C++ SkPaint::getTextPath方法代码示例

void draw(SkCanvas* canvas) {
    SkPaint paint;
    paint.setTextSize(128);
    SkPath path, path2;
    paint.getTextPath("A", 1, 60, 100, &path);
    paint.getTextPath("Z", 1, 60, 100, &path2);
    SkPoint pt, pt2;
    path.getLastPt(&pt);
    path2.getLastPt(&pt2);
    path.setLastPt(pt2);
    path2.setLastPt(pt);
    canvas->drawPath(path, paint);
    canvas->drawPath(path2, paint);
}

static void lettersToBitmap2(SkBitmap* dst, const char chars[],
                            const SkPaint& original, SkBitmap::Config config) {
    SkPath path;
    SkScalar x = 0;
    SkScalar width;
    SkPath p;
    for (size_t i = 0; i < strlen(chars); i++) {
        original.getTextPath(&chars[i], 1, x, 0, &p);
        path.addPath(p);
        original.getTextWidths(&chars[i], 1, &width);
        x += width;
    }
    SkRect bounds = path.getBounds();
    SkScalar sw = -original.getStrokeWidth();
    bounds.inset(sw, sw);
    path.offset(-bounds.fLeft, -bounds.fTop);
    bounds.offset(-bounds.fLeft, -bounds.fTop);

    int w = SkScalarRound(bounds.width());
    int h = SkScalarRound(bounds.height());
    SkPaint paint(original);

    paint.setAntiAlias(true);
    paint.setXfermodeMode(SkXfermode::kDstATop_Mode);
    paint.setColor(original.getColor());
    paint.setStyle(SkPaint::kStroke_Style);

    dst->setConfig(config, w, h);
    dst->allocPixels();
    dst->eraseColor(SK_ColorWHITE);

    SkCanvas canvas(*dst);
    canvas.drawPath(path, paint);
}

    virtual void onDraw(SkCanvas* canvas) {
        // explicitly add spaces, to test a prev. bug
        const char* text = "Ham bur ge fons";
        int len = SkToInt(strlen(text));
        SkPath path;

        SkPaint paint;
        paint.setAntiAlias(true);
        paint.setTextSize(SkIntToScalar(48));

        canvas->translate(SkIntToScalar(10), SkIntToScalar(64));

        canvas->drawText(text, len, 0, 0, paint);
        paint.getTextPath(text, len, 0, 0, &path);
        strokePath(canvas, path);
        path.reset();

        SkAutoTArray<SkPoint>  pos(len);
        SkAutoTArray<SkScalar> widths(len);
        paint.getTextWidths(text, len, &widths[0]);

        SkLCGRandom rand;
        SkScalar x = SkIntToScalar(20);
        SkScalar y = SkIntToScalar(100);
        for (int i = 0; i < len; ++i) {
            pos[i].set(x, y + rand.nextSScalar1() * 24);
            x += widths[i];
        }

        canvas->translate(0, SkIntToScalar(64));

        canvas->drawPosText(text, len, &pos[0], paint);
        paint.getPosTextPath(text, len, &pos[0], &path);
        strokePath(canvas, path);
    }

    virtual void onDraw(SkCanvas* canvas) {
        if (false) test_rev(canvas); // avoid bit rot, suppress warning
        SkRect r = { 10, 10, 100, 60 };

        SkPath path;

        path.addRect(r); test_rev(canvas, path);

        canvas->translate(0, 100);
        path.offset(20, 20);
        path.addRect(r); test_rev(canvas, path);

        canvas->translate(0, 100);
        path.reset();
        path.moveTo(10, 10); path.lineTo(30, 30);
        path.addOval(r);
        r.offset(50, 20);
        path.addOval(r);
        test_rev(canvas, path);

