C++ gfxMatrix类代码示例

void
LayerManagerOGL::SetWorldTransform(const gfxMatrix& aMatrix)
{
    NS_ASSERTION(aMatrix.PreservesAxisAlignedRectangles(),
                 "SetWorldTransform only accepts matrices that satisfy PreservesAxisAlignedRectangles");
    NS_ASSERTION(!aMatrix.HasNonIntegerScale(),
                 "SetWorldTransform only accepts matrices with integer scale");

    mWorldMatrix = aMatrix;
}

/* static */ bool
HwcUtils::PrepareLayerRects(nsIntRect aVisible, const gfxMatrix& aTransform,
                            nsIntRect aClip, nsIntRect aBufferRect,
                            hwc_rect_t* aSourceCrop, hwc_rect_t* aVisibleRegionScreen) {

    gfxRect visibleRect(aVisible);
    gfxRect clip(aClip);
    gfxRect visibleRectScreen = aTransform.TransformBounds(visibleRect);
    // |clip| is guaranteed to be integer
    visibleRectScreen.IntersectRect(visibleRectScreen, clip);

    if (visibleRectScreen.IsEmpty()) {
        LOGD("Skip layer");
        return false;
    }

    gfxMatrix inverse(aTransform);
    inverse.Invert();
    gfxRect crop = inverse.TransformBounds(visibleRectScreen);

    //clip to buffer size
    crop.IntersectRect(crop, aBufferRect);
    crop.Round();

    if (crop.IsEmpty()) {
        LOGD("Skip layer");
        return false;
    }

    //propagate buffer clipping back to visible rect
    visibleRectScreen = aTransform.TransformBounds(crop);
    visibleRectScreen.Round();

    // Map from layer space to buffer space
    crop -= aBufferRect.TopLeft();

    aSourceCrop->left = crop.x;
    aSourceCrop->top  = crop.y;
    aSourceCrop->right  = crop.x + crop.width;
    aSourceCrop->bottom = crop.y + crop.height;

    aVisibleRegionScreen->left = visibleRectScreen.x;
    aVisibleRegionScreen->top  = visibleRectScreen.y;
    aVisibleRegionScreen->right  = visibleRectScreen.x + visibleRectScreen.width;
    aVisibleRegionScreen->bottom = visibleRectScreen.y + visibleRectScreen.height;

    return true;
}

bool
HwcComposer2D::TryRender(Layer* aRoot,
                         const gfxMatrix& aGLWorldTransform)
{
    if (!aGLWorldTransform.PreservesAxisAlignedRectangles()) {
        LOGD("Render aborted. World transform has non-square angle rotation");
        return false;
    }

    MOZ_ASSERT(Initialized());
    if (mList) {
        mList->numHwLayers = 0;
    }

    if (!PrepareLayerList(aRoot,
                          mScreenRect,
                          gfxMatrix(),
                          aGLWorldTransform))
    {
        LOGD("Render aborted. Nothing was drawn to the screen");
        return false;
    }

    if (mHwc->set(mHwc, mDpy, mSur, mList)) {
        LOGE("Hardware device failed to render");
        return false;
    }

    LOGD("Frame rendered");
    return true;
}

/* static */ bool
HwcUtils::CalculateClipRect(const gfxMatrix& aTransform,
                            const nsIntRect* aLayerClip,
                            nsIntRect aParentClip, nsIntRect* aRenderClip) {

    *aRenderClip = aParentClip;

    if (!aLayerClip) {
        return true;
    }

    if (aLayerClip->IsEmpty()) {
        return false;
    }

    nsIntRect clip = *aLayerClip;

    gfxRect r(clip);
    gfxRect trClip = aTransform.TransformBounds(r);
    trClip.Round();
    gfxUtils::GfxRectToIntRect(trClip, &clip);

    aRenderClip->IntersectRect(*aRenderClip, clip);
    return true;
}

/* static */ bool
HwcUtils::PrepareVisibleRegion(const nsIntRegion& aVisible,
                               const gfxMatrix& aTransform,
                               nsIntRect aClip, nsIntRect aBufferRect,
                               RectVector* aVisibleRegionScreen) {

