/*
* 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 "GrAtlasTextContext.h"
#include "GrContext.h"
#include "GrContextPriv.h"
#include "GrTextBlobCache.h"
#include "SkDistanceFieldGen.h"
#include "SkDraw.h"
#include "SkDrawFilter.h"
#include "SkFindAndPlaceGlyph.h"
#include "SkGr.h"
#include "SkGraphics.h"
#include "SkMakeUnique.h"
#include "SkMaskFilterBase.h"
#include "ops/GrMeshDrawOp.h"
// DF sizes and thresholds for usage of the small and medium sizes. For example, above
// kSmallDFFontLimit we will use the medium size. The large size is used up until the size at
// which we switch over to drawing as paths as controlled by Options.
static const int kSmallDFFontSize = 32;
static const int kSmallDFFontLimit = 32;
static const int kMediumDFFontSize = 72;
static const int kMediumDFFontLimit = 72;
static const int kLargeDFFontSize = 162;
static const int kDefaultMinDistanceFieldFontSize = 18;
#ifdef SK_BUILD_FOR_ANDROID
static const int kDefaultMaxDistanceFieldFontSize = 384;
#else
static const int kDefaultMaxDistanceFieldFontSize = 2 * kLargeDFFontSize;
#endif
GrAtlasTextContext::GrAtlasTextContext(const Options& options)
: fDistanceAdjustTable(new GrDistanceFieldAdjustTable) {
fMaxDistanceFieldFontSize = options.fMaxDistanceFieldFontSize < 0.f
? kDefaultMaxDistanceFieldFontSize
: options.fMaxDistanceFieldFontSize;
fMinDistanceFieldFontSize = options.fMinDistanceFieldFontSize < 0.f
? kDefaultMinDistanceFieldFontSize
: options.fMinDistanceFieldFontSize;
fDistanceFieldVerticesAlwaysHaveW = options.fDistanceFieldVerticesAlwaysHaveW;
}
std::unique_ptr<GrAtlasTextContext> GrAtlasTextContext::Make(const Options& options) {
return std::unique_ptr<GrAtlasTextContext>(new GrAtlasTextContext(options));
}
bool GrAtlasTextContext::canDraw(const GrAtlasGlyphCache* fontCache,
const SkPaint& skPaint,
const SkMatrix& viewMatrix,
const SkSurfaceProps& props,
const GrShaderCaps& shaderCaps) {
return this->canDrawAsDistanceFields(skPaint, viewMatrix, props, shaderCaps) ||
!SkDraw::ShouldDrawTextAsPaths(skPaint, viewMatrix, fontCache->getGlyphSizeLimit());
}
SkColor GrAtlasTextContext::ComputeCanonicalColor(const SkPaint& paint, bool lcd) {
SkColor canonicalColor = paint.computeLuminanceColor();
if (lcd) {
// This is the correct computation, but there are tons of cases where LCD can be overridden.
// For now we just regenerate if any run in a textblob has LCD.
// TODO figure out where all of these overrides are and see if we can incorporate that logic
// at a higher level *OR* use sRGB
SkASSERT(false);
//canonicalColor = SkMaskGamma::CanonicalColor(canonicalColor);
} else {
// A8, though can have mixed BMP text but it shouldn't matter because BMP text won't have
// gamma corrected masks anyways, nor color
U8CPU lum = SkComputeLuminance(SkColorGetR(canonicalColor),
SkColorGetG(canonicalColor),
SkColorGetB(canonicalColor));
// reduce to our finite number of bits
canonicalColor = SkMaskGamma::CanonicalColor(SkColorSetRGB(lum, lum, lum));
}
return canonicalColor;
}
SkScalerContextFlags GrAtlasTextContext::ComputeScalerContextFlags(
const GrColorSpaceInfo& colorSpaceInfo) {
// If we're doing gamma-correct rendering, then we can disable the gamma hacks.
// Otherwise, leave them on. In either case, we still want the contrast boost:
if (colorSpaceInfo.isGammaCorrect()) {
return SkScalerContextFlags::kBoostContrast;
} else {
return SkScalerContextFlags::kFakeGammaAndBoostContrast;
}
}
// TODO if this function ever shows up in profiling, then we can compute this value when the
// textblob is being built and cache it. However, for the time being textblobs mostly only have 1
// run so this is not a big deal to compute here.
