C++ SkPaint::measureText方法代码示例

//SAMSUNG_THAI_EDITING_FIX >>
FloatRect Font::selectionRectForComplexText(const TextRun& run,
                                const IntPoint& point, int h, int from, int to) const
{
    SkPaint              paint;
    SkPaint::FontMetrics metrics;
    float beforeWidth = 0.0f ;
    float afterWidth = 0.0f ;

    primaryFont()->platformData().setupPaint(&paint);

    size_t length = from ;
    if (length > 0) {
        beforeWidth = paint.measureText(run.characters(), length << 1);
    }

    length = to ;
    if (length > 0) {
        afterWidth = paint.measureText(run.characters(), length << 1);
    }

    
    return FloatRect(point.x() + floorf(beforeWidth),
                     point.y(),
                     roundf(afterWidth) - floorf(beforeWidth),
                     roundf(SkScalarToFloat(h)));
}

FloatRect Font::selectionRectForComplexText(const TextRun& run,
                                const IntPoint& point, int h, int from, int to) const
{
    SkPaint              paint;
    SkScalar             width, left;
    SkPaint::FontMetrics metrics;

    primaryFont()->platformData().setupPaint(&paint);

    SkScalar spacing = paint.getFontMetrics(&metrics);

    float beforeWidth = SkScalarToFloat(paint.measureText(run.characters(), from << 1));
    float afterWidth = SkScalarToFloat(paint.measureText(run.characters(), to << 1));

    if (run.rtl()) {
    	float totalWidth = SkScalarToFloat(paint.measureText(run.characters(), run.length() << 1));
    	return FloatRect(point.x() + floorf(totalWidth - afterWidth),
    	                 point.y(),
                         roundf(totalWidth - beforeWidth) - floorf(totalWidth - afterWidth),
    	                 //roundf(SkScalarToFloat(spacing))); // Don't compute rect height, but use h.
                         h);
    } else {
        return FloatRect(point.x() + floorf(beforeWidth),
                         point.y(),
                         roundf(afterWidth) - floorf(beforeWidth),
                         //roundf(SkScalarToFloat(spacing))); // Don't compute rect height, but use h.
                         h);
    }
}

void CommandSet::drawHelp(SkCanvas* canvas) {
    if (kNone_HelpMode == fHelpMode) {
        return;
    }

    // Sort commands for current mode:
    SkTQSort(fCommands.begin(), fCommands.end() - 1,
             kAlphabetical_HelpMode == fHelpMode ? compareCommandKey : compareCommandGroup);

    SkPaint bgPaint;
    bgPaint.setColor(0xC0000000);
    canvas->drawPaint(bgPaint);

    SkPaint paint;
    paint.setTextSize(16);
    paint.setAntiAlias(true);
    paint.setColor(0xFFFFFFFF);

    SkPaint groupPaint;
    groupPaint.setTextSize(18);
    groupPaint.setUnderlineText(true);
    groupPaint.setAntiAlias(true);
    groupPaint.setColor(0xFFFFFFFF);

    SkScalar x = SkIntToScalar(10);
    SkScalar y = SkIntToScalar(10);

    // Measure all key strings:
    SkScalar keyWidth = 0;
    for (Command& cmd : fCommands) {
        keyWidth = SkMaxScalar(keyWidth,
                               paint.measureText(cmd.fKeyName.c_str(), cmd.fKeyName.size()));
    }
    keyWidth += paint.measureText(" ", 1);

    // If we're grouping by category, we'll be adding text height on every new group (including the
    // first), so no need to do that here. Otherwise, skip down so the first line is where we want.
    if (kGrouped_HelpMode != fHelpMode) {
        y += paint.getTextSize();
    }

