| /* |
| * 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 "GrTextUtils.h" |
| |
| #include "GrAtlasTextBlob.h" |
| #include "GrBatchFontCache.h" |
| #include "GrBlurUtils.h" |
| #include "GrCaps.h" |
| #include "GrContext.h" |
| #include "GrRenderTargetContext.h" |
| |
| #include "SkDistanceFieldGen.h" |
| #include "SkDrawProcs.h" |
| #include "SkFindAndPlaceGlyph.h" |
| #include "SkGlyphCache.h" |
| #include "SkPaint.h" |
| #include "SkRect.h" |
| #include "SkTextMapStateProc.h" |
| #include "SkTextToPathIter.h" |
| |
| namespace { |
| static const int kMinDFFontSize = 18; |
| 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; |
| #ifdef SK_BUILD_FOR_ANDROID |
| static const int kLargeDFFontLimit = 384; |
| #else |
| static const int kLargeDFFontLimit = 2 * kLargeDFFontSize; |
| #endif |
| }; |
| |
| void GrTextUtils::DrawBmpText(GrAtlasTextBlob* blob, int runIndex, |
| GrBatchFontCache* fontCache, |
| const SkSurfaceProps& props, const SkPaint& skPaint, |
| GrColor color, uint32_t 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(); |
| |
| GrBatchTextStrike* currStrike = nullptr; |
| |
| SkGlyphCache* cache = blob->setupCache(runIndex, props, scalerContextFlags, skPaint, |
| &viewMatrix); |
| SkFindAndPlaceGlyph::ProcessText( |
| skPaint.getTextEncoding(), text, byteLength, |
| {x, y}, viewMatrix, skPaint.getTextAlign(), |
| cache, |
| [&](const SkGlyph& glyph, SkPoint position, SkPoint rounding) { |
| position += rounding; |
| BmpAppendGlyph( |
| blob, runIndex, fontCache, &currStrike, glyph, |
| SkScalarFloorToInt(position.fX), SkScalarFloorToInt(position.fY), |
| color, cache); |
| } |
| ); |
| |
| SkGlyphCache::AttachCache(cache); |
| } |
| |
| void GrTextUtils::DrawBmpPosText(GrAtlasTextBlob* blob, int runIndex, |
| GrBatchFontCache* fontCache, |
| const SkSurfaceProps& props, const SkPaint& skPaint, |
| GrColor color, uint32_t scalerContextFlags, |
| const SkMatrix& viewMatrix, |
| const char text[], size_t byteLength, |
| const SkScalar pos[], int scalarsPerPosition, |
| const SkPoint& offset) { |
| 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(); |
| |
| GrBatchTextStrike* currStrike = nullptr; |
| |
| SkGlyphCache* cache = blob->setupCache(runIndex, props, scalerContextFlags, skPaint, |
| &viewMatrix); |
| |
| SkFindAndPlaceGlyph::ProcessPosText( |
| skPaint.getTextEncoding(), text, byteLength, |
| offset, viewMatrix, pos, scalarsPerPosition, |
| skPaint.getTextAlign(), cache, |
| [&](const SkGlyph& glyph, SkPoint position, SkPoint rounding) { |
| position += rounding; |
| BmpAppendGlyph( |
| blob, runIndex, fontCache, &currStrike, glyph, |
| SkScalarFloorToInt(position.fX), SkScalarFloorToInt(position.fY), |
| color, cache); |
| } |
| ); |
| |
| SkGlyphCache::AttachCache(cache); |
| } |
| |
| void GrTextUtils::BmpAppendGlyph(GrAtlasTextBlob* blob, int runIndex, |
| GrBatchFontCache* fontCache, |
| GrBatchTextStrike** strike, const SkGlyph& skGlyph, |
| int vx, int vy, GrColor color, SkGlyphCache* cache) { |
| if (!*strike) { |
| *strike = fontCache->getStrike(cache); |
| } |
| |
| GrGlyph::PackedID id = GrGlyph::Pack(skGlyph.getGlyphID(), |
| skGlyph.getSubXFixed(), |
| skGlyph.getSubYFixed(), |
| GrGlyph::kCoverage_MaskStyle); |