bool GrAtlasTextContext::HasLCD(const SkTextBlob* blob) {
SkTextBlobRunIterator it(blob);
for (; !it.done(); it.next()) {
if (it.isLCD()) {
return true;
}
}
return false;
}
void GrAtlasTextContext::drawTextBlob(GrContext* context, GrTextUtils::Target* target,
const GrClip& clip, const SkPaint& skPaint,
const SkMatrix& viewMatrix, const SkSurfaceProps& props,
const SkTextBlob* blob, SkScalar x, SkScalar y,
SkDrawFilter* drawFilter, const SkIRect& clipBounds) {
// If we have been abandoned, then don't draw
if (context->abandoned()) {
return;
}
sk_sp<GrAtlasTextBlob> cacheBlob;
SkMaskFilterBase::BlurRec blurRec;
GrAtlasTextBlob::Key key;
// It might be worth caching these things, but its not clear at this time
// TODO for animated mask filters, this will fill up our cache. We need a safeguard here
const SkMaskFilter* mf = skPaint.getMaskFilter();
bool canCache = !(skPaint.getPathEffect() ||
(mf && !as_MFB(mf)->asABlur(&blurRec)) ||
drawFilter);
SkScalerContextFlags scalerContextFlags = ComputeScalerContextFlags(target->colorSpaceInfo());
auto atlasGlyphCache = context->contextPriv().getAtlasGlyphCache();
GrTextBlobCache* textBlobCache = context->contextPriv().getTextBlobCache();
if (canCache) {
bool hasLCD = HasLCD(blob);
// We canonicalize all non-lcd draws to use kUnknown_SkPixelGeometry
SkPixelGeometry pixelGeometry = hasLCD ? props.pixelGeometry() :
kUnknown_SkPixelGeometry;
// TODO we want to figure out a way to be able to use the canonical color on LCD text,
// see the note on ComputeCanonicalColor above. We pick a dummy value for LCD text to
// ensure we always match the same key
GrColor canonicalColor = hasLCD ? SK_ColorTRANSPARENT :
ComputeCanonicalColor(skPaint, hasLCD);
key.fPixelGeometry = pixelGeometry;
key.fUniqueID = blob->uniqueID();
key.fStyle = skPaint.getStyle();
key.fHasBlur = SkToBool(mf);
key.fCanonicalColor = canonicalColor;
key.fScalerContextFlags = scalerContextFlags;
cacheBlob = textBlobCache->find(key);
}
GrTextUtils::Paint paint(&skPaint, &target->colorSpaceInfo());
if (cacheBlob) {
if (cacheBlob->mustRegenerate(paint, blurRec, viewMatrix, x, y)) {
// We have to remake the blob because changes may invalidate our masks.
// TODO we could probably get away reuse most of the time if the pointer is unique,
// but we'd have to clear the subrun information
textBlobCache->remove(cacheBlob.get());
cacheBlob = textBlobCache->makeCachedBlob(blob, key, blurRec, skPaint);
this->regenerateTextBlob(cacheBlob.get(), atlasGlyphCache,
*context->caps()->shaderCaps(), paint, scalerContextFlags,
viewMatrix, props, blob, x, y, drawFilter);
} else {
textBlobCache->makeMRU(cacheBlob.get());
if (CACHE_SANITY_CHECK) {
int glyphCount = 0;
int runCount = 0;
GrTextBlobCache::BlobGlyphCount(&glyphCount, &runCount, blob);
sk_sp<GrAtlasTextBlob> sanityBlob(textBlobCache->makeBlob(glyphCount, runCount));
sanityBlob->setupKey(key, blurRec, skPaint);
this->regenerateTextBlob(sanityBlob.get(), atlasGlyphCache,
*context->caps()->shaderCaps(), paint, scalerContextFlags,
viewMatrix, props, blob, x, y, drawFilter);
GrAtlasTextBlob::AssertEqual(*sanityBlob, *cacheBlob);
}
}
} else {
if (canCache) {
cacheBlob = textBlobCache->makeCachedBlob(blob, key, blurRec, skPaint);
} else {
cacheBlob = textBlobCache->makeBlob(blob);
}
this->regenerateTextBlob(cacheBlob.get(), atlasGlyphCache,
*context->caps()->shaderCaps(), paint, scalerContextFlags,
viewMatrix, props, blob, x, y, drawFilter);
}
cacheBlob->flushCached(atlasGlyphCache, target, blob, props, fDistanceAdjustTable.get(), paint,
drawFilter, clip, viewMatrix, clipBounds, x, y);
}
void GrAtlasTextContext::regenerateTextBlob(GrAtlasTextBlob* cacheBlob,
GrAtlasGlyphCache* fontCache,
const GrShaderCaps& shaderCaps,
const GrTextUtils::Paint& paint,
SkScalerContextFlags scalerContextFlags,
const SkMatrix& viewMatrix,