    // Print everything:
    SkString lastGroup;
    for (Command& cmd : fCommands) {
        if (kGrouped_HelpMode == fHelpMode && lastGroup != cmd.fGroup) {
            // Group change. Advance and print header:
            y += paint.getTextSize();
            canvas->drawText(cmd.fGroup.c_str(), cmd.fGroup.size(), x, y, groupPaint);
            y += groupPaint.getTextSize() + 2;
            lastGroup = cmd.fGroup;
        }

        canvas->drawText(cmd.fKeyName.c_str(), cmd.fKeyName.size(), x, y, paint);
        SkString text = SkStringPrintf(": %s", cmd.fDescription.c_str());
        canvas->drawText(text.c_str(), text.size(), x + keyWidth, y, paint);
        y += paint.getTextSize() + 2;
    }
}

    virtual void onDraw(SkCanvas* canvas) {
        SkPaint paint;
        SkScalar horizMargin = 10;
        SkScalar vertMargin = 10;

        SkBitmap src;
        src.allocN32Pixels(40, 40);
        SkCanvas canvasTmp(src);

        draw_checks(&canvasTmp, 40, 40);

        for (unsigned i = 0; i < NUM_CONFIGS; ++i) {
            src.copyTo(&fDst[i], gColorTypes[i]);
        }

        canvas->clear(0xFFDDDDDD);
        paint.setAntiAlias(true);
        sk_tool_utils::set_portable_typeface(&paint);
        
        SkScalar width = SkIntToScalar(40);
        SkScalar height = SkIntToScalar(40);
        if (paint.getFontSpacing() > height) {
            height = paint.getFontSpacing();
        }
        for (unsigned i = 0; i < NUM_CONFIGS; i++) {
            const char* name = gColorTypeNames[src.colorType()];
            SkScalar textWidth = paint.measureText(name, strlen(name));
            if (textWidth > width) {
                width = textWidth;
            }
        }
        SkScalar horizOffset = width + horizMargin;
        SkScalar vertOffset = height + vertMargin;
        canvas->translate(SkIntToScalar(20), SkIntToScalar(20));

        for (unsigned i = 0; i < NUM_CONFIGS; i++) {
            canvas->save();
            // Draw destination config name
            const char* name = gColorTypeNames[fDst[i].colorType()];
            SkScalar textWidth = paint.measureText(name, strlen(name));
            SkScalar x = (width - textWidth) / SkScalar(2);
            SkScalar y = paint.getFontSpacing() / SkScalar(2);
            canvas->drawText(name, strlen(name), x, y, paint);

            // Draw destination bitmap
            canvas->translate(0, vertOffset);
            x = (width - 40) / SkScalar(2);
            canvas->drawBitmap(fDst[i], x, 0, &paint);
            canvas->restore();

            canvas->translate(horizOffset, 0);
        }
    }

    virtual void onDraw(SkCanvas* canvas) {
        SkPaint paint;
        SkScalar horizMargin(SkIntToScalar(10));
        SkScalar vertMargin(SkIntToScalar(10));

        SkBitmapDevice devTmp(SkBitmap::kARGB_8888_Config, 40, 40, false);
        SkCanvas canvasTmp(&devTmp);

        draw_checks(&canvasTmp, 40, 40);
        SkBitmap src = canvasTmp.getTopDevice()->accessBitmap(false);

        for (unsigned i = 0; i < NUM_CONFIGS; ++i) {
            if (!src.deepCopyTo(&fDst[i], gConfigs[i])) {
                src.copyTo(&fDst[i], gConfigs[i]);
            }
        }

        canvas->clear(0xFFDDDDDD);
        paint.setAntiAlias(true);
        SkScalar width = SkIntToScalar(40);
        SkScalar height = SkIntToScalar(40);
        if (paint.getFontSpacing() > height) {
            height = paint.getFontSpacing();
        }
        for (unsigned i = 0; i < NUM_CONFIGS; i++) {
            const char* name = gConfigNames[src.config()];
            SkScalar textWidth = paint.measureText(name, strlen(name));
            if (textWidth > width) {
                width = textWidth;
            }
        }
        SkScalar horizOffset = width + horizMargin;
        SkScalar vertOffset = height + vertMargin;
        canvas->translate(SkIntToScalar(20), SkIntToScalar(20));

        for (unsigned i = 0; i < NUM_CONFIGS; i++) {
            canvas->save();
            // Draw destination config name
            const char* name = gConfigNames[fDst[i].config()];
            SkScalar textWidth = paint.measureText(name, strlen(name));
            SkScalar x = (width - textWidth) / SkScalar(2);
            SkScalar y = paint.getFontSpacing() / SkScalar(2);
            canvas->drawText(name, strlen(name), x, y, paint);