    nsIntRegionRectIterator rect(aVisible);
    bool isVisible = false;
    while (const nsIntRect* visibleRect = rect.Next()) {
        hwc_rect_t visibleRectScreen;
        gfxRect screenRect;

        screenRect.IntersectRect(gfxRect(*visibleRect), aBufferRect);
        screenRect = aTransform.TransformBounds(screenRect);
        screenRect.IntersectRect(screenRect, aClip);
        screenRect.Round();
        if (screenRect.IsEmpty()) {
            continue;
        }
        visibleRectScreen.left = screenRect.x;
        visibleRectScreen.top  = screenRect.y;
        visibleRectScreen.right  = screenRect.XMost();
        visibleRectScreen.bottom = screenRect.YMost();
        aVisibleRegionScreen->push_back(visibleRectScreen);
        isVisible = true;
    }

    return isVisible;
}

imgFrame::SurfaceWithFormat
imgFrame::SurfaceForDrawing(bool               aDoPadding,
                            bool               aDoPartialDecode,
                            bool               aDoTile,
                            const nsIntMargin& aPadding,
                            gfxMatrix&         aUserSpaceToImageSpace,
                            gfxRect&           aFill,
                            gfxRect&           aSubimage,
                            gfxRect&           aSourceRect,
                            gfxRect&           aImageRect)
{
  gfxIntSize size(PRInt32(aImageRect.Width()), PRInt32(aImageRect.Height()));
  if (!aDoPadding && !aDoPartialDecode) {
    NS_ASSERTION(!mSinglePixel, "This should already have been handled");
    return SurfaceWithFormat(new gfxSurfaceDrawable(ThebesSurface(), size), mFormat);
  }

  gfxRect available = gfxRect(mDecoded.x, mDecoded.y, mDecoded.width, mDecoded.height);

  if (aDoTile || mSinglePixel) {
    // Create a temporary surface.
    // Give this surface an alpha channel because there are
    // transparent pixels in the padding or undecoded area
    gfxImageSurface::gfxImageFormat format = gfxASurface::ImageFormatARGB32;
    nsRefPtr<gfxASurface> surface =
      gfxPlatform::GetPlatform()->CreateOffscreenSurface(size, gfxImageSurface::ContentFromFormat(format));
    if (!surface || surface->CairoStatus())
      return SurfaceWithFormat();

    // Fill 'available' with whatever we've got
    gfxContext tmpCtx(surface);
    tmpCtx.SetOperator(gfxContext::OPERATOR_SOURCE);
    if (mSinglePixel) {
      tmpCtx.SetDeviceColor(mSinglePixelColor);
    } else {
      tmpCtx.SetSource(ThebesSurface(), gfxPoint(aPadding.left, aPadding.top));
    }
    tmpCtx.Rectangle(available);
    tmpCtx.Fill();
    return SurfaceWithFormat(new gfxSurfaceDrawable(surface, size), format);
  }

  // Not tiling, and we have a surface, so we can account for
  // padding and/or a partial decode just by twiddling parameters.
  // First, update our user-space fill rect.
  aSourceRect = aSourceRect.Intersect(available);
  gfxMatrix imageSpaceToUserSpace = aUserSpaceToImageSpace;
  imageSpaceToUserSpace.Invert();
  aFill = imageSpaceToUserSpace.Transform(aSourceRect);

  aSubimage = aSubimage.Intersect(available) - gfxPoint(aPadding.left, aPadding.top);
  aUserSpaceToImageSpace.Multiply(gfxMatrix().Translate(-gfxPoint(aPadding.left, aPadding.top)));
  aSourceRect = aSourceRect - gfxPoint(aPadding.left, aPadding.top);
  aImageRect = gfxRect(0, 0, mSize.width, mSize.height);

  gfxIntSize availableSize(mDecoded.width, mDecoded.height);
  return SurfaceWithFormat(new gfxSurfaceDrawable(ThebesSurface(),
                                                  availableSize),
                           mFormat);
}

gfxMatrix
nsSVGGraphicElement::PrependLocalTransformsTo(const gfxMatrix &aMatrix,
                                              TransformTypes aWhich) const
{
  NS_ABORT_IF_FALSE(aWhich != eChildToUserSpace || aMatrix.IsIdentity(),
                    "Skipping eUserSpaceToParent transforms makes no sense");

  gfxMatrix result(aMatrix);

  if (aWhich == eChildToUserSpace) {
    // We don't have anything to prepend.
    // eChildToUserSpace is not the common case, which is why we return
    // 'result' to benefit from NRVO rather than returning aMatrix before
    // creating 'result'.
    return result;
  }

