| /* |
| * Copyright 2014 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "GrStencilAndCoverTextContext.h" |
| #include "GrDrawTarget.h" |
| #include "GrFontScaler.h" |
| #include "GrGpu.h" |
| #include "GrPath.h" |
| #include "GrTextStrike.h" |
| #include "GrTextStrike_impl.h" |
| #include "SkAutoKern.h" |
| #include "SkDraw.h" |
| #include "SkDrawProcs.h" |
| #include "SkGlyphCache.h" |
| #include "SkGpuDevice.h" |
| #include "SkPath.h" |
| #include "SkTextMapStateProc.h" |
| |
| static const int kMaxReservedGlyphs = 64; |
| |
| GrStencilAndCoverTextContext::GrStencilAndCoverTextContext( |
| GrContext* context, const SkDeviceProperties& properties) |
| : GrTextContext(context, properties) |
| , fStroke(SkStrokeRec::kFill_InitStyle) { |
| } |
| |
| GrStencilAndCoverTextContext::~GrStencilAndCoverTextContext() { |
| } |
| |
| void GrStencilAndCoverTextContext::drawText(const GrPaint& paint, |
| const SkPaint& skPaint, |
| const char text[], |
| size_t byteLength, |
| SkScalar x, SkScalar y) { |
| SkASSERT(byteLength == 0 || text != NULL); |
| |
| if (text == NULL || byteLength == 0 /*|| fRC->isEmpty()*/) { |
| return; |
| } |
| |
| // This is the slow path, mainly used by Skia unit tests. The other |
| // backends (8888, gpu, ...) use device-space dependent glyph caches. In |
| // order to match the glyph positions that the other code paths produce, we |
| // must also use device-space dependent glyph cache. This has the |
| // side-effect that the glyph shape outline will be in device-space, |
| // too. This in turn has the side-effect that NVPR can not stroke the paths, |
| // as the stroke in NVPR is defined in object-space. |
| // NOTE: here we have following coincidence that works at the moment: |
| // - When using the device-space glyphs, the transforms we pass to NVPR |
| // instanced drawing are the global transforms, and the view transform is |
| // identity. NVPR can not use non-affine transforms in the instanced |
| // drawing. This is taken care of by SkDraw::ShouldDrawTextAsPaths since it |
| // will turn off the use of device-space glyphs when perspective transforms |
| // are in use. |
| |
| fGlyphTransform = fContext->getMatrix(); |
| |
| this->init(paint, skPaint, byteLength); |
| |
| SkMatrix* glyphCacheTransform = NULL; |
| // Transform our starting point. |
| if (fNeedsDeviceSpaceGlyphs) { |
| SkPoint loc; |
| fGlyphTransform.mapXY(x, y, &loc); |
| x = loc.fX; |
| y = loc.fY; |
| glyphCacheTransform = &fGlyphTransform; |
| } |
| |
| SkDrawCacheProc glyphCacheProc = fSkPaint.getDrawCacheProc(); |
| SkAutoGlyphCache autoCache(fSkPaint, &fDeviceProperties, glyphCacheTransform); |
| SkGlyphCache* cache = autoCache.getCache(); |
| GrFontScaler* scaler = GetGrFontScaler(cache); |
| GrTextStrike* strike = |
| fContext->getFontCache()->getStrike(scaler, true); |
| |
| const char* stop = text + byteLength; |
| |
| // Measure first if needed. |
| if (fSkPaint.getTextAlign() != SkPaint::kLeft_Align) { |
| SkFixed stopX = 0; |
| SkFixed stopY = 0; |
| |
| const char* textPtr = text; |
| while (textPtr < stop) { |
| // We don't need x, y here, since all subpixel variants will have the |
| // same advance. |
| const SkGlyph& glyph = glyphCacheProc(cache, &textPtr, 0, 0); |
| |
| stopX += glyph.fAdvanceX; |
| stopY += glyph.fAdvanceY; |
| } |
| SkASSERT(textPtr == stop); |
| |
| SkScalar alignX = SkFixedToScalar(stopX) * fTextRatio; |
| SkScalar alignY = SkFixedToScalar(stopY) * fTextRatio; |
| |
| if (fSkPaint.getTextAlign() == SkPaint::kCenter_Align) { |
| alignX = SkScalarHalf(alignX); |
| alignY = SkScalarHalf(alignY); |
| } |
| |
| x -= alignX; |
| y -= alignY; |
| } |
| |
| SkAutoKern autokern; |
| |
| SkFixed fixedSizeRatio = SkScalarToFixed(fTextRatio); |
| |
| SkFixed fx = SkScalarToFixed(x); |
| SkFixed fy = SkScalarToFixed(y); |
| while (text < stop) { |
| const SkGlyph& glyph = glyphCacheProc(cache, &text, 0, 0); |