        SkPaint paint;
        paint.setTextSize(SkIntToScalar(100));
        SkTypeface* hira = SkTypeface::CreateFromName("Hiragino Maru Gothic Pro", SkTypeface::kNormal);
        SkSafeUnref(paint.setTypeface(hira));
        path.reset();
        paint.getTextPath("e", 1, 50, 50, &path);
        canvas->translate(0, 100);
        test_rev(canvas, path);
    }

static HB_Error getOutlinePoint(HB_Font hbFont, HB_Glyph glyph, int flags,
                                hb_uint32 index, HB_Fixed* xPos, HB_Fixed* yPos,
                                hb_uint32* resultingNumPoints) {
    SkHarfBuzzFont* font = reinterpret_cast<SkHarfBuzzFont*>(hbFont->userData);
    SkPaint paint;

    font->setupPaint(&paint);
    paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
    if (flags & HB_ShaperFlag_UseDesignMetrics) {
        paint.setHinting(SkPaint::kNo_Hinting);
    }

    SkPath path;
    uint16_t glyph16 = SkToU16(glyph);
    paint.getTextPath(&glyph16, sizeof(glyph16), 0, 0, &path);
    int numPoints = path.countPoints();
    if (index >= numPoints) {
        return HB_Err_Invalid_SubTable;
    }

    SkPoint pt = path.getPoint(index);
    *xPos = SkScalarToHarfbuzzFixed(pt.fX);
    *yPos = SkScalarToHarfbuzzFixed(pt.fY);
    *resultingNumPoints = numPoints;

    return HB_Err_Ok;
}

static HB_Error getOutlinePoint(HB_Font hbFont, HB_Glyph glyph, int flags, hb_uint32 point, HB_Fixed* xPos, HB_Fixed* yPos, hb_uint32* resultingNumPoints)
{
    FontPlatformData* font = reinterpret_cast<FontPlatformData*>(hbFont->userData);
    SkPaint paint;

    if (flags & HB_ShaperFlag_UseDesignMetrics)
        return HB_Err_Invalid_Argument;  // This is requesting pre-hinted positions. We can't support this.

    font->setupPaint(&paint);
    paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
    uint16_t glyph16 = glyph;
    SkPath path;
    paint.getTextPath(&glyph16, sizeof(glyph16), 0, 0, &path);
    int numPoints = path.getPoints(0, 0);
    if (point >= static_cast<unsigned>(numPoints))
        return HB_Err_Invalid_SubTable;
    SkPoint* points = reinterpret_cast<SkPoint*>(fastMalloc(sizeof(SkPoint) * (point + 1)));
    if (!points)
        return HB_Err_Invalid_SubTable;
    // Skia does let us get a single point from the path.
    path.getPoints(points, point + 1);
    *xPos = SkiaScalarToHarfbuzzFixed(points[point].fX);
    *yPos = SkiaScalarToHarfbuzzFixed(points[point].fY);
    *resultingNumPoints = numPoints;
    fastFree(points);

    return HB_Err_Ok;
}

static HB_Error getOutlinePoint(HB_Font hbFont, HB_Glyph glyph, int flags, hb_uint32 point,
        HB_Fixed* xPos, HB_Fixed* yPos, hb_uint32* resultingNumPoints)
{
    if (flags & HB_ShaperFlag_UseDesignMetrics)
        // This is requesting pre-hinted positions. We can't support this.
        return HB_Err_Invalid_Argument;

    SkPaint* paint = static_cast<SkPaint*>(hbFont->userData);
    paint->setTextEncoding(SkPaint::kGlyphID_TextEncoding);

    uint16_t glyph16 = glyph;
    SkPath path;
    paint->getTextPath(&glyph16, sizeof(glyph16), 0, 0, &path);
    uint32_t numPoints = path.getPoints(0, 0);
    if (point >= numPoints)
        return HB_Err_Invalid_SubTable;
    SkPoint* points = static_cast<SkPoint*>(malloc(sizeof(SkPoint) * (point + 1)));
    if (!points)
        return HB_Err_Invalid_SubTable;
    // Skia does let us get a single point from the path.
    path.getPoints(points, point + 1);
    *xPos = SkScalarToHBFixed(points[point].fX);
    *yPos = SkScalarToHBFixed(points[point].fY);
    *resultingNumPoints = numPoints;
    delete points;

