C++ LayerComposite::GetLayer方法代码示例

template<class ContainerT> void
ContainerRender(ContainerT* aContainer,
                LayerManagerComposite* aManager,
                const nsIntRect& aClipRect)
{
    /**
     * Setup our temporary surface for rendering the contents of this container.
     */
    RefPtr<CompositingRenderTarget> surface;

    Compositor* compositor = aManager->GetCompositor();

    RefPtr<CompositingRenderTarget> previousTarget = compositor->GetCurrentRenderTarget();

    nsIntRect visibleRect = aContainer->GetEffectiveVisibleRegion().GetBounds();

    aContainer->mSupportsComponentAlphaChildren = false;

    float opacity = aContainer->GetEffectiveOpacity();

    bool needsSurface = aContainer->UseIntermediateSurface();
    if (needsSurface) {
        SurfaceInitMode mode = INIT_MODE_CLEAR;
        bool surfaceCopyNeeded = false;
        gfx::IntRect surfaceRect = gfx::IntRect(visibleRect.x, visibleRect.y,
                                                visibleRect.width, visibleRect.height);
        gfx::IntPoint sourcePoint = gfx::IntPoint(visibleRect.x, visibleRect.y);
        // we're about to create a framebuffer backed by textures to use as an intermediate
        // surface. What to do if its size (as given by framebufferRect) would exceed the
        // maximum texture size supported by the GL? The present code chooses the compromise
        // of just clamping the framebuffer's size to the max supported size.
        // This gives us a lower resolution rendering of the intermediate surface (children layers).
        // See bug 827170 for a discussion.
        int32_t maxTextureSize = compositor->GetMaxTextureSize();
        surfaceRect.width = std::min(maxTextureSize, surfaceRect.width);
        surfaceRect.height = std::min(maxTextureSize, surfaceRect.height);
        if (aContainer->GetEffectiveVisibleRegion().GetNumRects() == 1 &&
                (aContainer->GetContentFlags() & Layer::CONTENT_OPAQUE))
        {
            // don't need a background, we're going to paint all opaque stuff
            aContainer->mSupportsComponentAlphaChildren = true;
            mode = INIT_MODE_NONE;
        } else {
            const gfx::Matrix4x4& transform3D = aContainer->GetEffectiveTransform();
            gfx::Matrix transform;
            // If we have an opaque ancestor layer, then we can be sure that
            // all the pixels we draw into are either opaque already or will be
            // covered by something opaque. Otherwise copying up the background is
            // not safe.
            if (HasOpaqueAncestorLayer(aContainer) &&
                    transform3D.Is2D(&transform) && !ThebesMatrix(transform).HasNonIntegerTranslation()) {
                surfaceCopyNeeded = gfxPlatform::ComponentAlphaEnabled();
                sourcePoint.x += transform._31;
                sourcePoint.y += transform._32;
                aContainer->mSupportsComponentAlphaChildren
                    = gfxPlatform::ComponentAlphaEnabled();
            }
        }

        sourcePoint -= compositor->GetCurrentRenderTarget()->GetOrigin();
        if (surfaceCopyNeeded) {
            surface = compositor->CreateRenderTargetFromSource(surfaceRect, previousTarget, sourcePoint);
        } else {
            surface = compositor->CreateRenderTarget(surfaceRect, mode);
        }

        if (!surface) {
            return;
        }

        compositor->SetRenderTarget(surface);
    } else {
        surface = previousTarget;
        aContainer->mSupportsComponentAlphaChildren = (aContainer->GetContentFlags() & Layer::CONTENT_OPAQUE) ||
                (aContainer->GetParent() && aContainer->GetParent()->SupportsComponentAlphaChildren());
    }

    nsAutoTArray<Layer*, 12> children;
    aContainer->SortChildrenBy3DZOrder(children);

    /**
     * Render this container's contents.
     */
    for (uint32_t i = 0; i < children.Length(); i++) {
        LayerComposite* layerToRender = static_cast<LayerComposite*>(children.ElementAt(i)->ImplData());

        if (layerToRender->GetLayer()->GetEffectiveVisibleRegion().IsEmpty() &&
                !layerToRender->GetLayer()->AsContainerLayer()) {
            continue;
        }

        if (i + 1 < children.Length() &&
                layerToRender->GetLayer()->GetEffectiveTransform().IsIdentity()) {
            LayerComposite* nextLayer = static_cast<LayerComposite*>(children.ElementAt(i + 1)->ImplData());
            nsIntRect nextLayerOpaqueRect;
            if (nextLayer && nextLayer->GetLayer()) {
                nextLayerOpaqueRect = GetOpaqueRect(nextLayer->GetLayer());
            }
            if (!nextLayerOpaqueRect.IsEmpty()) {
                nsIntRegion visibleRegion;
//.........这里部分代码省略.........