| GrGlyph* glyph = (*strike)->getGlyph(skGlyph, id, cache); |
| if (!glyph) { |
| return; |
| } |
| |
| int x = vx + glyph->fBounds.fLeft; |
| int y = vy + glyph->fBounds.fTop; |
| |
| // keep them as ints until we've done the clip-test |
| int width = glyph->fBounds.width(); |
| int height = glyph->fBounds.height(); |
| |
| SkRect r; |
| r.fLeft = SkIntToScalar(x); |
| r.fTop = SkIntToScalar(y); |
| r.fRight = r.fLeft + SkIntToScalar(width); |
| r.fBottom = r.fTop + SkIntToScalar(height); |
| |
| blob->appendGlyph(runIndex, r, color, *strike, glyph, cache, skGlyph, |
| SkIntToScalar(vx), SkIntToScalar(vy), 1.0f, false); |
| } |
| |
| bool GrTextUtils::CanDrawAsDistanceFields(const SkPaint& skPaint, const SkMatrix& viewMatrix, |
| const SkSurfaceProps& props, const GrShaderCaps& caps) { |
| // TODO: support perspective (need getMaxScale replacement) |
| if (viewMatrix.hasPerspective()) { |
| return false; |
| } |
| |
| 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 < kMinDFFontSize || |
| scaledTextSize > kLargeDFFontLimit) { |
| return false; |
| } |
| |
| bool useDFT = props.isUseDeviceIndependentFonts(); |
| #if SK_FORCE_DISTANCE_FIELD_TEXT |
| useDFT = true; |
| #endif |
| |
| if (!useDFT && scaledTextSize < kLargeDFFontSize) { |
| return false; |
| } |
| |
| // rasterizers and mask filters modify alpha, which doesn't |
| // translate well to distance |
| if (skPaint.getRasterizer() || skPaint.getMaskFilter() || !caps.shaderDerivativeSupport()) { |
| return false; |
| } |
| |
| // TODO: add some stroking support |
| if (skPaint.getStyle() != SkPaint::kFill_Style) { |
| return false; |
| } |
| |
| return true; |
| } |
| |
| void GrTextUtils::InitDistanceFieldPaint(GrAtlasTextBlob* blob, |
| SkPaint* skPaint, |
| SkScalar* textRatio, |
| const SkMatrix& viewMatrix) { |
| // getMaxScale doesn't support perspective, so neither do we at the moment |
| SkASSERT(!viewMatrix.hasPerspective()); |
| SkScalar maxScale = viewMatrix.getMaxScale(); |
| SkScalar textSize = skPaint->getTextSize(); |
| SkScalar scaledTextSize = textSize; |
| // 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 = kMinDFFontSize; |
| 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 = kLargeDFFontLimit; |
| *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->setLCDRenderText(false); |
| skPaint->setAutohinted(false); |
| skPaint->setHinting(SkPaint::kNormal_Hinting); |
| skPaint->setSubpixelText(true); |
| } |
| |
| void GrTextUtils::DrawDFText(GrAtlasTextBlob* blob, int runIndex, |
| GrBatchFontCache* fontCache, const SkSurfaceProps& props, |
| const SkPaint& skPaint, GrColor color, uint32_t 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; |
| } |
| |
| 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). |
| skPaint.getScalerContextDescriptor(&effects, &desc, props, SkPaint::kNone_ScalerContextFlags, |
| nullptr); |
| 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); |
| |
| DrawDFPosText(blob, runIndex, fontCache, props, skPaint, color, scalerContextFlags, viewMatrix, |
| text, byteLength, positions.begin(), 2, offset); |
| } |
| |
| void GrTextUtils::DrawDFPosText(GrAtlasTextBlob* blob, int runIndex, |
| GrBatchFontCache* fontCache, const SkSurfaceProps& props, |