    return HB_Err_Ok;
}

void SkTextToPath::onEndElement(SkAnimateMaker& maker) {
    if (paint == NULL || path == NULL || text == NULL) {
        // !!! add error message here
        maker.setErrorCode(SkDisplayXMLParserError::kErrorInAttributeValue);
        return;
    }
    SkPaint realPaint;
    paint->setupPaint(&realPaint);
    realPaint.getTextPath(text->getText(), text->getSize(), text->x, 
        text->y, &path->getPath());
}

void draw(SkCanvas* canvas) {
    SkPaint paint;
    paint.setTextSize(80);
    SkPath path, path2;
    paint.getTextPath("ABC", 3, 20, 80, &path);
    path.offset(20, 20, &path2);
    Op(path, path2, SkPathOp::kDifference_SkPathOp, &path);
    path.addPath(path2);
    paint.setStyle(SkPaint::kStroke_Style);
    canvas->drawPath(path, paint);
}

    static void drawdots(SkCanvas* canvas, const SkPaint& orig) {
        SkTDArray<SkPoint> pts;
        SkPathEffect* pe = makepe(0, &pts);

        SkScalar width = -1;
        SkPath path, dstPath;
        orig.getTextPath("9", 1, 0, 0, &path);
        pe->filterPath(&dstPath, path, &width);

        SkPaint p;
        p.setAntiAlias(true);
        p.setStrokeWidth(10);
        p.setColor(SK_ColorRED);
        canvas->drawPoints(SkCanvas::kPoints_PointMode, pts.count(), pts.begin(),
                           p);
    }

void draw(SkCanvas* canvas) {
    SkPaint paint;
    paint.setAntiAlias(true);
    paint.setTextSize(256);
    SkPath asterisk, path;
    paint.getTextPath("*", 1, 50, 192, &asterisk);
    SkPath::Iter iter(asterisk, true);
    SkPoint start[4], pts[4];
    iter.next(start);  // skip moveTo
    iter.next(start);  // first quadTo
    path.moveTo((start[0] + start[1]) * 0.5f);
    while (SkPath::kClose_Verb != iter.next(pts)) {
        path.quadTo(pts[0], (pts[0] + pts[1]) * 0.5f);
    }
    path.quadTo(start[0], (start[0] + start[1]) * 0.5f);
    canvas->drawPath(path, paint);
}

static void output_path_data(const SkPaint& paint, const char* used,
        int emSize, SkString* ptsOut, SkTDArray<SkPath::Verb>* verbs,
        SkTDArray<unsigned>* charCodes, SkTDArray<SkScalar>* widths) {
   while (*used) {
        SkUnichar index = SkUTF8_NextUnichar(&used);
        SkPath path;
        paint.getTextPath((const void*) &index, 2, 0, 0, &path);
        SkPath::RawIter iter(path);
        SkPath::Verb verb;
        SkPoint pts[4];
        while ((verb = iter.next(pts)) != SkPath::kDone_Verb) {
            *verbs->append() = verb;
            switch (verb) {
                case SkPath::kMove_Verb:
                    output_points(&pts[0], emSize, 1, ptsOut);
                    break;
                case SkPath::kLine_Verb:
                    output_points(&pts[1], emSize, 1, ptsOut);
                    break;
                case SkPath::kQuad_Verb:
                    output_points(&pts[1], emSize, 2, ptsOut);
                    break;
                case SkPath::kCubic_Verb:
                    output_points(&pts[1], emSize, 3, ptsOut);
                    break;
                case SkPath::kClose_Verb:
                    break;
                default:
                    SkDEBUGFAIL("bad verb");
                    SkASSERT(0);
            }
        }
        *verbs->append() = SkPath::kDone_Verb;
        *charCodes->append() = index;
        SkScalar width;
        SkDEBUGCODE(int charCount =) paint.getTextWidths((const void*) &index, 2, &width);
        SkASSERT(charCount == 1);
//        SkASSERT(floor(width) == width);  // not true for Hiragino Maru Gothic Pro
        *widths->append() = width;
    }
}