  NS_ABORT_IF_FALSE(aWhich == eAllTransforms || aWhich == eUserSpaceToParent,
                    "Unknown TransformTypes");

  // animateMotion's resulting transform is supposed to apply *on top of*
  // any transformations from the |transform| attribute. So since we're
  // PRE-multiplying, we need to apply the animateMotion transform *first*.
  if (mAnimateMotionTransform) {
    result.PreMultiply(*mAnimateMotionTransform);
  }

  if (mTransforms) {
    result.PreMultiply(mTransforms->GetAnimValue().GetConsolidationMatrix());
  }

  return result;
}

bool
gfxSurfaceDrawable::Draw(gfxContext* aContext,
                         const gfxRect& aFillRect,
                         bool aRepeat,
                         const GraphicsFilter& aFilter,
                         const gfxMatrix& aTransform)
{
    nsRefPtr<gfxPattern> pattern = new gfxPattern(mSurface);
    if (aRepeat) {
        pattern->SetExtend(gfxPattern::EXTEND_REPEAT);
        pattern->SetFilter(aFilter);
    } else {
        GraphicsFilter filter = aFilter;
        if (aContext->CurrentMatrix().HasOnlyIntegerTranslation() &&
            aTransform.HasOnlyIntegerTranslation())
        {
          // If we only have integer translation, no special filtering needs to
          // happen and we explicitly use FILTER_FAST. This is fast for some
          // backends.
          filter = GraphicsFilter::FILTER_FAST;
        }
        nsRefPtr<gfxASurface> currentTarget = aContext->CurrentSurface();
        gfxMatrix deviceSpaceToImageSpace =
            DeviceToImageTransform(aContext, aTransform);
        PreparePatternForUntiledDrawing(pattern, deviceSpaceToImageSpace,
                                        currentTarget, filter);
    }
    pattern->SetMatrix(gfxMatrix(aTransform).Multiply(mTransform));
    aContext->NewPath();
    aContext->SetPattern(pattern);
    aContext->Rectangle(aFillRect);
    aContext->Fill();
    return true;
}

/**
 * Returns the app unit canvas bounds of a userspace rect.
 *
 * @param aToCanvas Transform from userspace to canvas device space.
 */
static nsRect
ToCanvasBounds(const gfxRect &aUserspaceRect,
               const gfxMatrix &aToCanvas,
               const nsPresContext *presContext)
{
  return nsLayoutUtils::RoundGfxRectToAppRect(
                          aToCanvas.TransformBounds(aUserspaceRect),
                          presContext->AppUnitsPerDevPixel());
}

/* [noscript] void draw(in gfxContext aContext,
 *                      in gfxGraphicsFilter aFilter,
 *                      [const] in gfxMatrix aUserSpaceToImageSpace,
 *                      [const] in gfxRect aFill,
 *                      [const] in nsIntRect aSubimage,
 *                      [const] in nsIntSize aViewportSize,
 *                      in PRUint32 aFlags); */
NS_IMETHODIMP
VectorImage::Draw(gfxContext* aContext,
                  gfxPattern::GraphicsFilter aFilter,
                  const gfxMatrix& aUserSpaceToImageSpace,
                  const gfxRect& aFill,
                  const nsIntRect& aSubimage,
                  const nsIntSize& aViewportSize,
                  PRUint32 aFlags)
{
  NS_ENSURE_ARG_POINTER(aContext);
  if (mError || !mIsFullyLoaded)
    return NS_ERROR_FAILURE;

  if (mIsDrawing) {
    NS_WARNING("Refusing to make re-entrant call to VectorImage::Draw");
    return NS_ERROR_FAILURE;
  }
  mIsDrawing = true;

  if (aViewportSize != mLastRenderedSize) {
    mSVGDocumentWrapper->UpdateViewportBounds(aViewportSize);
    mLastRenderedSize = aViewportSize;
  }
  mSVGDocumentWrapper->FlushImageTransformInvalidation();

  nsIntSize imageSize = mHaveRestrictedRegion ?
    mRestrictedRegion.Size() : aViewportSize;