| const SkPaint& origPaint, |
| GrColor color, uint32_t scalerContextFlags, |
| const SkMatrix& viewMatrix, |
| const char text[], size_t byteLength, |
| const SkScalar pos[], int scalarsPerPosition, |
| const SkPoint& offset) { |
| 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; |
| |
| // Setup distance field paint and text ratio |
| SkScalar textRatio; |
| SkPaint dfPaint(origPaint); |
| GrTextUtils::InitDistanceFieldPaint(blob, &dfPaint, &textRatio, viewMatrix); |
| blob->setHasDistanceField(); |
| blob->setSubRunHasDistanceFields(runIndex, origPaint.isLCDRenderText()); |
| |
| GrBatchTextStrike* 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, SkPaint::kNone_ScalerContextFlags, |
| dfPaint, nullptr); |
| SkPaint::GlyphCacheProc glyphCacheProc = SkPaint::GetGlyphCacheProc(dfPaint.getTextEncoding(), |
| dfPaint.isDevKernText(), |
| true); |
| |
| const char* stop = text + byteLength; |
| |
| if (SkPaint::kLeft_Align == dfPaint.getTextAlign()) { |
| 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); |
| |
| if (!DfAppendGlyph(blob, |
| runIndex, |
| fontCache, |
| &currStrike, |
| glyph, |
| x, y, color, cache, |
| textRatio, viewMatrix)) { |
| // couldn't append, send to fallback |
| fallbackTxt.append(SkToInt(text-lastText), lastText); |
| *fallbackPos.append() = pos[0]; |
| if (2 == scalarsPerPosition) { |
| *fallbackPos.append() = pos[1]; |
| } |
| } |
| } |
| pos += scalarsPerPosition; |
| } |
| } else { |
| SkScalar alignMul = SkPaint::kCenter_Align == dfPaint.getTextAlign() ? SK_ScalarHalf |
| : SK_Scalar1; |
| 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 (!DfAppendGlyph(blob, |
| runIndex, |
| fontCache, |
| &currStrike, |
| glyph, |
| x - advanceX, y - advanceY, color, |
| cache, |
| textRatio, |
| viewMatrix)) { |
| // couldn't append, send to fallback |
| 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); |
| GrTextUtils::DrawBmpPosText(blob, runIndex, fontCache, props, |
| origPaint, origPaint.getColor(), scalerContextFlags, viewMatrix, |
| fallbackTxt.begin(), fallbackTxt.count(), |
| fallbackPos.begin(), scalarsPerPosition, offset); |
| } |
| } |
| |
| bool GrTextUtils::DfAppendGlyph(GrAtlasTextBlob* blob, int runIndex, GrBatchFontCache* cache, |
| GrBatchTextStrike** strike, const SkGlyph& skGlyph, |
| SkScalar sx, SkScalar sy, GrColor color, |
| SkGlyphCache* glyphCache, |
| SkScalar textRatio, const SkMatrix& viewMatrix) { |
| 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 true; |
| } |
| |
| // fallback to color glyph support |
| if (kA8_GrMaskFormat != glyph->fMaskFormat) { |
| return false; |
| } |
| |
| 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); |
| |
| SkScalar scale = textRatio; |
| dx *= scale; |
| dy *= scale; |
| width *= scale; |
| height *= scale; |
| sx += dx; |
| sy += dy; |
| SkRect glyphRect = SkRect::MakeXYWH(sx, sy, width, height); |
| |
| blob->appendGlyph(runIndex, glyphRect, color, *strike, glyph, glyphCache, skGlyph, |
| sx - dx, sy - dy, scale, true); |
| return true; |
| } |
| |
| void GrTextUtils::DrawTextAsPath(GrContext* context, GrRenderTargetContext* rtc, |
| const GrClip& clip, |
| const SkPaint& skPaint, const SkMatrix& viewMatrix, |