const SkSurfaceProps& props, const SkTextBlob* blob,
SkScalar x, SkScalar y,
SkDrawFilter* drawFilter) const {
cacheBlob->initReusableBlob(paint.luminanceColor(), viewMatrix, x, y);
// Regenerate textblob
SkTextBlobRunIterator it(blob);
GrTextUtils::RunPaint runPaint(&paint, drawFilter, props);
for (int run = 0; !it.done(); it.next(), run++) {
int glyphCount = it.glyphCount();
size_t textLen = glyphCount * sizeof(uint16_t);
const SkPoint& offset = it.offset();
cacheBlob->push_back_run(run);
if (!runPaint.modifyForRun(it)) {
continue;
}
if (this->canDrawAsDistanceFields(runPaint, viewMatrix, props, shaderCaps)) {
switch (it.positioning()) {
case SkTextBlob::kDefault_Positioning: {
this->drawDFText(cacheBlob, run, fontCache, props, runPaint, scalerContextFlags,
viewMatrix, (const char*)it.glyphs(), textLen, x + offset.x(),
y + offset.y());
break;
}
case SkTextBlob::kHorizontal_Positioning: {
SkPoint dfOffset = SkPoint::Make(x, y + offset.y());
this->drawDFPosText(cacheBlob, run, fontCache, props, runPaint,
scalerContextFlags, viewMatrix, (const char*)it.glyphs(),
textLen, it.pos(), 1, dfOffset);
break;
}
case SkTextBlob::kFull_Positioning: {
SkPoint dfOffset = SkPoint::Make(x, y);
this->drawDFPosText(cacheBlob, run, fontCache, props, runPaint,
scalerContextFlags, viewMatrix, (const char*)it.glyphs(),
textLen, it.pos(), 2, dfOffset);
break;
}
}
} else if (SkDraw::ShouldDrawTextAsPaths(runPaint, viewMatrix)) {
cacheBlob->setRunTooBigForAtlas(run);
} else {
switch (it.positioning()) {
case SkTextBlob::kDefault_Positioning:
DrawBmpText(cacheBlob, run, fontCache, props, runPaint, scalerContextFlags,
viewMatrix, (const char*)it.glyphs(), textLen, x + offset.x(),
y + offset.y());
break;
case SkTextBlob::kHorizontal_Positioning:
DrawBmpPosText(cacheBlob, run, fontCache, props, runPaint, scalerContextFlags,
viewMatrix, (const char*)it.glyphs(), textLen, it.pos(), 1,
SkPoint::Make(x, y + offset.y()), SK_Scalar1);
break;
case SkTextBlob::kFull_Positioning:
DrawBmpPosText(cacheBlob, run, fontCache, props, runPaint, scalerContextFlags,
viewMatrix, (const char*)it.glyphs(), textLen, it.pos(), 2,
SkPoint::Make(x, y), SK_Scalar1);
break;
}
}
}
}
inline sk_sp<GrAtlasTextBlob>
GrAtlasTextContext::makeDrawTextBlob(GrTextBlobCache* blobCache,
GrAtlasGlyphCache* fontCache,
const GrShaderCaps& shaderCaps,
const GrTextUtils::Paint& paint,
SkScalerContextFlags scalerContextFlags,
const SkMatrix& viewMatrix,
const SkSurfaceProps& props,
const char text[], size_t byteLength,
SkScalar x, SkScalar y) const {
int glyphCount = paint.skPaint().countText(text, byteLength);
if (!glyphCount) {
return nullptr;
}
sk_sp<GrAtlasTextBlob> blob = blobCache->makeBlob(glyphCount, 1);
blob->initThrowawayBlob(viewMatrix, x, y);
if (this->canDrawAsDistanceFields(paint, viewMatrix, props, shaderCaps)) {
this->drawDFText(blob.get(), 0, fontCache, props, paint, scalerContextFlags, viewMatrix,
text, byteLength, x, y);
} else {
DrawBmpText(blob.get(), 0, fontCache, props, paint, scalerContextFlags, viewMatrix, text,
byteLength, x, y);
}
return blob;
}
inline sk_sp<GrAtlasTextBlob>
GrAtlasTextContext::makeDrawPosTextBlob(GrTextBlobCache* blobCache,
GrAtlasGlyphCache* fontCache,
const GrShaderCaps& shaderCaps,
const GrTextUtils::Paint& paint,
SkScalerContextFlags scalerContextFlags,
const SkMatrix& viewMatrix,
const SkSurfaceProps& props,
const char text[], size_t byteLength,
const SkScalar pos[], int scalarsPerPosition, const
SkPoint& offset) const {
int glyphCount = paint.skPaint().countText(text, byteLength);
if (!glyphCount) {
return nullptr;
}
sk_sp<GrAtlasTextBlob> blob = blobCache->makeBlob(glyphCount, 1);
blob->initThrowawayBlob(viewMatrix, offset.x(), offset.y());
if (this->canDrawAsDistanceFields(paint, viewMatrix, props, shaderCaps)) {
this->drawDFPosText(blob.get(), 0, fontCache, props, paint, scalerContextFlags, viewMatrix,