  // XXXdholbert Do we need to convert image size from
  // CSS pixels to dev pixels here? (is gfxCallbackDrawable's 2nd arg in dev
  // pixels?)
  gfxIntSize imageSizeGfx(imageSize.width, imageSize.height);

  // Based on imgFrame::Draw
  gfxRect sourceRect = aUserSpaceToImageSpace.Transform(aFill);
  gfxRect imageRect(0, 0, imageSize.width, imageSize.height);
  gfxRect subimage(aSubimage.x, aSubimage.y, aSubimage.width, aSubimage.height);


  nsRefPtr<gfxDrawingCallback> cb =
    new SVGDrawingCallback(mSVGDocumentWrapper,
                           mHaveRestrictedRegion ?
                           mRestrictedRegion :
                           nsIntRect(nsIntPoint(0, 0), aViewportSize),
                           aFlags);

  nsRefPtr<gfxDrawable> drawable = new gfxCallbackDrawable(cb, imageSizeGfx);

  gfxUtils::DrawPixelSnapped(aContext, drawable,
                             aUserSpaceToImageSpace,
                             subimage, sourceRect, imageRect, aFill,
                             gfxASurface::ImageFormatARGB32, aFilter);

  mIsDrawing = false;
  return NS_OK;
}

// EXTEND_PAD won't help us here; we have to create a temporary surface to hold
// the subimage of pixels we're allowed to sample.
static already_AddRefed<gfxDrawable>
CreateSamplingRestrictedDrawable(gfxDrawable* aDrawable,
                                 gfxContext* aContext,
                                 const gfxMatrix& aUserSpaceToImageSpace,
                                 const gfxRect& aSourceRect,
                                 const gfxRect& aSubimage,
                                 const gfxImageFormat aFormat)
{
    PROFILER_LABEL("gfxUtils", "CreateSamplingRestricedDrawable");
    gfxRect userSpaceClipExtents = aContext->GetClipExtents();
    // This isn't optimal --- if aContext has a rotation then GetClipExtents
    // will have to do a bounding-box computation, and TransformBounds might
    // too, so we could get a better result if we computed image space clip
    // extents in one go --- but it doesn't really matter and this is easier
    // to understand.
    gfxRect imageSpaceClipExtents =
        aUserSpaceToImageSpace.TransformBounds(userSpaceClipExtents);
    // Inflate by one pixel because bilinear filtering will sample at most
    // one pixel beyond the computed image pixel coordinate.
    imageSpaceClipExtents.Inflate(1.0);

    gfxRect needed = imageSpaceClipExtents.Intersect(aSourceRect);
    needed = needed.Intersect(aSubimage);
    needed.RoundOut();

    // if 'needed' is empty, nothing will be drawn since aFill
    // must be entirely outside the clip region, so it doesn't
    // matter what we do here, but we should avoid trying to
    // create a zero-size surface.
    if (needed.IsEmpty())
        return nullptr;

    nsRefPtr<gfxDrawable> drawable;
    gfxIntSize size(int32_t(needed.Width()), int32_t(needed.Height()));

    nsRefPtr<gfxImageSurface> image = aDrawable->GetAsImageSurface();
    if (image && gfxRect(0, 0, image->GetSize().width, image->GetSize().height).Contains(needed)) {
      nsRefPtr<gfxASurface> temp = image->GetSubimage(needed);
      drawable = new gfxSurfaceDrawable(temp, size, gfxMatrix().Translate(-needed.TopLeft()));
    } else {
      mozilla::RefPtr<mozilla::gfx::DrawTarget> target =
        gfxPlatform::GetPlatform()->CreateOffscreenContentDrawTarget(ToIntSize(size),
                                                                     ImageFormatToSurfaceFormat(aFormat));
      if (!target) {
        return nullptr;
      }

