Example #1
0
void Font::drawGlyphs(GraphicsContext* gc, const SimpleFontData* font,
                      const GlyphBuffer& glyphBuffer,  int from, int numGlyphs,
                      const FloatPoint& point) const {
    SkASSERT(sizeof(GlyphBufferGlyph) == sizeof(uint16_t)); // compile-time assert

    const GlyphBufferGlyph* glyphs = glyphBuffer.glyphs(from);
    SkScalar x = SkFloatToScalar(point.x());
    SkScalar y = SkFloatToScalar(point.y());

    // FIXME: text rendering speed:
    // Android has code in their WebCore fork to special case when the
    // GlyphBuffer has no advances other than the defaults. In that case the
    // text drawing can proceed faster. However, it's unclear when those
    // patches may be upstreamed to WebKit so we always use the slower path
    // here.
    const GlyphBufferAdvance* adv = glyphBuffer.advances(from);
    SkAutoSTMalloc<32, SkPoint> storage(numGlyphs), storage2(numGlyphs), storage3(numGlyphs);
    SkPoint* pos = storage.get();
    SkPoint* vPosBegin = storage2.get();
    SkPoint* vPosEnd = storage3.get();

    bool isVertical = font->platformData().orientation() == Vertical;
    for (int i = 0; i < numGlyphs; i++) {
        SkScalar myWidth = SkFloatToScalar(adv[i].width());
        pos[i].set(x, y);
        if (isVertical) {
            vPosBegin[i].set(x + myWidth, y);
            vPosEnd[i].set(x + myWidth, y - myWidth);
        }
        x += myWidth;
        y += SkFloatToScalar(adv[i].height());
    }

    PlatformContextSkia* platformContext = gc->platformContext();
    TextDrawingModeFlags textMode = gc->platformContext()->getTextDrawingMode();

    // We draw text up to two times (once for fill, once for stroke).
    if (textMode & TextModeFill) {
        SkPaint paint;
        gc->platformContext()->setupPaintForFilling(&paint);
        font->platformData().setupPaint(&paint);
        gc->platformContext()->adjustTextRenderMode(&paint);
        paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);

        if (isVertical) {
            SkPath path;
            for (int i = 0; i < numGlyphs; ++i) {
                path.reset();
                path.moveTo(vPosBegin[i]);
                path.lineTo(vPosEnd[i]);
                platformContext->drawTextOnPath(glyphs + i, 2, path, 0, paint);
            }
        } else
            platformContext->drawPosText(glyphs, numGlyphs << 1, pos, paint);
    }

    if ((textMode & TextModeStroke)
        && gc->platformContext()->getStrokeStyle() != NoStroke
        && gc->platformContext()->getStrokeThickness() > 0) {

        SkPaint paint;
        gc->platformContext()->setupPaintForStroking(&paint, 0, 0);
        font->platformData().setupPaint(&paint);
        gc->platformContext()->adjustTextRenderMode(&paint);
        paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);

        if (textMode & TextModeFill) {
            // If we also filled, we don't want to draw shadows twice.
            // See comment in FontChromiumWin.cpp::paintSkiaText() for more details.
            // Since we use the looper for shadows, we remove it (if any) now.
            paint.setLooper(0);
        }

        if (isVertical) {
            SkPath path;
            for (int i = 0; i < numGlyphs; ++i) {
                path.reset();
                path.moveTo(vPosBegin[i]);
                path.lineTo(vPosEnd[i]);
                platformContext->drawTextOnPath(glyphs + i, 2, path, 0, paint);
            }
        } else
            platformContext->drawPosText(glyphs, numGlyphs << 1, pos, paint);
    }
}