlasTextBatch* that = t->cast<GrAtlasTextBatch>();
+    if (!GrPipeline::CanCombine(*this->pipeline(), this->bounds(), *that->pipeline(),
+                                that->bounds(), caps)) {
+        return false;
+    }
+
+    if (fMaskType != that->fMaskType) {
+        return false;
+    }
+
+    if (!this->usesDistanceFields()) {
+        // TODO we can often batch across LCD text if we have dual source blending and don't
+        // have to use the blend constant
+        if (kGrayscaleCoverageMask_MaskType != fMaskType && this->color() != that->color()) {
+            return false;
+        }
+        if (this->usesLocalCoords() && !this->viewMatrix().cheapEqualTo(that->viewMatrix())) {
+            return false;
+        }
+    } else {
+        if (!this->viewMatrix().cheapEqualTo(that->viewMatrix())) {
+            return false;
+        }
+
+        if (fFilteredColor != that->fFilteredColor) {
+            return false;
+        }
+
+        if (fUseBGR != that->fUseBGR) {
+            return false;
+        }
+
+        // TODO see note above
+        if (kLCDDistanceField_MaskType == fMaskType && this->color() != that->color()) {
+            return false;
+        }
+    }
+
+    fBatch.fNumGlyphs += that->numGlyphs();
+
+    // Reallocate space for geo data if necessary and then import that's geo data.
+    int newGeoCount = that->fGeoCount + fGeoCount;
+    // We assume (and here enforce) that the allocation size is the smallest power of two that
+    // is greater than or equal to the number of geometries (and at least
+    // kMinGeometryAllocated).
+    int newAllocSize = GrNextPow2(newGeoCount);
+    int currAllocSize = SkTMax<int>(kMinGeometryAllocated, GrNextPow2(fGeoCount));
+
+    if (newGeoCount > currAllocSize) {
+        fGeoData.realloc(newAllocSize);
+    }
+
+    memcpy(&fGeoData[fGeoCount], that->fGeoData.get(), that->fGeoCount * sizeof(Geometry));
+    // We steal the ref on the blobs from the other TextBatch and set its count to 0 so that
+    // it doesn't try to unref them.
+#ifdef SK_DEBUG
+    for (int i = 0; i < that->fGeoCount; ++i) {
+        that->fGeoData.get()[i].fBlob = (Blob*)0x1;
+    }
+#endif
+    that->fGeoCount = 0;
+    fGeoCount = newGeoCount;
+
+    this->joinBounds(that->bounds());
+    return true;
+}
+
+// TODO just use class params
+// TODO trying to figure out why lcd is so whack
+GrGeometryProcessor* GrAtlasTextBatch::setupDfProcessor(const SkMatrix& viewMatrix,
+                                                        SkColor filteredColor,
+                                                        GrColor color, GrTexture* texture) {
+    GrTextureParams params(SkShader::kClamp_TileMode, GrTextureParams::kBilerp_FilterMode);
+    bool isLCD = this->isLCD();
+    // set up any flags
+    uint32_t flags = viewMatrix.isSimilarity() ? kSimilarity_DistanceFieldEffectFlag : 0;
+
+    // see if we need to create a new effect
+    if (isLCD) {
+        flags |= kUseLCD_DistanceFieldEffectFlag;
+        flags |= viewMatrix.rectStaysRect() ? kRectToRect_DistanceFieldEffectFlag : 0;
+        flags |= fUseBGR ? kBGR_DistanceFieldEffectFlag : 0;
+
+        GrColor colorNoPreMul = skcolor_to_grcolor_nopremultiply(filteredColor);
+
+        float redCorrection =
+            (*fDistanceAdjustTable)[GrColorUnpackR(colorNoPreMul) >> kDistanceAdjustLumShift];
+        float greenCorrection =
+            (*fDistanceAdjustTable)[GrColorUnpackG(colorNoPreMul) >> kDistanceAdjustLumShift];
+        float blueCorrection =
+            (*fDistanceAdjustTable)[GrColorUnpackB(colorNoPreMul) >> kDistanceAdjustLumShift];
+        GrDistanceFieldLCDTextGeoProc::DistanceAdjust widthAdjust =
+            GrDistanceFieldLCDTextGeoProc::DistanceAdjust::Make(redCorrection,
+                                                                greenCorrection,
+                                                                blueCorrection);
+
+        return GrDistanceFieldLCDTextGeoProc::Create(color,
+                                                     viewMatrix,
+                                                     texture,
+                                                     params,
+                                                     widthAdjust,
+                                                     flags,
+                                                     this->usesLocalCoords());
+    } else {
+        flags |= kColorAttr_DistanceFieldEffectFlag;
+#ifdef SK_GAMMA_APPLY_TO_A8
+        U8CPU lum = SkColorSpaceLuminance::computeLuminance(SK_GAMMA_EXPONENT, filteredColor);
+        float correction = (*fDistanceAdjustTable)[lum >> kDistanceAdjustLumShift];
+        return GrDistanceFieldA8TextGeoProc::Create(color,
+                                                    viewMatrix,
+                                                    texture,
+                                                    params,
+                                                    correction,
+                                                    flags,
+                                                    this->usesLocalCoords());
+#else
+        return GrDistanceFieldA8TextGeoProc::Create(color,
+                                                    viewMatrix,
+                                                    texture,
+                                                    params,
+                                                    flags,
+                                                    this->usesLocalCoords());
+#endif
+    }
+
+}