Exemplo n.º 1
0
void SkMultiPictureDraw::draw(bool flush) {
    AutoMPDReset mpdreset(this);

#ifdef FORCE_SINGLE_THREAD_DRAWING_FOR_TESTING
    for (int i = 0; i < fThreadSafeDrawData.count(); ++i) {
        fThreadSafeDrawData[i].draw();
    }
#else
    sk_parallel_for(fThreadSafeDrawData.count(), [&](int i) {
        fThreadSafeDrawData[i].draw();
    });
#endif

    // N.B. we could get going on any GPU work from this main thread while the CPU work runs.
    // But in practice, we've either got GPU work or CPU work, not both.

    const int count = fGPUDrawData.count();
    if (0 == count) {
        return;
    }

#if !defined(SK_IGNORE_GPU_LAYER_HOISTING) && SK_SUPPORT_GPU
    GrContext* context = fGPUDrawData[0].fCanvas->getGrContext();
    SkASSERT(context);

    // Start by collecting all the layers that are going to be atlased and render
    // them (if necessary). Hoisting the free floating layers is deferred until
    // drawing the canvas that requires them.
    SkTDArray<GrHoistedLayer> atlasedNeedRendering, atlasedRecycled;

    for (int i = 0; i < count; ++i) {
        const DrawData& data = fGPUDrawData[i];
        // we only expect 1 context for all the canvases
        SkASSERT(data.fCanvas->getGrContext() == context);

        if (!data.fPaint) {
            SkRect clipBounds;
            if (!data.fCanvas->getClipBounds(&clipBounds)) {
                continue;
            }

            SkMatrix initialMatrix = data.fCanvas->getTotalMatrix();
            initialMatrix.preConcat(data.fMatrix);

            GrRenderTarget* rt = data.fCanvas->internal_private_accessTopLayerRenderTarget();
            SkASSERT(rt);

            // TODO: sorting the cacheable layers from smallest to largest
            // would improve the packing and reduce the number of swaps
            // TODO: another optimization would be to make a first pass to
            // lock any required layer that is already in the atlas
            GrLayerHoister::FindLayersToAtlas(context, data.fPicture, initialMatrix,
                                              clipBounds,
                                              &atlasedNeedRendering, &atlasedRecycled,
                                              rt->numColorSamples());
        }
    }

    GrLayerHoister::DrawLayersToAtlas(context, atlasedNeedRendering);

    SkTDArray<GrHoistedLayer> needRendering, recycled;
#endif

    for (int i = 0; i < count; ++i) {
        const DrawData& data = fGPUDrawData[i];
        SkCanvas* canvas = data.fCanvas;
        const SkPicture* picture = data.fPicture;

#if !defined(SK_IGNORE_GPU_LAYER_HOISTING) && SK_SUPPORT_GPU
        if (!data.fPaint) {

            SkRect clipBounds;
            if (!canvas->getClipBounds(&clipBounds)) {
                continue;
            }

            SkAutoCanvasMatrixPaint acmp(canvas, &data.fMatrix, data.fPaint, picture->cullRect());

            const SkMatrix initialMatrix = canvas->getTotalMatrix();

            GrRenderTarget* rt = data.fCanvas->internal_private_accessTopLayerRenderTarget();
            SkASSERT(rt);

            // Find the layers required by this canvas. It will return atlased
            // layers in the 'recycled' list since they have already been drawn.
            GrLayerHoister::FindLayersToHoist(context, picture, initialMatrix,
                                              clipBounds, &needRendering, &recycled,
                                              rt->numColorSamples());

            GrLayerHoister::DrawLayers(context, needRendering);

            // Render the entire picture using new layers
            GrRecordReplaceDraw(picture, canvas, context->getLayerCache(),
                                initialMatrix, NULL);

            GrLayerHoister::UnlockLayers(context, needRendering);
            GrLayerHoister::UnlockLayers(context, recycled);

            needRendering.rewind();
            recycled.rewind();
        } else
#endif
        {
            canvas->drawPicture(picture, &data.fMatrix, data.fPaint);
        }
        if (flush) {
            canvas->flush();
        }
    }

#if !defined(SK_IGNORE_GPU_LAYER_HOISTING) && SK_SUPPORT_GPU
    GrLayerHoister::UnlockLayers(context, atlasedNeedRendering);
    GrLayerHoister::UnlockLayers(context, atlasedRecycled);
#if !GR_CACHE_HOISTED_LAYERS
    GrLayerHoister::PurgeCache(context);
#endif
#endif
}