static void draw_vector_logo(SkCanvas* canvas, const SkRect& viewBox) {
    constexpr char kSkiaStr[] = "SKIA";
    constexpr SkScalar kGradientPad = .1f;
    constexpr SkScalar kVerticalSpacing = 0.25f;
    constexpr SkScalar kAccentScale = 1.20f;

    SkPaint paint;
    paint.setAntiAlias(true);
    paint.setSubpixelText(true);
    paint.setFakeBoldText(true);
    sk_tool_utils::set_portable_typeface(&paint);

    SkPath path;
    SkRect iBox, skiBox, skiaBox;
    paint.getTextPath("SKI", 3, 0, 0, &path);
    TightBounds(path, &skiBox);
    paint.getTextPath("I", 1, 0, 0, &path);
    TightBounds(path, &iBox);
    iBox.offsetTo(skiBox.fRight - iBox.width(), iBox.fTop);

    const size_t textLen = strlen(kSkiaStr);
    paint.getTextPath(kSkiaStr, textLen, 0, 0, &path);
    TightBounds(path, &skiaBox);
    skiaBox.outset(0, 2 * iBox.width() * (kVerticalSpacing + 1));

    const SkScalar accentSize = iBox.width() * kAccentScale;
    const SkScalar underlineY = iBox.bottom() +
        (kVerticalSpacing + SkScalarSqrt(3) / 2) * accentSize;
    SkMatrix m;
    m.setRectToRect(skiaBox, viewBox, SkMatrix::kFill_ScaleToFit);
    SkAutoCanvasRestore acr(canvas, true);
    canvas->concat(m);

    canvas->drawCircle(iBox.centerX(),
                       iBox.y() - (0.5f + kVerticalSpacing) * accentSize,
                       accentSize / 2,
                       paint);

    path.reset();
    path.moveTo(iBox.centerX() - accentSize / 2, iBox.bottom() + kVerticalSpacing * accentSize);
    path.rLineTo(accentSize, 0);
    path.lineTo(iBox.centerX(), underlineY);
    canvas->drawPath(path, paint);

    SkRect underlineRect = SkRect::MakeLTRB(iBox.centerX() - iBox.width() * accentSize * 3,
                                            underlineY,
                                            iBox.centerX(),
                                            underlineY + accentSize / 10);
    const SkPoint pts1[] = { SkPoint::Make(underlineRect.x(), 0),
                             SkPoint::Make(iBox.centerX(), 0) };
    const SkScalar pos1[] = { 0, 0.75f };
    const SkColor colors1[] = { SK_ColorTRANSPARENT, SK_ColorBLACK };
    SkASSERT(SK_ARRAY_COUNT(pos1) == SK_ARRAY_COUNT(colors1));
    paint.setShader(SkGradientShader::MakeLinear(pts1, colors1, pos1, SK_ARRAY_COUNT(pos1),
                                                 SkShader::kClamp_TileMode));
    canvas->drawRect(underlineRect, paint);

    const SkPoint pts2[] = { SkPoint::Make(iBox.x() - iBox.width() * kGradientPad, 0),
                             SkPoint::Make(iBox.right() + iBox.width() * kGradientPad, 0) };
    const SkScalar pos2[] = { 0, .01f, 1.0f/3, 1.0f/3, 2.0f/3, 2.0f/3, .99f, 1 };
    const SkColor colors2[] = {
        SK_ColorBLACK,
        0xffca5139,
        0xffca5139,
        0xff8dbd53,
        0xff8dbd53,
        0xff5460a5,
        0xff5460a5,
        SK_ColorBLACK
    };
    SkASSERT(SK_ARRAY_COUNT(pos2) == SK_ARRAY_COUNT(colors2));
    paint.setShader(SkGradientShader::MakeLinear(pts2, colors2, pos2, SK_ARRAY_COUNT(pos2),
                                                 SkShader::kClamp_TileMode));
    canvas->drawText(kSkiaStr, textLen, 0, 0, paint);
}