| fx += SkFixedMul_portable(autokern.adjust(glyph), fixedSizeRatio); |
| if (glyph.fWidth) { |
| this->appendGlyph(GrGlyph::Pack(glyph.getGlyphID(), |
| glyph.getSubXFixed(), |
| glyph.getSubYFixed()), |
| SkPoint::Make( |
| SkFixedToScalar(fx), |
| SkFixedToScalar(fy)), |
| strike, |
| scaler); |
| } |
| |
| fx += SkFixedMul_portable(glyph.fAdvanceX, fixedSizeRatio); |
| fy += SkFixedMul_portable(glyph.fAdvanceY, fixedSizeRatio); |
| } |
| |
| this->finish(); |
| } |
| |
| void GrStencilAndCoverTextContext::drawPosText(const GrPaint& paint, |
| const SkPaint& skPaint, |
| const char text[], |
| size_t byteLength, |
| const SkScalar pos[], |
| SkScalar constY, |
| int scalarsPerPosition) { |
| SkASSERT(byteLength == 0 || text != NULL); |
| SkASSERT(1 == scalarsPerPosition || 2 == scalarsPerPosition); |
| |
| // nothing to draw |
| if (text == NULL || byteLength == 0/* || fRC->isEmpty()*/) { |
| return; |
| } |
| |
| // This is the fast path. Here we do not bake in the device-transform to |
| // the glyph outline or the advances. This is because we do not need to |
| // position the glyphs at all, since the caller has done the positioning. |
| // The positioning is based on SkPaint::measureText of individual |
| // glyphs. That already uses glyph cache without device transforms. Device |
| // transform is not part of SkPaint::measureText API, and thus we use the |
| // same glyphs as what were measured. |
| fGlyphTransform.reset(); |
| |
| this->init(paint, skPaint, byteLength); |
| |
| SkDrawCacheProc glyphCacheProc = fSkPaint.getDrawCacheProc(); |
| |
| SkAutoGlyphCache autoCache(fSkPaint, &fDeviceProperties, NULL); |
| SkGlyphCache* cache = autoCache.getCache(); |
| GrFontScaler* scaler = GetGrFontScaler(cache); |
| GrTextStrike* strike = |
| fContext->getFontCache()->getStrike(scaler, true); |
| |
| const char* stop = text + byteLength; |
| SkTextAlignProcScalar alignProc(fSkPaint.getTextAlign()); |
| SkTextMapStateProc tmsProc(SkMatrix::I(), constY, scalarsPerPosition); |
| |
| if (SkPaint::kLeft_Align == fSkPaint.getTextAlign()) { |
| while (text < stop) { |
| SkPoint loc; |
| tmsProc(pos, &loc); |
| const SkGlyph& glyph = glyphCacheProc(cache, &text, 0, 0); |
| if (glyph.fWidth) { |
| this->appendGlyph(GrGlyph::Pack(glyph.getGlyphID(), |
| glyph.getSubXFixed(), |
| glyph.getSubYFixed()), |
| loc, |
| strike, |
| scaler); |
| } |
| pos += scalarsPerPosition; |
| } |
| } else { |
| while (text < stop) { |
| const SkGlyph& glyph = glyphCacheProc(cache, &text, 0, 0); |
| if (glyph.fWidth) { |
| SkPoint tmsLoc; |
| tmsProc(pos, &tmsLoc); |
| SkPoint loc; |
| alignProc(tmsLoc, glyph, &loc); |
| |
| this->appendGlyph(GrGlyph::Pack(glyph.getGlyphID(), |
| glyph.getSubXFixed(), |
| glyph.getSubYFixed()), |
| loc, |
| strike, |
| scaler); |
| |
| } |
| pos += scalarsPerPosition; |
| } |
| } |
| |
| this->finish(); |
| } |
| |
| bool GrStencilAndCoverTextContext::canDraw(const SkPaint& paint) { |
| if (paint.getRasterizer()) { |
| return false; |
| } |
| if (paint.getMaskFilter()) { |
| return false; |
| } |
| if (paint.getPathEffect()) { |
| return false; |
| } |
| |
| // No hairlines unless we can map the 1 px width to the object space. |
| if (paint.getStyle() == SkPaint::kStroke_Style |
| && paint.getStrokeWidth() == 0 |
| && fContext->getMatrix().hasPerspective()) { |
| return false; |
| } |
| |
| // No color bitmap fonts. |
| SkScalerContext::Rec rec; |
| SkScalerContext::MakeRec(paint, &fDeviceProperties, NULL, &rec); |
| return rec.getFormat() != SkMask::kARGB32_Format; |
| } |
| |
| void GrStencilAndCoverTextContext::init(const GrPaint& paint, |
| const SkPaint& skPaint, |
| size_t textByteLength) { |
| GrTextContext::init(paint, skPaint); |
| |
| bool otherBackendsWillDrawAsPaths = |
| SkDraw::ShouldDrawTextAsPaths(skPaint, fContext->getMatrix()); |
| |
| if (otherBackendsWillDrawAsPaths) { |
| // This is to reproduce SkDraw::drawText_asPaths glyph positions. |
| fSkPaint.setLinearText(true); |
