C++ Matrix4x4::PostScale方法代码示例

Matrix4x4
ReadTransforms(const nsCSSValueList* aList,
               nsStyleContext* aContext,
               nsPresContext* aPresContext,
               RuleNodeCacheConditions& aConditions,
               TransformReferenceBox& aRefBox,
               float aAppUnitsPerMatrixUnit,
               bool* aContains3dTransform)
{
  Matrix4x4 result;

  for (const nsCSSValueList* curr = aList; curr != nullptr; curr = curr->mNext) {
    const nsCSSValue &currElem = curr->mValue;
    if (currElem.GetUnit() != eCSSUnit_Function) {
      NS_ASSERTION(currElem.GetUnit() == eCSSUnit_None &&
                   !aList->mNext,
                   "stream should either be a list of functions or a "
                   "lone None");
      continue;
    }
    NS_ASSERTION(currElem.GetArrayValue()->Count() >= 1,
                 "Incoming function is too short!");

    /* Read in a single transform matrix. */
    MatrixForTransformFunction(result, currElem.GetArrayValue(), aContext,
                               aPresContext, aConditions, aRefBox,
                               aContains3dTransform);
  }

  float scale = float(nsPresContext::AppUnitsPerCSSPixel()) / aAppUnitsPerMatrixUnit;
  result.PreScale(1/scale, 1/scale, 1/scale);
  result.PostScale(scale, scale, scale);

  return result;
}

gfx::IntRect
ComputeBackdropCopyRect(const gfx::Rect& aRect,
                        const gfx::IntRect& aClipRect,
                        const gfx::Matrix4x4& aTransform,
                        const gfx::IntRect& aRenderTargetRect,
                        gfx::Matrix4x4* aOutTransform,
                        gfx::Rect* aOutLayerQuad)
{
  // Compute the clip.
  IntPoint rtOffset = aRenderTargetRect.TopLeft();
  IntSize rtSize = aRenderTargetRect.Size();

  gfx::IntRect renderBounds(0, 0, rtSize.width, rtSize.height);
  renderBounds.IntersectRect(renderBounds, aClipRect);
  renderBounds.MoveBy(rtOffset);

  // Apply the layer transform.
  RectDouble dest = aTransform.TransformAndClipBounds(
    RectDouble(aRect.x, aRect.y, aRect.width, aRect.height),
    RectDouble(renderBounds.x, renderBounds.y, renderBounds.width, renderBounds.height));
  dest -= rtOffset;

  // Ensure we don't round out to -1, which trips up Direct3D.
  dest.IntersectRect(dest, RectDouble(0, 0, rtSize.width, rtSize.height));

  if (aOutLayerQuad) {
    *aOutLayerQuad = Rect(dest.x, dest.y, dest.width, dest.height);
  }

  // Round out to integer.
  IntRect result;
  dest.RoundOut();
  dest.ToIntRect(&result);

  // Create a transform from adjusted clip space to render target space,
  // translate it for the backdrop rect, then transform it into the backdrop's
  // uv-space.
  Matrix4x4 transform;
  transform.PostScale(rtSize.width, rtSize.height, 1.0);
  transform.PostTranslate(-result.x, -result.y, 0.0);
  transform.PostScale(1 / float(result.width), 1 / float(result.height), 1.0);
  *aOutTransform = transform;
  return result;
}

Matrix4x4
HostLayer::GetShadowTransform() {
  Matrix4x4 transform = mShadowTransform;
  Layer* layer = GetLayer();

  transform.PostScale(layer->GetPostXScale(), layer->GetPostYScale(), 1.0f);
  if (const ContainerLayer* c = layer->AsContainerLayer()) {
    transform.PreScale(c->GetPreXScale(), c->GetPreYScale(), 1.0f);
  }

  return transform;
}

float
LayerManagerComposite::ComputeRenderIntegrity()
{
  // We only ever have incomplete rendering when progressive tiles are enabled.
  Layer* root = GetRoot();
  if (!gfxPlatform::GetPlatform()->UseProgressivePaint() || !root) {
    return 1.f;
  }