    void onDrawContent(SkCanvas* canvas) override {
        SkPath path;
        SkScalar width = fWidth;

        if (fCubicButton.fEnabled) {
            path.moveTo(fPts[0]);
            path.cubicTo(fPts[1], fPts[2], fPts[3]);
            setForGeometry();
            draw_stroke(canvas, path, width, 950, false);
        }

        if (fConicButton.fEnabled) {
            path.moveTo(fPts[4]);
            path.conicTo(fPts[5], fPts[6], fWeight);
            setForGeometry();
            draw_stroke(canvas, path, width, 950, false);
        }

        if (fQuadButton.fEnabled) {
            path.reset();
            path.moveTo(fPts[7]);
            path.quadTo(fPts[8], fPts[9]);
            setForGeometry();
            draw_stroke(canvas, path, width, 950, false);
        }

        if (fRRectButton.fEnabled) {
            SkScalar rad = 32;
            SkRect r;
            r.set(&fPts[10], 2);
            path.reset();
            SkRRect rr;
            rr.setRectXY(r, rad, rad);
            path.addRRect(rr);
            setForGeometry();
            draw_stroke(canvas, path, width, 950, false);

            path.reset();
            SkRRect rr2;
            rr.inset(width/2, width/2, &rr2);
            path.addRRect(rr2, SkPath::kCCW_Direction);
            rr.inset(-width/2, -width/2, &rr2);
            path.addRRect(rr2, SkPath::kCW_Direction);
            SkPaint paint;
            paint.setAntiAlias(true);
            paint.setColor(0x40FF8844);
            canvas->drawPath(path, paint);
        }

        if (fCircleButton.fEnabled) {
            path.reset();
            SkRect r;
            r.set(&fPts[12], 2);
            path.addOval(r);
            setForGeometry();
            if (fCircleButton.fFill) {
                draw_fill(canvas, r, width);
            } else {
                draw_stroke(canvas, path, width, 950, false);
            }
        }

        if (fTextButton.fEnabled) {
            path.reset();
            SkPaint paint;
            paint.setAntiAlias(true);
            paint.setTextSize(fTextSize);
            paint.getTextPath(fText.c_str(), fText.size(), 0, fTextSize, &path);
            setForText();
            draw_stroke(canvas, path, width * fWidthScale / fTextSize, fTextSize, true);
        }

        if (fAnimate) {
            fWidth += fDWidth;
            if (fDWidth > 0 && fWidth > kWidthMax) {
                fDWidth = -fDWidth;
            } else if (fDWidth < 0 && fWidth < kWidthMin) {
                fDWidth = -fDWidth;
            }
        }
        setAsNeeded();
        if (fConicButton.fEnabled) {
            draw_control(canvas, fWeightControl, fWeight, 0, 5, "weight");
        }
#ifdef SK_DEBUG
        draw_control(canvas, fErrorControl, gDebugStrokerError, kStrokerErrorMin, kStrokerErrorMax,
                "error");
#endif
        draw_control(canvas, fWidthControl, fWidth * fWidthScale, kWidthMin * fWidthScale,
                kWidthMax * fWidthScale, "width");
        draw_button(canvas, fQuadButton);
        draw_button(canvas, fCubicButton);
        draw_button(canvas, fConicButton);
        draw_button(canvas, fRRectButton);
        draw_button(canvas, fCircleButton);
        draw_button(canvas, fTextButton);
        this->inval(NULL);
    }

static int count_char_points(const SkPaint& paint, char c) {
    SkPath  path;

    paint.getTextPath(&c, 1, 0, 0, &path);
    return path.getPoints(NULL, 0);
}