text, byteLength, pos, scalarsPerPosition, offset);
} else {
DrawBmpPosText(blob.get(), 0, fontCache, props, paint, scalerContextFlags, viewMatrix, text,
byteLength, pos, scalarsPerPosition, offset, SK_Scalar1);
}
return blob;
}
void GrAtlasTextContext::drawText(GrContext* context, GrTextUtils::Target* target,
const GrClip& clip, const SkPaint& skPaint,
const SkMatrix& viewMatrix, const SkSurfaceProps& props,
const char text[], size_t byteLength, SkScalar x, SkScalar y,
const SkIRect& regionClipBounds) {
if (context->abandoned()) {
return;
}
auto atlasGlyphCache = context->contextPriv().getAtlasGlyphCache();
auto textBlobCache = context->contextPriv().getTextBlobCache();
GrTextUtils::Paint paint(&skPaint, &target->colorSpaceInfo());
if (this->canDraw(atlasGlyphCache, skPaint, viewMatrix, props,
*context->caps()->shaderCaps())) {
sk_sp<GrAtlasTextBlob> blob(
this->makeDrawTextBlob(textBlobCache, atlasGlyphCache,
*context->caps()->shaderCaps(), paint,
ComputeScalerContextFlags(target->colorSpaceInfo()),
viewMatrix, props, text, byteLength, x, y));
if (blob) {
blob->flushThrowaway(atlasGlyphCache, target, props, fDistanceAdjustTable.get(), paint,
clip, viewMatrix, regionClipBounds, x, y);
}
return;
}
// fall back to drawing as a path or scaled glyph
GrTextUtils::DrawBigText(target, clip, paint, viewMatrix, text, byteLength, x, y,
regionClipBounds);
}
void GrAtlasTextContext::drawPosText(GrContext* context, GrTextUtils::Target* target,
const GrClip& clip, const SkPaint& skPaint,
const SkMatrix& viewMatrix, const SkSurfaceProps& props,
const char text[], size_t byteLength, const SkScalar pos[],
int scalarsPerPosition, const SkPoint& offset,
const SkIRect& regionClipBounds) {
GrTextUtils::Paint paint(&skPaint, &target->colorSpaceInfo());
if (context->abandoned()) {
return;
}
auto atlasGlyphCache = context->contextPriv().getAtlasGlyphCache();
auto textBlobCache = context->contextPriv().getTextBlobCache();
if (this->canDraw(atlasGlyphCache, skPaint, viewMatrix, props,
*context->caps()->shaderCaps())) {
sk_sp<GrAtlasTextBlob> blob(this->makeDrawPosTextBlob(
textBlobCache, atlasGlyphCache,
*context->caps()->shaderCaps(), paint,
ComputeScalerContextFlags(target->colorSpaceInfo()), viewMatrix, props, text,
byteLength, pos, scalarsPerPosition, offset));
if (blob) {
blob->flushThrowaway(atlasGlyphCache, target, props, fDistanceAdjustTable.get(), paint,
clip, viewMatrix, regionClipBounds, offset.fX, offset.fY);
}
return;
}
// fall back to drawing as a path or scaled glyph
GrTextUtils::DrawBigPosText(target, props, clip, paint, viewMatrix, text,
byteLength, pos, scalarsPerPosition, offset, regionClipBounds);
}
void GrAtlasTextContext::DrawBmpText(GrAtlasTextBlob* blob, int runIndex,
GrAtlasGlyphCache* fontCache, const SkSurfaceProps& props,
const GrTextUtils::Paint& paint,
SkScalerContextFlags scalerContextFlags,
const SkMatrix& viewMatrix, const char text[],
size_t byteLength, SkScalar x, SkScalar y) {
SkASSERT(byteLength == 0 || text != nullptr);
// nothing to draw
if (text == nullptr || byteLength == 0) {
return;
}
// Ensure the blob is set for bitmaptext
blob->setHasBitmap();
GrAtlasTextStrike* currStrike = nullptr;
SkGlyphCache* cache = blob->setupCache(runIndex, props, scalerContextFlags, paint, &viewMatrix);
SkFindAndPlaceGlyph::ProcessText(paint.skPaint().getTextEncoding(), text, byteLength, {x, y},
viewMatrix, paint.skPaint().getTextAlign(), cache,
[&](const SkGlyph& glyph, SkPoint position, SkPoint rounding) {
position += rounding;
BmpAppendGlyph(blob, runIndex, fontCache, &currStrike,
glyph, SkScalarFloorToScalar(position.fX),
SkScalarFloorToScalar(position.fY),
paint.filteredPremulColor(), cache,
SK_Scalar1);
});
SkGlyphCache::AttachCache(cache);
}
void GrAtlasTextContext::DrawBmpPosText(GrAtlasTextBlob* blob, int runIndex,
GrAtlasGlyphCache* fontCache, const SkSurfaceProps& props,