  FrameMetrics rootMetrics = LayerMetricsWrapper::TopmostScrollableMetrics(root);
  if (!rootMetrics.IsScrollable()) {
    // The root may not have any scrollable metrics, in which case rootMetrics
    // will just be an empty FrameMetrics. Instead use the actual metrics from
    // the root layer.
    rootMetrics = LayerMetricsWrapper(root).Metrics();
  }
  ParentLayerIntRect bounds = RoundedToInt(rootMetrics.GetCompositionBounds());
  IntRect screenRect(bounds.x,
                       bounds.y,
                       bounds.width,
                       bounds.height);

  float lowPrecisionMultiplier = 1.0f;
  float highPrecisionMultiplier = 1.0f;

#ifdef MOZ_WIDGET_ANDROID
  // Use the transform on the primary scrollable layer and its FrameMetrics
  // to find out how much of the viewport the current displayport covers
  nsTArray<Layer*> rootScrollableLayers;
  GetRootScrollableLayers(rootScrollableLayers);
  if (rootScrollableLayers.Length() > 0) {
    // This is derived from the code in
    // AsyncCompositionManager::TransformScrollableLayer
    Layer* rootScrollable = rootScrollableLayers[0];
    const FrameMetrics& metrics = LayerMetricsWrapper::TopmostScrollableMetrics(rootScrollable);
    Matrix4x4 transform = rootScrollable->GetEffectiveTransform();
    transform.PostScale(metrics.GetPresShellResolution(), metrics.GetPresShellResolution(), 1);

    // Clip the screen rect to the document bounds
    Rect documentBounds =
      transform.TransformBounds(Rect(metrics.GetScrollableRect().x - metrics.GetScrollOffset().x,
                                     metrics.GetScrollableRect().y - metrics.GetScrollOffset().y,
                                     metrics.GetScrollableRect().width,
                                     metrics.GetScrollableRect().height));
    documentBounds.RoundOut();
    screenRect = screenRect.Intersect(IntRect(documentBounds.x, documentBounds.y,
                                                documentBounds.width, documentBounds.height));

    // If the screen rect is empty, the user has scrolled entirely into
    // over-scroll and so we can be considered to have full integrity.
    if (screenRect.IsEmpty()) {
      return 1.0f;
    }

    // Work out how much of the critical display-port covers the screen
    bool hasLowPrecision = false;
    if (!metrics.GetCriticalDisplayPort().IsEmpty()) {
      hasLowPrecision = true;
      highPrecisionMultiplier =
        GetDisplayportCoverage(metrics.GetCriticalDisplayPort(), transform, screenRect);
    }

    // Work out how much of the display-port covers the screen
    if (!metrics.GetDisplayPort().IsEmpty()) {
      if (hasLowPrecision) {
        lowPrecisionMultiplier =
          GetDisplayportCoverage(metrics.GetDisplayPort(), transform, screenRect);
      } else {
        lowPrecisionMultiplier = highPrecisionMultiplier =
          GetDisplayportCoverage(metrics.GetDisplayPort(), transform, screenRect);
      }
    }
  }

  // If none of the screen is covered, we have zero integrity.
  if (highPrecisionMultiplier <= 0.0f && lowPrecisionMultiplier <= 0.0f) {
    return 0.0f;
  }
#endif // MOZ_WIDGET_ANDROID

  nsIntRegion screenRegion(screenRect);
  nsIntRegion lowPrecisionScreenRegion(screenRect);
  Matrix4x4 transform;
  ComputeRenderIntegrityInternal(root, screenRegion,
                                 lowPrecisionScreenRegion, transform);

  if (!screenRegion.IsEqual(screenRect)) {
    // Calculate the area of the region. All rects in an nsRegion are
    // non-overlapping.
    float screenArea = screenRect.width * screenRect.height;
    float highPrecisionIntegrity = screenRegion.Area() / screenArea;
    float lowPrecisionIntegrity = 1.f;
    if (!lowPrecisionScreenRegion.IsEqual(screenRect)) {
      lowPrecisionIntegrity = lowPrecisionScreenRegion.Area() / screenArea;
    }

    return ((highPrecisionIntegrity * highPrecisionMultiplier) +
            (lowPrecisionIntegrity * lowPrecisionMultiplier)) / 2;
  }

//.........这里部分代码省略.........