| const char text[], size_t byteLength, SkScalar x, SkScalar y, |
| const SkIRect& clipBounds) { |
| SkTextToPathIter iter(text, byteLength, skPaint, true); |
| |
| SkMatrix matrix; |
| matrix.setScale(iter.getPathScale(), iter.getPathScale()); |
| matrix.postTranslate(x, y); |
| |
| const SkPath* iterPath; |
| SkScalar xpos, prevXPos = 0; |
| |
| while (iter.next(&iterPath, &xpos)) { |
| matrix.postTranslate(xpos - prevXPos, 0); |
| if (iterPath) { |
| const SkPaint& pnt = iter.getPaint(); |
| GrBlurUtils::drawPathWithMaskFilter(context, rtc, clip, *iterPath, |
| pnt, viewMatrix, &matrix, clipBounds, false); |
| } |
| prevXPos = xpos; |
| } |
| } |
| |
| void GrTextUtils::DrawPosTextAsPath(GrContext* context, |
| GrRenderTargetContext* rtc, |
| const SkSurfaceProps& props, |
| const GrClip& clip, |
| const SkPaint& origPaint, const SkMatrix& viewMatrix, |
| const char text[], size_t byteLength, |
| const SkScalar pos[], int scalarsPerPosition, |
| const SkPoint& offset, const SkIRect& clipBounds) { |
| // setup our std paint, in hopes of getting hits in the cache |
| SkPaint paint(origPaint); |
| SkScalar matrixScale = paint.setupForAsPaths(); |
| |
| SkMatrix matrix; |
| matrix.setScale(matrixScale, matrixScale); |
| |
| // Temporarily jam in kFill, so we only ever ask for the raw outline from the cache. |
| paint.setStyle(SkPaint::kFill_Style); |
| paint.setPathEffect(nullptr); |
| |
| SkPaint::GlyphCacheProc glyphCacheProc = SkPaint::GetGlyphCacheProc(paint.getTextEncoding(), |
| paint.isDevKernText(), |
| true); |
| SkAutoGlyphCache autoCache(paint, &props, nullptr); |
| SkGlyphCache* cache = autoCache.getCache(); |
| |
| const char* stop = text + byteLength; |
| SkTextAlignProc alignProc(paint.getTextAlign()); |
| SkTextMapStateProc tmsProc(SkMatrix::I(), offset, scalarsPerPosition); |
| |
| // Now restore the original settings, so we "draw" with whatever style/stroking. |
| paint.setStyle(origPaint.getStyle()); |
| paint.setPathEffect(sk_ref_sp(origPaint.getPathEffect())); |
| |
| while (text < stop) { |
| const SkGlyph& glyph = glyphCacheProc(cache, &text); |
| if (glyph.fWidth) { |
| const SkPath* path = cache->findPath(glyph); |
| if (path) { |
| SkPoint tmsLoc; |
| tmsProc(pos, &tmsLoc); |
| SkPoint loc; |
| alignProc(tmsLoc, glyph, &loc); |
| |
| matrix[SkMatrix::kMTransX] = loc.fX; |
| matrix[SkMatrix::kMTransY] = loc.fY; |
| GrBlurUtils::drawPathWithMaskFilter(context, rtc, clip, *path, paint, |
| viewMatrix, &matrix, clipBounds, false); |
| } |
| } |
| pos += scalarsPerPosition; |
| } |
| } |
| |
| bool GrTextUtils::ShouldDisableLCD(const SkPaint& paint) { |
| return paint.getMaskFilter() || |
| paint.getRasterizer() || |
| paint.getPathEffect() || |
| paint.isFakeBoldText() || |
| paint.getStyle() != SkPaint::kFill_Style; |
| } |
| |
| uint32_t GrTextUtils::FilterTextFlags(const SkSurfaceProps& surfaceProps, const SkPaint& paint) { |
| uint32_t flags = paint.getFlags(); |
| |
| if (!paint.isLCDRenderText() || !paint.isAntiAlias()) { |
| return flags; |
| } |
| |
| if (kUnknown_SkPixelGeometry == surfaceProps.pixelGeometry() || ShouldDisableLCD(paint)) { |
| flags &= ~SkPaint::kLCDRenderText_Flag; |
| flags |= SkPaint::kGenA8FromLCD_Flag; |
| } |
| |
| return flags; |
| } |