const GrTextUtils::Paint& paint,
SkScalerContextFlags scalerContextFlags,
const SkMatrix& viewMatrix,
const char text[], size_t byteLength, const SkScalar pos[],
int scalarsPerPosition, const SkPoint& offset,
SkScalar textRatio) {
SkASSERT(byteLength == 0 || text != nullptr);
SkASSERT(1 == scalarsPerPosition || 2 == scalarsPerPosition);
// nothing to draw
if (text == nullptr || byteLength == 0) {
return;
}
// Ensure the blob is set for bitmaptext
blob->setHasBitmap();
GrAtlasTextStrike* currStrike = nullptr;
SkGlyphCache* cache = blob->setupCache(runIndex, props, scalerContextFlags, paint, &viewMatrix);
SkFindAndPlaceGlyph::ProcessPosText(
paint.skPaint().getTextEncoding(), text, byteLength, offset, viewMatrix, pos,
scalarsPerPosition, paint.skPaint().getTextAlign(), cache,
[&](const SkGlyph& glyph, SkPoint position, SkPoint rounding) {
position += rounding;
BmpAppendGlyph(blob, runIndex, fontCache, &currStrike, glyph,
SkScalarFloorToScalar(position.fX),
SkScalarFloorToScalar(position.fY),
paint.filteredPremulColor(), cache, textRatio);
});
SkGlyphCache::AttachCache(cache);
}
void GrAtlasTextContext::BmpAppendGlyph(GrAtlasTextBlob* blob, int runIndex,
GrAtlasGlyphCache* fontCache, GrAtlasTextStrike** strike,
const SkGlyph& skGlyph, SkScalar sx, SkScalar sy,
GrColor color, SkGlyphCache* glyphCache,
SkScalar textRatio) {
if (!*strike) {
*strike = fontCache->getStrike(glyphCache);
}
GrGlyph::PackedID id = GrGlyph::Pack(skGlyph.getGlyphID(),
skGlyph.getSubXFixed(),
skGlyph.getSubYFixed(),
GrGlyph::kCoverage_MaskStyle);
GrGlyph* glyph = (*strike)->getGlyph(skGlyph, id, glyphCache);
if (!glyph) {
return;
}
SkASSERT(skGlyph.fWidth == glyph->width());
SkASSERT(skGlyph.fHeight == glyph->height());
SkScalar dx = SkIntToScalar(glyph->fBounds.fLeft);
SkScalar dy = SkIntToScalar(glyph->fBounds.fTop);
SkScalar width = SkIntToScalar(glyph->fBounds.width());
SkScalar height = SkIntToScalar(glyph->fBounds.height());
dx *= textRatio;
dy *= textRatio;
width *= textRatio;
height *= textRatio;
SkRect glyphRect = SkRect::MakeXYWH(sx + dx, sy + dy, width, height);
blob->appendGlyph(runIndex, glyphRect, color, *strike, glyph, glyphCache, skGlyph, sx, sy,
textRatio, true);
}
bool GrAtlasTextContext::canDrawAsDistanceFields(const SkPaint& skPaint, const SkMatrix& viewMatrix,
const SkSurfaceProps& props,
const GrShaderCaps& caps) const {
if (!viewMatrix.hasPerspective()) {
SkScalar maxScale = viewMatrix.getMaxScale();
SkScalar scaledTextSize = maxScale * skPaint.getTextSize();
// Hinted text looks far better at small resolutions
// Scaling up beyond 2x yields undesireable artifacts
if (scaledTextSize < fMinDistanceFieldFontSize ||
scaledTextSize > fMaxDistanceFieldFontSize) {
return false;
}
bool useDFT = props.isUseDeviceIndependentFonts();
#if SK_FORCE_DISTANCE_FIELD_TEXT
useDFT = true;
#endif
if (!useDFT && scaledTextSize < kLargeDFFontSize) {
return false;
}
}
// mask filters modify alpha, which doesn't translate well to distance
if (skPaint.getMaskFilter() || !caps.shaderDerivativeSupport()) {
return false;
}
// TODO: add some stroking support
if (skPaint.getStyle() != SkPaint::kFill_Style) {
return false;
}
return true;
}
void GrAtlasTextContext::initDistanceFieldPaint(GrAtlasTextBlob* blob,
SkPaint* skPaint,
SkScalar* textRatio,
const SkMatrix& viewMatrix) const {
SkScalar textSize = skPaint->getTextSize();
SkScalar scaledTextSize = textSize;
if (viewMatrix.hasPerspective()) {
// for perspective, we simply force to the medium size
// TODO: compute a size based on approximate screen area
scaledTextSize = kMediumDFFontLimit;
} else {
SkScalar maxScale = viewMatrix.getMaxScale();
// if we have non-unity scale, we need to choose our base text size
// based on the SkPaint's text size multiplied by the max scale factor
// TODO: do we need to do this if we're scaling down (i.e. maxScale < 1)?