| fTextRatio = fSkPaint.getTextSize() / SkPaint::kCanonicalTextSizeForPaths; |
| fSkPaint.setTextSize(SkIntToScalar(SkPaint::kCanonicalTextSizeForPaths)); |
| if (fSkPaint.getStyle() != SkPaint::kFill_Style) { |
| // Compensate the glyphs being scaled up by fTextRatio by scaling the |
| // stroke down. |
| fSkPaint.setStrokeWidth(fSkPaint.getStrokeWidth() / fTextRatio); |
| } |
| fNeedsDeviceSpaceGlyphs = false; |
| } else { |
| fTextRatio = 1.0f; |
| fNeedsDeviceSpaceGlyphs = (fGlyphTransform.getType() & |
| (SkMatrix::kScale_Mask | SkMatrix::kAffine_Mask)) != 0; |
| // SkDraw::ShouldDrawTextAsPaths takes care of perspective transforms. |
| SkASSERT(!fGlyphTransform.hasPerspective()); |
| if (fNeedsDeviceSpaceGlyphs) { |
| fPaint.localCoordChangeInverse(fGlyphTransform); |
| fContext->setIdentityMatrix(); |
| } |
| } |
| |
| fStroke = SkStrokeRec(fSkPaint); |
| |
| if (fNeedsDeviceSpaceGlyphs) { |
| // The whole shape is baked into the glyph. Make NVPR just fill the |
| // baked shape. |
| fStroke.setStrokeStyle(-1, false); |
| } else { |
| if (fSkPaint.getStrokeWidth() == 0.0f) { |
| if (fSkPaint.getStyle() == SkPaint::kStrokeAndFill_Style) { |
| fStroke.setStrokeStyle(-1, false); |
| } else if (fSkPaint.getStyle() == SkPaint::kStroke_Style) { |
| // Approximate hairline stroke. |
| const SkMatrix& ctm = fContext->getMatrix(); |
| SkScalar strokeWidth = SK_Scalar1 / |
| (fTextRatio * SkVector::Make(ctm.getScaleX(), ctm.getSkewY()).length()); |
| fStroke.setStrokeStyle(strokeWidth, false); |
| } |
| } |
| |
| // Make glyph cache produce paths geometry for fill. We will stroke them |
| // by passing fStroke to drawPath. This is the fast path. |
| fSkPaint.setStyle(SkPaint::kFill_Style); |
| } |
| fStateRestore.set(fDrawTarget->drawState()); |
| |
| fDrawTarget->drawState()->setFromPaint(fPaint, fContext->getMatrix(), |
| fContext->getRenderTarget()); |
| |
| GR_STATIC_CONST_SAME_STENCIL(kStencilPass, |
| kZero_StencilOp, |
| kZero_StencilOp, |
| kNotEqual_StencilFunc, |
| 0xffff, |
| 0x0000, |
| 0xffff); |
| |
| *fDrawTarget->drawState()->stencil() = kStencilPass; |
| |
| size_t reserveAmount; |
| switch (skPaint.getTextEncoding()) { |
| default: |
| SkASSERT(false); |
| case SkPaint::kUTF8_TextEncoding: |
| reserveAmount = textByteLength; |
| break; |
| case SkPaint::kUTF16_TextEncoding: |
| reserveAmount = textByteLength / 2; |
| break; |
| case SkPaint::kUTF32_TextEncoding: |
| case SkPaint::kGlyphID_TextEncoding: |
| reserveAmount = textByteLength / 4; |
| break; |
| } |
| fPaths.setReserve(reserveAmount); |
| fTransforms.setReserve(reserveAmount); |
| } |
| |
| inline void GrStencilAndCoverTextContext::appendGlyph(GrGlyph::PackedID glyphID, |
| const SkPoint& pos, |
| GrTextStrike* strike, |
| GrFontScaler* scaler) { |
| GrGlyph* glyph = strike->getGlyph(glyphID, scaler); |
| if (NULL == glyph || glyph->fBounds.isEmpty()) { |
| return; |
| } |
| |
| if (scaler->getGlyphPath(glyph->glyphID(), &fTmpPath)) { |
| if (!fTmpPath.isEmpty()) { |
| *fPaths.append() = fContext->createPath(fTmpPath, fStroke); |
| SkMatrix* t = fTransforms.append(); |
| t->setTranslate(pos.fX, pos.fY); |
| t->preScale(fTextRatio, fTextRatio); |
| } |
| } |
| } |
| |
| void GrStencilAndCoverTextContext::finish() { |
| if (fPaths.count() > 0) { |
| fDrawTarget->drawPaths(static_cast<size_t>(fPaths.count()), |
| fPaths.begin(), fTransforms.begin(), |
| SkPath::kWinding_FillType, fStroke.getStyle()); |
| |
| for (int i = 0; i < fPaths.count(); ++i) { |
| fPaths[i]->unref(); |
| } |
| if (fPaths.count() > kMaxReservedGlyphs) { |
| fPaths.reset(); |
| fTransforms.reset(); |
| } else { |
| fPaths.rewind(); |
| fTransforms.rewind(); |
| } |
| } |
| fTmpPath.reset(); |
| |
| fDrawTarget->drawState()->stencil()->setDisabled(); |
| fStateRestore.set(NULL); |
| if (fNeedsDeviceSpaceGlyphs) { |
| fContext->setMatrix(fGlyphTransform); |
| } |
| GrTextContext::finish(); |
| } |
| |
