C++ SkPaint::getLooper方法代码示例

void paintSkiaText(GraphicsContext* context,
                   HFONT hfont,
                   int numGlyphs,
                   const WORD* glyphs,
                   const int* advances,
                   const GOFFSET* offsets,
                   const SkPoint* origin)
{
    HDC dc = GetDC(0);
    HGDIOBJ oldFont = SelectObject(dc, hfont);

    PlatformContextSkia* platformContext = context->platformContext();
    SkCanvas* canvas = platformContext->canvas();
    TextDrawingModeFlags textMode = platformContext->getTextDrawingMode();

    // If platformContext is GPU-backed make its GL context current.
    platformContext->makeGrContextCurrent();

    // Filling (if necessary). This is the common case.
    SkPaint paint;
    platformContext->setupPaintForFilling(&paint);
    paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
    setupPaintForFont(hfont, &paint, platformContext);

    bool didFill = false;

    if ((textMode & TextModeFill) && (SkColorGetA(paint.getColor()) || paint.getLooper())) {
        skiaDrawText(canvas, *origin, &paint, &glyphs[0], &advances[0], &offsets[0], numGlyphs);
        didFill = true;
    }

    // Stroking on top (if necessary).
    if ((textMode & TextModeStroke)
        && platformContext->getStrokeStyle() != NoStroke
        && platformContext->getStrokeThickness() > 0) {

        paint.reset();
        platformContext->setupPaintForStroking(&paint, 0, 0);
        paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
        setupPaintForFont(hfont, &paint, platformContext);

        if (didFill) {
            // If there is a shadow and we filled above, there will already be
            // a shadow. We don't want to draw it again or it will be too dark
            // and it will go on top of the fill.
            //
            // Note that this isn't strictly correct, since the stroke could be
            // very thick and the shadow wouldn't account for this. The "right"
            // thing would be to draw to a new layer and then draw that layer
            // with a shadow. But this is a lot of extra work for something
            // that isn't normally an issue.
            paint.setLooper(0);
        }

        skiaDrawText(canvas, *origin, &paint, &glyphs[0], &advances[0], &offsets[0], numGlyphs);
    }

    SelectObject(dc, oldFont);
    ReleaseDC(0, dc);
}

static bool fold_opacity_layer_color_to_paint(const SkPaint& layerPaint,
                                              bool isSaveLayer,
                                              SkPaint* paint) {
    // We assume layerPaint is always from a saveLayer.  If isSaveLayer is
    // true, we assume paint is too.

    // The alpha folding can proceed if the filter layer paint does not have properties which cause
    // the resulting filter layer to be "blended" in complex ways to the parent layer. For example,
    // looper drawing unmodulated filter layer twice and then modulating the result produces
    // different image to drawing modulated filter layer twice.
    // TODO: most likely the looper and only some xfer modes are the hard constraints
    if (paint->getXfermode() || paint->getLooper()) {
        return false;
    }

    if (!isSaveLayer && paint->getImageFilter()) {
        // For normal draws, the paint color is used as one input for the color for the draw. Image
        // filter will operate on the result, and thus we can not change the input.
        // For layer saves, the image filter is applied to the layer contents. The layer is then
        // modulated with the paint color, so it's fine to proceed with the fold for saveLayer
        // paints with image filters.
        return false;
    }

    if (paint->getColorFilter()) {
        // Filter input depends on the paint color.

        // Here we could filter the color if we knew the draw is going to be uniform color.  This
        // should be detectable as drawPath/drawRect/.. without a shader being uniform, while
        // drawBitmap/drawSprite or a shader being non-uniform. However, current matchers don't
        // give the type out easily, so just do not optimize that at the moment.
        return false;
    }

    const uint32_t layerColor = layerPaint.getColor();
    // The layer paint color must have only alpha component.
    if (SK_ColorTRANSPARENT != SkColorSetA(layerColor, SK_AlphaTRANSPARENT)) {
        return false;
    }