if (maxScale > 0 && !SkScalarNearlyEqual(maxScale, SK_Scalar1)) {
scaledTextSize *= maxScale;
}
}
// We have three sizes of distance field text, and within each size 'bucket' there is a floor
// and ceiling. A scale outside of this range would require regenerating the distance fields
SkScalar dfMaskScaleFloor;
SkScalar dfMaskScaleCeil;
if (scaledTextSize <= kSmallDFFontLimit) {
dfMaskScaleFloor = fMinDistanceFieldFontSize;
dfMaskScaleCeil = kSmallDFFontLimit;
*textRatio = textSize / kSmallDFFontSize;
skPaint->setTextSize(SkIntToScalar(kSmallDFFontSize));
} else if (scaledTextSize <= kMediumDFFontLimit) {
dfMaskScaleFloor = kSmallDFFontLimit;
dfMaskScaleCeil = kMediumDFFontLimit;
*textRatio = textSize / kMediumDFFontSize;
skPaint->setTextSize(SkIntToScalar(kMediumDFFontSize));
} else {
dfMaskScaleFloor = kMediumDFFontLimit;
dfMaskScaleCeil = fMaxDistanceFieldFontSize;
*textRatio = textSize / kLargeDFFontSize;
skPaint->setTextSize(SkIntToScalar(kLargeDFFontSize));
}
// Because there can be multiple runs in the blob, we want the overall maxMinScale, and
// minMaxScale to make regeneration decisions. Specifically, we want the maximum minimum scale
// we can tolerate before we'd drop to a lower mip size, and the minimum maximum scale we can
// tolerate before we'd have to move to a large mip size. When we actually test these values
// we look at the delta in scale between the new viewmatrix and the old viewmatrix, and test
// against these values to decide if we can reuse or not(ie, will a given scale change our mip
// level)
SkASSERT(dfMaskScaleFloor <= scaledTextSize && scaledTextSize <= dfMaskScaleCeil);
blob->setMinAndMaxScale(dfMaskScaleFloor / scaledTextSize, dfMaskScaleCeil / scaledTextSize);
skPaint->setAntiAlias(true);
skPaint->setLCDRenderText(false);
skPaint->setAutohinted(false);
skPaint->setHinting(SkPaint::kNormal_Hinting);
skPaint->setSubpixelText(true);
}
void GrAtlasTextContext::drawDFText(GrAtlasTextBlob* blob, int runIndex,
GrAtlasGlyphCache* fontCache, const SkSurfaceProps& props,
const GrTextUtils::Paint& paint,
SkScalerContextFlags scalerContextFlags,
const SkMatrix& viewMatrix, const char text[],
size_t byteLength, SkScalar x, SkScalar y) const {
SkASSERT(byteLength == 0 || text != nullptr);
// nothing to draw
if (text == nullptr || byteLength == 0) {
return;
}
const SkPaint& skPaint = paint.skPaint();
SkPaint::GlyphCacheProc glyphCacheProc =
SkPaint::GetGlyphCacheProc(skPaint.getTextEncoding(), skPaint.isDevKernText(), true);
SkAutoDescriptor desc;
SkScalerContextEffects effects;
// We apply the fake-gamma by altering the distance in the shader, so we ignore the
// passed-in scaler context flags. (It's only used when we fall-back to bitmap text).
SkScalerContext::CreateDescriptorAndEffectsUsingPaint(
skPaint, &props, SkScalerContextFlags::kNone, nullptr, &desc, &effects);
SkGlyphCache* origPaintCache =
SkGlyphCache::DetachCache(skPaint.getTypeface(), effects, desc.getDesc());
SkTArray<SkScalar> positions;
const char* textPtr = text;
SkScalar stopX = 0;
SkScalar stopY = 0;
SkScalar origin = 0;
switch (skPaint.getTextAlign()) {
case SkPaint::kRight_Align: origin = SK_Scalar1; break;
case SkPaint::kCenter_Align: origin = SK_ScalarHalf; break;
case SkPaint::kLeft_Align: origin = 0; break;
}
SkAutoKern autokern;
const char* stop = text + byteLength;
while (textPtr < stop) {
// don't need x, y here, since all subpixel variants will have the
// same advance
const SkGlyph& glyph = glyphCacheProc(origPaintCache, &textPtr);
SkScalar width = SkFloatToScalar(glyph.fAdvanceX) + autokern.adjust(glyph);
positions.push_back(stopX + origin * width);
SkScalar height = SkFloatToScalar(glyph.fAdvanceY);
positions.push_back(stopY + origin * height);
stopX += width;
stopY += height;
}
SkASSERT(textPtr == stop);
SkGlyphCache::AttachCache(origPaintCache);
// now adjust starting point depending on alignment
SkScalar alignX = stopX;
SkScalar alignY = stopY;
if (skPaint.getTextAlign() == SkPaint::kCenter_Align) {
alignX = SkScalarHalf(alignX);
alignY = SkScalarHalf(alignY);