            // Draw destination bitmap
            canvas->translate(0, vertOffset);
            x = (width - 40) / SkScalar(2);
            canvas->drawBitmap(fDst[i], x, 0, &paint);
            canvas->restore();

            canvas->translate(horizOffset, 0);
        }
    }

static void test_text(SkCanvas* canvas) {
    SkPaint paint;
    paint.setAntiAlias(true);
    paint.setTextSize(20);

    const char* str = "Hamburgefons";
    size_t len = strlen(str);
    SkScalar x = 20;
    SkScalar y = 20;

    canvas->drawText(str, len, x, y, paint);

    y += 20;

    const SkPoint pts[] = { { x, y }, { x + paint.measureText(str, len), y } };
    const SkColor colors[] = { SK_ColorBLACK, SK_ColorBLACK, 0 };
    const SkScalar pos[] = { 0, 0.9f, 1 };
    SkShader* s = SkGradientShader::CreateLinear(pts, colors, pos,
                                                 SK_ARRAY_COUNT(colors),
                                                 SkShader::kClamp_TileMode);
    paint.setShader(s)->unref();
    canvas->drawText(str, len, x, y, paint);

    y += 20;
    paint.setShader(NULL);
    drawFadingText(canvas, str, len, x, y, paint);
}

    void recordCanvas(SkCanvas* canvas) override {
        SkPaint paint;
        paint.setTextSize(fTextSize);
        paint.setColor(SK_ColorBLACK);

        const char* text = "Hamburgefons";
        size_t len = strlen(text);
        const SkScalar textWidth = paint.measureText(text, len);

        SkScalar* adv = new SkScalar[len];
        paint.getTextWidths(text, len, adv);

        for (SkScalar x = 0; x < fPictureWidth; x += textWidth) {
            for (SkScalar y = 0; y < fPictureHeight; y += fTextSize) {

                SkPoint* pos = new SkPoint[len];
                SkScalar advX = 0;

                for (size_t i = 0; i < len; i++) {
                    if (fDrawPosH)
                        pos[i].set(x + advX, y);
                    else
                        pos[i].set(x + advX, y + i);
                    advX += adv[i];
                }

                canvas->drawPosText(text, len, pos, paint);
                delete[] pos;
            }
        }
        delete[] adv;
    }

    void onDraw(SkCanvas* canvas) override {
        SkPaint paint;
        paint.setAntiAlias(true);
        paint.setLCDRenderText(true);
        paint.setSubpixelText(true);
        paint.setTypeface(fTypefaces[0]);
        paint.setTextSize(192);

        // Make sure the nul character does not cause problems.
        paint.measureText("\0", 1);

        SkScalar x = 20;
        SkScalar y = 128;
        SkString text("ABCDEFGHIJ");
        draw_string(canvas, text, x, y, paint);
        y += 100;
        SkString text2("KLMNOPQRS");
        draw_string(canvas, text2, x, y, paint);
        y += 100;
        SkString text3("TUVWXYZ012");
        draw_string(canvas, text3, x, y, paint);
        y += 100;
        paint.setTypeface(fTypefaces[1]);
        draw_string(canvas, text, x, y, paint);
        y += 100;
        draw_string(canvas, text2, x, y, paint);
        y += 100;
        draw_string(canvas, text3, x, y, paint);
        y += 100;
    }

    static void drawBaseline(SkCanvas* canvas, const SkPaint& paint,
                             SkScalar x, SkScalar y) {
        SkScalar total = paint.measureText(gText, gLen);