    // The layer paint can not have any effects.
    if (layerPaint.getPathEffect() ||
        layerPaint.getShader()      ||
        layerPaint.getXfermode()    ||
        layerPaint.getMaskFilter()  ||
        layerPaint.getColorFilter() ||
        layerPaint.getRasterizer()  ||
        layerPaint.getLooper()      ||
        layerPaint.getImageFilter()) {
        return false;
    }

    paint->setAlpha(SkMulDiv255Round(paint->getAlpha(), SkColorGetA(layerColor)));

    return true;
}

 static bool HasAnyEffect(const SkPaint& paint) {
     return paint.getPathEffect()  ||
            paint.getShader()      ||
            paint.getXfermode()    ||
            paint.getMaskFilter()  ||
            paint.getColorFilter() ||
            paint.getRasterizer()  ||
            paint.getLooper()      ||
            paint.getImageFilter();
 }

// Is the supplied paint simply a color?
static bool is_simple(const SkPaint& p) {
    return NULL == p.getPathEffect() &&
           NULL == p.getShader() &&
           NULL == p.getXfermode() &&
           NULL == p.getMaskFilter() &&
           NULL == p.getColorFilter() &&
           NULL == p.getRasterizer() &&
           NULL == p.getLooper() &&
           NULL == p.getImageFilter();
}

static void paintSkiaText(GraphicsContext* context, HFONT hfont,
                          SkTypeface* face, float size, uint32_t textFlags,
                          int numGlyphs,
                          const WORD* glyphs,
                          const int* advances,
                          const GOFFSET* offsets,
                          const SkPoint& origin,
                          const SkRect& textRect)
{
    TextDrawingModeFlags textMode = context->textDrawingMode();
    // Ensure font load for printing, because PDF device needs it.
    if (context->isPrintingDevice())
        FontPlatformData::ensureFontLoaded(hfont);

    // Filling (if necessary). This is the common case.
    SkPaint paint;
    context->setupPaintForFilling(&paint);
    paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
    setupPaintForFont(&paint, context, face, size, textFlags);

    bool didFill = false;

    if ((textMode & TextModeFill) && (SkColorGetA(paint.getColor()) || paint.getLooper())) {
        skiaDrawText(context, origin, textRect, &paint, &glyphs[0], &advances[0], &offsets[0], numGlyphs);
        didFill = true;
    }

    // Stroking on top (if necessary).
    if ((textMode & TextModeStroke)
        && context->strokeStyle() != NoStroke
        && context->strokeThickness() > 0) {

        paint.reset();
        context->setupPaintForStroking(&paint);
        paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
        setupPaintForFont(&paint, context, face, size, textFlags);

        if (didFill) {
            // If there is a shadow and we filled above, there will already be
            // a shadow. We don't want to draw it again or it will be too dark
            // and it will go on top of the fill.
            //
            // Note that this isn't strictly correct, since the stroke could be
            // very thick and the shadow wouldn't account for this. The "right"
            // thing would be to draw to a new layer and then draw that layer
            // with a shadow. But this is a lot of extra work for something
            // that isn't normally an issue.
            paint.setLooper(0);
        }

        skiaDrawText(context, origin, textRect, &paint, &glyphs[0], &advances[0], &offsets[0], numGlyphs);
    }
}

// Even with kEntirePaint_Bits, we always ensure that the master paint's
// text-encoding is respected, since that controls how we interpret the
// text/length parameters of a draw[Pos]Text call.
void SkLayerDrawLooper::ApplyInfo(SkPaint* dst, const SkPaint& src,
                                  const LayerInfo& info) {

    uint32_t mask = info.fFlagsMask;
    dst->setFlags((dst->getFlags() & ~mask) | (src.getFlags() & mask));
    dst->setColor(xferColor(src.getColor(), dst->getColor(), info.fColorMode));