} else if (skPaint.getTextAlign() == SkPaint::kLeft_Align) {
alignX = 0;
alignY = 0;
}
x -= alignX;
y -= alignY;
SkPoint offset = SkPoint::Make(x, y);
this->drawDFPosText(blob, runIndex, fontCache, props, paint, scalerContextFlags, viewMatrix,
text, byteLength, positions.begin(), 2, offset);
}
void GrAtlasTextContext::drawDFPosText(GrAtlasTextBlob* blob, int runIndex,
GrAtlasGlyphCache* fontCache, const SkSurfaceProps& props,
const GrTextUtils::Paint& paint,
SkScalerContextFlags scalerContextFlags,
const SkMatrix& viewMatrix, const char text[],
size_t byteLength, const SkScalar pos[],
int scalarsPerPosition, const SkPoint& offset) const {
SkASSERT(byteLength == 0 || text != nullptr);
SkASSERT(1 == scalarsPerPosition || 2 == scalarsPerPosition);
// nothing to draw
if (text == nullptr || byteLength == 0) {
return;
}
SkTDArray<char> fallbackTxt;
SkTDArray<SkScalar> fallbackPos;
SkTDArray<char> bigFallbackTxt;
SkTDArray<SkScalar> bigFallbackPos;
SkScalar textSize = paint.skPaint().getTextSize();
SkScalar maxTextSize = fontCache->getGlyphSizeLimit();
SkScalar bigFallbackTextSize = maxTextSize;
SkScalar maxScale = viewMatrix.getMaxScale();
bool hasWCoord = viewMatrix.hasPerspective() || fDistanceFieldVerticesAlwaysHaveW;
// Setup distance field paint and text ratio
SkScalar textRatio;
SkPaint dfPaint(paint);
this->initDistanceFieldPaint(blob, &dfPaint, &textRatio, viewMatrix);
blob->setHasDistanceField();
blob->setSubRunHasDistanceFields(runIndex, paint.skPaint().isLCDRenderText(),
paint.skPaint().isAntiAlias(), hasWCoord);
GrAtlasTextStrike* currStrike = nullptr;
// We apply the fake-gamma by altering the distance in the shader, so we ignore the
// passed-in scaler context flags. (It's only used when we fall-back to bitmap text).
SkGlyphCache* cache =
blob->setupCache(runIndex, props, SkScalerContextFlags::kNone, dfPaint, nullptr);
SkPaint::GlyphCacheProc glyphCacheProc =
SkPaint::GetGlyphCacheProc(dfPaint.getTextEncoding(), dfPaint.isDevKernText(), true);
const char* stop = text + byteLength;
SkPaint::Align align = dfPaint.getTextAlign();
SkScalar alignMul = SkPaint::kCenter_Align == align ? SK_ScalarHalf :
(SkPaint::kRight_Align == align ? SK_Scalar1 : 0);
while (text < stop) {
const char* lastText = text;
// the last 2 parameters are ignored
const SkGlyph& glyph = glyphCacheProc(cache, &text);
if (glyph.fWidth) {
SkScalar x = offset.x() + pos[0];
SkScalar y = offset.y() + (2 == scalarsPerPosition ? pos[1] : 0);
SkScalar advanceX = SkFloatToScalar(glyph.fAdvanceX) * alignMul * textRatio;
SkScalar advanceY = SkFloatToScalar(glyph.fAdvanceY) * alignMul * textRatio;
if (glyph.fMaskFormat != SkMask::kARGB32_Format) {
DfAppendGlyph(blob, runIndex, fontCache, &currStrike, glyph, x - advanceX,
y - advanceY, paint.filteredPremulColor(), cache, textRatio);
} else {
// can't append color glyph to SDF batch, send to fallback
SkScalar maxDim = SkTMax(glyph.fWidth, glyph.fHeight)*textRatio;
SkScalar scaledGlyphSize = maxDim*maxScale;
if (!viewMatrix.hasPerspective() && scaledGlyphSize > maxTextSize) {
bigFallbackTxt.append(SkToInt(text - lastText), lastText);
*bigFallbackPos.append() = maxScale*pos[0];
if (2 == scalarsPerPosition) {
*bigFallbackPos.append() = maxScale*pos[1];
}
SkScalar glyphTextSize = SkScalarFloorToScalar(maxTextSize*textSize/maxDim);
bigFallbackTextSize = SkTMin(glyphTextSize, bigFallbackTextSize);
} else {
fallbackTxt.append(SkToInt(text - lastText), lastText);
*fallbackPos.append() = pos[0];
if (2 == scalarsPerPosition) {
*fallbackPos.append() = pos[1];
}
}
}
}
pos += scalarsPerPosition;
}
SkGlyphCache::AttachCache(cache);
if (fallbackTxt.count()) {
blob->initOverride(runIndex);
GrAtlasTextContext::DrawBmpPosText(blob, runIndex, fontCache, props, paint,
scalerContextFlags, viewMatrix, fallbackTxt.begin(),
fallbackTxt.count(), fallbackPos.begin(),
scalarsPerPosition, offset, SK_Scalar1);
}
if (bigFallbackTxt.count()) {
// Set up paint and matrix to scale glyphs
blob->initOverride(runIndex);
SkPaint largePaint(paint);
largePaint.setTextSize(bigFallbackTextSize);
// remove maxScale from viewMatrix and move it into textRatio