template<class ContainerT> void
ContainerRender(ContainerT* aContainer,
                const nsIntPoint& aOffset,
                LayerManagerComposite* aManager,
                const nsIntRect& aClipRect)
{
  /**
   * Setup our temporary surface for rendering the contents of this container.
   */
  RefPtr<CompositingRenderTarget> surface;

  Compositor* compositor = aManager->GetCompositor();

  RefPtr<CompositingRenderTarget> previousTarget = compositor->GetCurrentRenderTarget();

  nsIntPoint childOffset(aOffset);
  nsIntRect visibleRect = aContainer->GetEffectiveVisibleRegion().GetBounds();

  aContainer->mSupportsComponentAlphaChildren = false;

  float opacity = aContainer->GetEffectiveOpacity();

  bool needsSurface = aContainer->UseIntermediateSurface();
  if (needsSurface) {
    SurfaceInitMode mode = INIT_MODE_CLEAR;
    bool surfaceCopyNeeded = false;
    gfx::IntRect surfaceRect = gfx::IntRect(visibleRect.x, visibleRect.y,
                                            visibleRect.width, visibleRect.height);
    // we're about to create a framebuffer backed by textures to use as an intermediate
    // surface. What to do if its size (as given by framebufferRect) would exceed the
    // maximum texture size supported by the GL? The present code chooses the compromise
    // of just clamping the framebuffer's size to the max supported size.
    // This gives us a lower resolution rendering of the intermediate surface (children layers).
    // See bug 827170 for a discussion.
    int32_t maxTextureSize = compositor->GetMaxTextureSize();
    surfaceRect.width = std::min(maxTextureSize, surfaceRect.width);
    surfaceRect.height = std::min(maxTextureSize, surfaceRect.height);
    if (aContainer->GetEffectiveVisibleRegion().GetNumRects() == 1 &&
        (aContainer->GetContentFlags() & Layer::CONTENT_OPAQUE))
    {
      // don't need a background, we're going to paint all opaque stuff
      aContainer->mSupportsComponentAlphaChildren = true;
      mode = INIT_MODE_NONE;
    } else {
      const gfx3DMatrix& transform3D = aContainer->GetEffectiveTransform();
      gfxMatrix transform;
      // If we have an opaque ancestor layer, then we can be sure that
      // all the pixels we draw into are either opaque already or will be
      // covered by something opaque. Otherwise copying up the background is
      // not safe.
      if (HasOpaqueAncestorLayer(aContainer) &&
          transform3D.Is2D(&transform) && !transform.HasNonIntegerTranslation()) {
        mode = gfxPlatform::GetPlatform()->UsesSubpixelAATextRendering() ?
                                            INIT_MODE_COPY : INIT_MODE_CLEAR;
        surfaceCopyNeeded = (mode == INIT_MODE_COPY);
        surfaceRect.x += transform.x0;
        surfaceRect.y += transform.y0;
        aContainer->mSupportsComponentAlphaChildren
          = gfxPlatform::GetPlatform()->UsesSubpixelAATextRendering();
      }
    }

    surfaceRect -= gfx::IntPoint(aOffset.x, aOffset.y);
    if (surfaceCopyNeeded) {
      surface = compositor->CreateRenderTargetFromSource(surfaceRect, previousTarget);
    } else {
      surface = compositor->CreateRenderTarget(surfaceRect, mode);
    }
    compositor->SetRenderTarget(surface);
    childOffset.x = visibleRect.x;
    childOffset.y = visibleRect.y;
  } else {
    surface = previousTarget;
    aContainer->mSupportsComponentAlphaChildren = (aContainer->GetContentFlags() & Layer::CONTENT_OPAQUE) ||
      (aContainer->GetParent() && aContainer->GetParent()->SupportsComponentAlphaChildren());
  }

  nsAutoTArray<Layer*, 12> children;
  aContainer->SortChildrenBy3DZOrder(children);

  /**
   * Render this container's contents.
   */
  for (uint32_t i = 0; i < children.Length(); i++) {
    LayerComposite* layerToRender = static_cast<LayerComposite*>(children.ElementAt(i)->ImplData());

    if (layerToRender->GetLayer()->GetEffectiveVisibleRegion().IsEmpty() &&
        !layerToRender->GetLayer()->AsContainerLayer()) {
      continue;
    }

    nsIntRect clipRect = layerToRender->GetLayer()->
        CalculateScissorRect(aClipRect, &aManager->GetWorldTransform());
    if (clipRect.IsEmpty()) {
      continue;
    }

    layerToRender->RenderLayer(childOffset, clipRect);
    // invariant: our GL context should be current here, I don't think we can
    // assert it though
//.........这里部分代码省略.........