    BitFlags bits = info.fPaintBits;
    SkPaint::TextEncoding encoding = dst->getTextEncoding();

    if (0 == bits) {
        return;
    }
    if (kEntirePaint_Bits == bits) {
        // we've already computed these, so save it from the assignment
        uint32_t f = dst->getFlags();
        SkColor c = dst->getColor();
        *dst = src;
        dst->setFlags(f);
        dst->setColor(c);
        dst->setTextEncoding(encoding);
        return;
    }

    if (bits & kStyle_Bit) {
        dst->setStyle(src.getStyle());
        dst->setStrokeWidth(src.getStrokeWidth());
        dst->setStrokeMiter(src.getStrokeMiter());
        dst->setStrokeCap(src.getStrokeCap());
        dst->setStrokeJoin(src.getStrokeJoin());
    }

    if (bits & kTextSkewX_Bit) {
        dst->setTextSkewX(src.getTextSkewX());
    }

    if (bits & kPathEffect_Bit) {
        dst->setPathEffect(src.getPathEffect());
    }
    if (bits & kMaskFilter_Bit) {
        dst->setMaskFilter(src.getMaskFilter());
    }
    if (bits & kShader_Bit) {
        dst->setShader(src.getShader());
    }
    if (bits & kColorFilter_Bit) {
        dst->setColorFilter(src.getColorFilter());
    }
    if (bits & kXfermode_Bit) {
        dst->setXfermode(src.getXfermode());
    }

    // we don't override these
#if 0
    dst->setTypeface(src.getTypeface());
    dst->setTextSize(src.getTextSize());
    dst->setTextScaleX(src.getTextScaleX());
    dst->setRasterizer(src.getRasterizer());
    dst->setLooper(src.getLooper());
    dst->setTextEncoding(src.getTextEncoding());
    dst->setHinting(src.getHinting());
#endif
}

// Even with kEntirePaint_Bits, we always ensure that the master paint's
// text-encoding is respected, since that controls how we interpret the
// text/length parameters of a draw[Pos]Text call.
void SkLayerDrawLooper::LayerDrawLooperContext::ApplyInfo(
        SkPaint* dst, const SkPaint& src, const LayerInfo& info) {
    SkColor4f srcColor = src.getColor4f();
#ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
    // The framework may respect the alpha value on the original paint.
    // Match this legacy behavior.
    if (src.getAlpha() == 255) {
        srcColor.fA = dst->getColor4f().fA;
    }
#endif
    dst->setColor4f(xferColor(srcColor, dst->getColor4f(), (SkBlendMode)info.fColorMode),
                    sk_srgb_singleton());

    BitFlags bits = info.fPaintBits;
    SkPaint::TextEncoding encoding = dst->getTextEncoding();

    if (0 == bits) {
        return;
    }
    if (kEntirePaint_Bits == bits) {
        // we've already computed these, so save it from the assignment
        uint32_t f = dst->getFlags();
        SkColor4f c = dst->getColor4f();
        *dst = src;
        dst->setFlags(f);
        dst->setColor4f(c, sk_srgb_singleton());
        dst->setTextEncoding(encoding);
        return;
    }

    if (bits & kStyle_Bit) {
        dst->setStyle(src.getStyle());
        dst->setStrokeWidth(src.getStrokeWidth());
        dst->setStrokeMiter(src.getStrokeMiter());
        dst->setStrokeCap(src.getStrokeCap());
        dst->setStrokeJoin(src.getStrokeJoin());
    }

    if (bits & kTextSkewX_Bit) {
        dst->setTextSkewX(src.getTextSkewX());
    }

    if (bits & kPathEffect_Bit) {
        dst->setPathEffect(src.refPathEffect());
    }
    if (bits & kMaskFilter_Bit) {
        dst->setMaskFilter(src.refMaskFilter());
    }
    if (bits & kShader_Bit) {
        dst->setShader(src.refShader());
    }
    if (bits & kColorFilter_Bit) {
        dst->setColorFilter(src.refColorFilter());
    }
    if (bits & kXfermode_Bit) {
        dst->setBlendMode(src.getBlendMode());
    }