        SkPaint p;
        p.setAntiAlias(true);
        p.setColor(0x80FF0000);
        canvas->drawLine(x, y,
                         paint.isVerticalText() ? x : x + total,
                         paint.isVerticalText() ? y + total : y,
                         p);

        p.setColor(0xFF0000FF);
        SkScalar adv[gLen];
        int numChars = paint.getTextWidths(gText, gLen, adv, nullptr);
        for (int i = 0; i < numChars; ++i) {
            canvas->drawCircle(x, y, SK_Scalar1 * 3 / 2, p);
            if (paint.isVerticalText()) {
                y += adv[i];
            } else {
                x += adv[i];
            }
        }
        canvas->drawCircle(x, y, SK_Scalar1 * 3 / 2, p);
    }

	bool draw(SkCanvas* canvas, const SkString& newText, SkScalar x, SkScalar y, SkPaint& paint)
	{
		SkScalar scale;

		if (fInterp.timeToValues(SkTime::GetMSecs(), &scale) == SkInterpolator::kFreezeEnd_Result)
		{
			canvas->drawText(newText.c_str(), newText.size(), x, y, paint);
			return false;
		}
		else
		{
			U8 alpha = paint.getAlpha();
			SkScalar above, below;
			(void)paint.measureText(nil, 0, &above, &below);
			SkScalar height = below - above;
			SkScalar dy = SkScalarMul(height, scale);
			if (scale < 0)
				height = -height;

			// draw the old
			paint.setAlpha((U8)SkScalarMul(alpha, SK_Scalar1 - SkScalarAbs(scale)));
			canvas->drawText(fOldText.c_str(), fOldText.size(), x, y - dy, paint);
			// draw the new
			paint.setAlpha((U8)SkScalarMul(alpha, SkScalarAbs(scale)));
			canvas->drawText(newText.c_str(), newText.size(), x, y + height - dy, paint);
			// restore the paint
			paint.setAlpha(alpha);
			return true;
		}
	}

static void test_breakText() {
    SkPaint paint;
    const char* text = "sdfkljAKLDFJKEWkldfjlk#$%&sdfs.dsj";
    size_t length = strlen(text);
    SkScalar width = paint.measureText(text, length);

    SkScalar mm = 0;
    SkScalar nn = 0;
    for (SkScalar w = 0; w <= width; w += SK_Scalar1) {
        SkScalar m;
        size_t n = paint.breakText(text, length, w, &m,
                                    SkPaint::kBackward_TextBufferDirection);

        SkASSERT(n <= length);
        SkASSERT(m <= width);

        if (n == 0) {
            SkASSERT(m == 0);
        } else {
            // now assert that we're monotonic
            if (n == nn) {
                SkASSERT(m == mm);
            } else {
                SkASSERT(n > nn);
                SkASSERT(m > mm);
            }
        }
        nn = SkIntToScalar(n);
        mm = m;
    }

    SkDEBUGCODE(size_t length2 =) paint.breakText(text, length, width, &mm);
    SkASSERT(length2 == length);
    SkASSERT(mm == width);
}

const SkAdvancedTypefaceMetrics* SkPDFFont::GetMetrics(SkTypeface* typeface,
                                                       SkPDFCanon* canon) {
    SkASSERT(typeface);
    SkFontID id = typeface->uniqueID();
    if (std::unique_ptr<SkAdvancedTypefaceMetrics>* ptr = canon->fTypefaceMetrics.find(id)) {
        return ptr->get();  // canon retains ownership.
    }
    int count = typeface->countGlyphs();
    if (count <= 0 || count > 1 + SK_MaxU16) {
        // Cache nullptr to skip this check.  Use SkSafeUnref().
        canon->fTypefaceMetrics.set(id, nullptr);
        return nullptr;
    }
    std::unique_ptr<SkAdvancedTypefaceMetrics> metrics = typeface->getAdvancedMetrics();
    if (!metrics) {
        metrics = skstd::make_unique<SkAdvancedTypefaceMetrics>();
    }