// this keeps the base glyph size consistent regardless of matrix scale
SkMatrix modMatrix(viewMatrix);
SkScalar invScale = SkScalarInvert(maxScale);
modMatrix.preScale(invScale, invScale);
SkScalar bigFallbackTextRatio = textSize*maxScale/bigFallbackTextSize;
SkPoint modOffset(offset);
modOffset *= maxScale;
GrTextUtils::Paint textPaint(&largePaint, paint.dstColorSpaceInfo());
GrAtlasTextContext::DrawBmpPosText(blob, runIndex, fontCache, props, textPaint,
scalerContextFlags, modMatrix, bigFallbackTxt.begin(),
bigFallbackTxt.count(), bigFallbackPos.begin(),
scalarsPerPosition, modOffset, bigFallbackTextRatio);
}
}
// TODO: merge with BmpAppendGlyph
void GrAtlasTextContext::DfAppendGlyph(GrAtlasTextBlob* blob, int runIndex,
GrAtlasGlyphCache* cache, GrAtlasTextStrike** strike,
const SkGlyph& skGlyph, SkScalar sx, SkScalar sy,
GrColor color, SkGlyphCache* glyphCache,
SkScalar textRatio) {
if (!*strike) {
*strike = cache->getStrike(glyphCache);
}
GrGlyph::PackedID id = GrGlyph::Pack(skGlyph.getGlyphID(),
skGlyph.getSubXFixed(),
skGlyph.getSubYFixed(),
GrGlyph::kDistance_MaskStyle);
GrGlyph* glyph = (*strike)->getGlyph(skGlyph, id, glyphCache);
if (!glyph) {
return;
}
SkScalar dx = SkIntToScalar(glyph->fBounds.fLeft + SK_DistanceFieldInset);
SkScalar dy = SkIntToScalar(glyph->fBounds.fTop + SK_DistanceFieldInset);
SkScalar width = SkIntToScalar(glyph->fBounds.width() - 2 * SK_DistanceFieldInset);
SkScalar height = SkIntToScalar(glyph->fBounds.height() - 2 * SK_DistanceFieldInset);
dx *= textRatio;
dy *= textRatio;
width *= textRatio;
height *= textRatio;
SkRect glyphRect = SkRect::MakeXYWH(sx + dx, sy + dy, width, height);
blob->appendGlyph(runIndex, glyphRect, color, *strike, glyph, glyphCache, skGlyph, sx, sy,
textRatio, false);
}
///////////////////////////////////////////////////////////////////////////////////////////////////
#if GR_TEST_UTILS
#include "GrRenderTargetContext.h"
GR_DRAW_OP_TEST_DEFINE(GrAtlasTextOp) {
static uint32_t gContextID = SK_InvalidGenID;
static std::unique_ptr<GrAtlasTextContext> gTextContext;
static SkSurfaceProps gSurfaceProps(SkSurfaceProps::kLegacyFontHost_InitType);
if (context->uniqueID() != gContextID) {
gContextID = context->uniqueID();
gTextContext = GrAtlasTextContext::Make(GrAtlasTextContext::Options());
}
// Setup dummy SkPaint / GrPaint / GrRenderTargetContext
sk_sp<GrRenderTargetContext> rtc(context->makeDeferredRenderTargetContext(
SkBackingFit::kApprox, 1024, 1024, kRGBA_8888_GrPixelConfig, nullptr));
SkMatrix viewMatrix = GrTest::TestMatrixInvertible(random);
// Because we the GrTextUtils::Paint requires an SkPaint for font info, we ignore the GrPaint
// param.
SkPaint skPaint;
skPaint.setColor(random->nextU());
skPaint.setLCDRenderText(random->nextBool());
skPaint.setAntiAlias(skPaint.isLCDRenderText() ? true : random->nextBool());
skPaint.setSubpixelText(random->nextBool());
GrTextUtils::Paint utilsPaint(&skPaint, &rtc->colorSpaceInfo());
const char* text = "The quick brown fox jumps over the lazy dog.";
int textLen = (int)strlen(text);
// create some random x/y offsets, including negative offsets
static const int kMaxTrans = 1024;
int xPos = (random->nextU() % 2) * 2 - 1;
int yPos = (random->nextU() % 2) * 2 - 1;
int xInt = (random->nextU() % kMaxTrans) * xPos;
int yInt = (random->nextU() % kMaxTrans) * yPos;
SkScalar x = SkIntToScalar(xInt);
SkScalar y = SkIntToScalar(yInt);
auto atlasGlyphCache = context->contextPriv().getAtlasGlyphCache();
// right now we don't handle textblobs, nor do we handle drawPosText. Since we only intend to
// test the text op with this unit test, that is okay.
sk_sp<GrAtlasTextBlob> blob(gTextContext->makeDrawTextBlob(
context->contextPriv().getTextBlobCache(), atlasGlyphCache,
*context->caps()->shaderCaps(), utilsPaint,
GrAtlasTextContext::kTextBlobOpScalerContextFlags, viewMatrix, gSurfaceProps, text,
static_cast<size_t>(textLen), x, y));
return blob->test_makeOp(textLen, 0, 0, viewMatrix, x, y, utilsPaint, gSurfaceProps,
gTextContext->dfAdjustTable(), atlasGlyphCache,
rtc->textTarget());
}
#endif