    // we don't override these
#if 0
    dst->setTypeface(src.getTypeface());
    dst->setTextSize(src.getTextSize());
    dst->setTextScaleX(src.getTextScaleX());
    dst->setRasterizer(src.getRasterizer());
    dst->setLooper(src.getLooper());
    dst->setTextEncoding(src.getTextEncoding());
    dst->setHinting(src.getHinting());
#endif
}

void SkFlatPaint::dump() const {
    SkPaint defaultPaint;
    SkFlattenableReadBuffer buffer(fPaintData);
    SkTypeface* typeface = (SkTypeface*) buffer.readPtr();
    char pBuffer[DUMP_BUFFER_SIZE];
    char* bufferPtr = pBuffer;
    bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
        "paint: ");
    if (typeface != defaultPaint.getTypeface())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "typeface:%p ", typeface);
    SkScalar textSize = buffer.readScalar();
    if (textSize != defaultPaint.getTextSize())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "textSize:%g ", SkScalarToFloat(textSize));
    SkScalar textScaleX = buffer.readScalar();
    if (textScaleX != defaultPaint.getTextScaleX())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "textScaleX:%g ", SkScalarToFloat(textScaleX));
    SkScalar textSkewX = buffer.readScalar();
    if (textSkewX != defaultPaint.getTextSkewX())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "textSkewX:%g ", SkScalarToFloat(textSkewX));
    const SkPathEffect* pathEffect = (const SkPathEffect*) buffer.readFlattenable();
    if (pathEffect != defaultPaint.getPathEffect())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "pathEffect:%p ", pathEffect);
    SkDELETE(pathEffect);
    const SkShader* shader = (const SkShader*) buffer.readFlattenable();
    if (shader != defaultPaint.getShader())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "shader:%p ", shader);
    SkDELETE(shader);
    const SkXfermode* xfermode = (const SkXfermode*) buffer.readFlattenable();
    if (xfermode != defaultPaint.getXfermode())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "xfermode:%p ", xfermode);
    SkDELETE(xfermode);
    const SkMaskFilter* maskFilter = (const SkMaskFilter*) buffer.readFlattenable();
    if (maskFilter != defaultPaint.getMaskFilter())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "maskFilter:%p ", maskFilter);
    SkDELETE(maskFilter);
    const SkColorFilter* colorFilter = (const SkColorFilter*) buffer.readFlattenable();
    if (colorFilter != defaultPaint.getColorFilter())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "colorFilter:%p ", colorFilter);
    SkDELETE(colorFilter);
    const SkRasterizer* rasterizer = (const SkRasterizer*) buffer.readFlattenable();
    if (rasterizer != defaultPaint.getRasterizer())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "rasterizer:%p ", rasterizer);
    SkDELETE(rasterizer);
    const SkDrawLooper* drawLooper = (const SkDrawLooper*) buffer.readFlattenable();
    if (drawLooper != defaultPaint.getLooper())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "drawLooper:%p ", drawLooper);
    SkDELETE(drawLooper);
    unsigned color = buffer.readU32();
    if (color != defaultPaint.getColor())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "color:0x%x ", color);
    SkScalar strokeWidth = buffer.readScalar();
    if (strokeWidth != defaultPaint.getStrokeWidth())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "strokeWidth:%g ", SkScalarToFloat(strokeWidth));
    SkScalar strokeMiter = buffer.readScalar();
    if (strokeMiter != defaultPaint.getStrokeMiter())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "strokeMiter:%g ", SkScalarToFloat(strokeMiter));
    unsigned flags = buffer.readU16();
    if (flags != defaultPaint.getFlags())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "flags:0x%x ", flags);
    int align = buffer.readU8();
    if (align != defaultPaint.getTextAlign())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "align:0x%x ", align);
    int strokeCap = buffer.readU8();
    if (strokeCap != defaultPaint.getStrokeCap())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "strokeCap:0x%x ", strokeCap);
    int strokeJoin = buffer.readU8();
    if (strokeJoin != defaultPaint.getStrokeJoin())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "align:0x%x ", strokeJoin);
    int style = buffer.readU8();
    if (style != defaultPaint.getStyle())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "style:0x%x ", style);
    int textEncoding = buffer.readU8();
    if (textEncoding != defaultPaint.getTextEncoding())
        bufferPtr += snprintf(bufferPtr, DUMP_BUFFER_SIZE - (bufferPtr - pBuffer), 
            "textEncoding:0x%x ", textEncoding);
    SkDebugf("%s\n", pBuffer);
}