    if (0 == metrics->fStemV || 0 == metrics->fCapHeight) {
        SkPaint tmpPaint;
        tmpPaint.setHinting(SkPaint::kNo_Hinting);
        tmpPaint.setTypeface(sk_ref_sp(typeface));
        tmpPaint.setTextSize(1000);  // glyph coordinate system
        if (0 == metrics->fStemV) {
            // Figure out a good guess for StemV - Min width of i, I, !, 1.
            // This probably isn't very good with an italic font.
            int16_t stemV = SHRT_MAX;
            for (char c : {'i', 'I', '!', '1'}) {
                SkRect bounds;
                tmpPaint.measureText(&c, 1, &bounds);
                stemV = SkTMin(stemV, SkToS16(SkScalarRoundToInt(bounds.width())));
            }
            metrics->fStemV = stemV;
        }
        if (0 == metrics->fCapHeight) {
            // Figure out a good guess for CapHeight: average the height of M and X.
            SkScalar capHeight = 0;
            for (char c : {'M', 'X'}) {
                SkRect bounds;
                tmpPaint.measureText(&c, 1, &bounds);
                capHeight += bounds.height();
            }
            metrics->fCapHeight = SkToS16(SkScalarRoundToInt(capHeight / 2));
        }
    }
    return canon->fTypefaceMetrics.set(id, std::move(metrics))->get();
}

static void thread_main(void*) {
    SkGraphics::SetTLSFontCacheLimit(1 * 1024 * 1024);

    const char text[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
    size_t len = strlen(text);

    SkPaint paint;

    for (int j = 0; j < 10; ++j) {
        for (int i = 9; i <= 48; ++i) {
            paint.setTextSize(SkIntToScalar(i));
            paint.setAntiAlias(false);
            paint.measureText(text, len);
            paint.setAntiAlias(true);
            paint.measureText(text, len);
        }
    }
}

static void draw_label(SkCanvas* canvas, const char* label,
                       const SkPoint& offset) {
    SkPaint paint;
    size_t len = strlen(label);

    SkScalar width = paint.measureText(label, len);
    canvas->drawText(label, len, offset.x() - width / 2, offset.y(),
                     paint);
}

static void drawTestCase(SkCanvas* canvas,
                         SkScalar textScale,
                         SkScalar strokeWidth,
                         SkPaint::Style strokeStyle) {
        SkPaint paint;
        paint.setColor(SK_ColorBLACK);
        paint.setAntiAlias(true);
        paint.setTextSize(kTextHeight * textScale);
        sk_tool_utils::set_portable_typeface(&paint);
        paint.setStrokeWidth(strokeWidth);
        paint.setStyle(strokeStyle);

        // This demonstrates that we can not measure the text if
        // there's a device transform. The canvas total matrix will
        // end up being a device transform.
        bool drawRef = !(canvas->getTotalMatrix().getType() &
                         ~(SkMatrix::kIdentity_Mask | SkMatrix::kTranslate_Mask));

        SkRect bounds;
        if (drawRef) {
            SkScalar advance = paint.measureText(kText, sizeof(kText) - 1, &bounds);

            paint.setStrokeWidth(0.0f);
            paint.setStyle(SkPaint::kStroke_Style);

            // Green box is the measured text bounds.
            paint.setColor(SK_ColorGREEN);
            canvas->drawRect(bounds, paint);

            // Red line is the measured advance from the 0,0 of the text position.
            paint.setColor(SK_ColorRED);
            canvas->drawLine(0.0f, 0.0f, advance, 0.0f, paint);
        }

        // Black text is the testcase, eg. the text.
        paint.setColor(SK_ColorBLACK);
        paint.setStrokeWidth(strokeWidth);
        paint.setStyle(strokeStyle);
        canvas->drawText(kText, sizeof(kText) - 1, 0.0f, 0.0f, paint);

        if (drawRef) {
            SkScalar widths[sizeof(kText) - 1];
            paint.getTextWidths(kText, sizeof(kText) - 1, widths, nullptr);

            paint.setStrokeWidth(0.0f);
            paint.setStyle(SkPaint::kStroke_Style);

            // Magenta lines are the positions for the characters.
            paint.setColor(SK_ColorMAGENTA);
            SkScalar w = bounds.x();
            for (size_t i = 0; i < sizeof(kText) - 1; ++i) {
                canvas->drawLine(w, 0.0f, w, 5.0f, paint);
                w += widths[i];
            }
        }
}