// ContainerRender is shared between RefLayer and ContainerLayer
template<class ContainerT> void
ContainerRender(ContainerT* aContainer,
                LayerManagerComposite* aManager,
                const nsIntRect& aClipRect)
{
  /**
   * Setup our temporary surface for rendering the contents of this container.
   */
  RefPtr<CompositingRenderTarget> surface;

  Compositor* compositor = aManager->GetCompositor();

  RefPtr<CompositingRenderTarget> previousTarget = compositor->GetCurrentRenderTarget();

  nsIntRect visibleRect = aContainer->GetEffectiveVisibleRegion().GetBounds();

  float opacity = aContainer->GetEffectiveOpacity();

  bool needsSurface = aContainer->UseIntermediateSurface();
  bool surfaceCopyNeeded;
  aContainer->DefaultComputeSupportsComponentAlphaChildren(&surfaceCopyNeeded);
  if (needsSurface) {
    SurfaceInitMode mode = INIT_MODE_CLEAR;
    gfx::IntRect surfaceRect = gfx::IntRect(visibleRect.x, visibleRect.y,
                                            visibleRect.width, visibleRect.height);
    // we're about to create a framebuffer backed by textures to use as an intermediate
    // surface. What to do if its size (as given by framebufferRect) would exceed the
    // maximum texture size supported by the GL? The present code chooses the compromise
    // of just clamping the framebuffer's size to the max supported size.
    // This gives us a lower resolution rendering of the intermediate surface (children layers).
    // See bug 827170 for a discussion.
    int32_t maxTextureSize = compositor->GetMaxTextureSize();
    surfaceRect.width = std::min(maxTextureSize, surfaceRect.width);
    surfaceRect.height = std::min(maxTextureSize, surfaceRect.height);
    if (aContainer->GetEffectiveVisibleRegion().GetNumRects() == 1 &&
        (aContainer->GetContentFlags() & Layer::CONTENT_OPAQUE))
    {
      mode = INIT_MODE_NONE;
    }

    if (surfaceCopyNeeded) {
      gfx::IntPoint sourcePoint = gfx::IntPoint(visibleRect.x, visibleRect.y);

      gfx::Matrix4x4 transform = aContainer->GetEffectiveTransform();
      DebugOnly<gfx::Matrix> transform2d;
      MOZ_ASSERT(transform.Is2D(&transform2d) && !gfx::ThebesMatrix(transform2d).HasNonIntegerTranslation());
      sourcePoint += gfx::IntPoint(transform._41, transform._42);

      sourcePoint -= compositor->GetCurrentRenderTarget()->GetOrigin();

      surface = compositor->CreateRenderTargetFromSource(surfaceRect, previousTarget, sourcePoint);
    } else {
      surface = compositor->CreateRenderTarget(surfaceRect, mode);
    }

    if (!surface) {
      return;
    }

    compositor->SetRenderTarget(surface);
  } else {
    surface = previousTarget;
  }

  nsAutoTArray<Layer*, 12> children;
  aContainer->SortChildrenBy3DZOrder(children);

  // If this is a scrollable container layer, and it's overscrolled, the layer's
  // contents are transformed in a way that would leave blank regions in the
  // composited area. If the layer has a background color, fill these areas
  // with the background color by drawing a rectangle of the background color
  // over the entire composited area before drawing the container contents.
  if (AsyncPanZoomController* apzc = aContainer->GetAsyncPanZoomController()) {
    // Make sure not to do this on a "scrollinfo" layer (one with an empty visible
    // region) because it's just a placeholder for APZ purposes.
    if (apzc->IsOverscrolled() && !aContainer->GetVisibleRegion().IsEmpty()) {
      gfxRGBA color = aContainer->GetBackgroundColor();
      // If the background is completely transparent, there's no point in
      // drawing anything for it. Hopefully the layers behind, if any, will
      // provide suitable content for the overscroll effect.
      if (color.a != 0.0) {
        EffectChain effectChain(aContainer);
        effectChain.mPrimaryEffect = new EffectSolidColor(ToColor(color));
        gfx::Rect clipRect(aClipRect.x, aClipRect.y, aClipRect.width, aClipRect.height);
        Compositor* compositor = aManager->GetCompositor();
        compositor->DrawQuad(compositor->ClipRectInLayersCoordinates(clipRect),
            clipRect, effectChain, opacity, Matrix4x4());
      }
    }
  }

  /**
   * Render this container's contents.
   */
  for (uint32_t i = 0; i < children.Length(); i++) {
    LayerComposite* layerToRender = static_cast<LayerComposite*>(children.ElementAt(i)->ImplData());

    if (layerToRender->GetLayer()->GetEffectiveVisibleRegion().IsEmpty() &&
        !layerToRender->GetLayer()->AsContainerLayer()) {
//.........这里部分代码省略.........