      nsRefPtr<gfxContext> tmpCtx = new gfxContext(target);
      tmpCtx->SetOperator(OptimalFillOperator());
      aDrawable->Draw(tmpCtx, needed - needed.TopLeft(), true,
                      GraphicsFilter::FILTER_FAST, gfxMatrix().Translate(needed.TopLeft()));
      drawable = new gfxSurfaceDrawable(target, size, gfxMatrix().Translate(-needed.TopLeft()));
    }

    return drawable.forget();
}

SVGBBox
nsSVGForeignObjectFrame::GetBBoxContribution(const gfxMatrix &aToBBoxUserspace,
                                             PRUint32 aFlags)
{
  nsSVGForeignObjectElement *content =
    static_cast<nsSVGForeignObjectElement*>(mContent);

  float x, y, w, h;
  content->GetAnimatedLengthValues(&x, &y, &w, &h, nsnull);

  if (w < 0.0f) w = 0.0f;
  if (h < 0.0f) h = 0.0f;

  if (aToBBoxUserspace.IsSingular()) {
    // XXX ReportToConsole
    return SVGBBox();
  }
  return aToBBoxUserspace.TransformBounds(gfxRect(0.0, 0.0, w, h));
}

gfxRect
nsSVGPathGeometryFrame::GetBBoxContribution(const gfxMatrix &aToBBoxUserspace)
{
  if (aToBBoxUserspace.IsSingular()) {
    // XXX ReportToConsole
    return gfxRect(0.0, 0.0, 0.0, 0.0);
  }
  gfxContext context(nsSVGUtils::GetThebesComputationalSurface());
  GeneratePath(&context, &aToBBoxUserspace);
  context.IdentityMatrix();
  return context.GetUserPathExtent();
}

gfxRect
nsSVGForeignObjectFrame::GetBBoxContribution(const gfxMatrix &aToBBoxUserspace)
{
  NS_ASSERTION(!(GetStateBits() & NS_STATE_SVG_NONDISPLAY_CHILD),
               "Should not be calling this on a non-display child");

  nsSVGForeignObjectElement *content =
    static_cast<nsSVGForeignObjectElement*>(mContent);

  float x, y, w, h;
  content->GetAnimatedLengthValues(&x, &y, &w, &h, nsnull);

  if (w < 0.0f) w = 0.0f;
  if (h < 0.0f) h = 0.0f;

  if (aToBBoxUserspace.IsSingular()) {
    // XXX ReportToConsole
    return gfxRect(0.0, 0.0, 0.0, 0.0);
  }
  return aToBBoxUserspace.TransformBounds(gfxRect(0.0, 0.0, w, h));
}

bool
gfxSurfaceDrawable::Draw(gfxContext* aContext,
                         const gfxRect& aFillRect,
                         bool aRepeat,
                         const GraphicsFilter& aFilter,
                         const gfxMatrix& aTransform)
{
    nsRefPtr<gfxPattern> pattern;
    if (mDrawTarget) {
        if (aContext->IsCairo()) {
            nsRefPtr<gfxASurface> source =
                gfxPlatform::GetPlatform()->GetThebesSurfaceForDrawTarget(mDrawTarget);
            pattern = new gfxPattern(source);
        } else {
            RefPtr<SourceSurface> source = mDrawTarget->Snapshot();
            pattern = new gfxPattern(source, Matrix());
        }
    } else if (mSourceSurface) {
        pattern = new gfxPattern(mSourceSurface, Matrix());
    } else {
        pattern = new gfxPattern(mSurface);
    }
    if (aRepeat) {
        pattern->SetExtend(gfxPattern::EXTEND_REPEAT);
        pattern->SetFilter(aFilter);
    } else {
        GraphicsFilter filter = aFilter;
        if (aContext->CurrentMatrix().HasOnlyIntegerTranslation() &&
                aTransform.HasOnlyIntegerTranslation())
        {
            // If we only have integer translation, no special filtering needs to
            // happen and we explicitly use FILTER_FAST. This is fast for some
            // backends.
            filter = GraphicsFilter::FILTER_FAST;
        }
        nsRefPtr<gfxASurface> currentTarget = aContext->CurrentSurface();
        gfxMatrix deviceSpaceToImageSpace =
            DeviceToImageTransform(aContext, aTransform);
        PreparePatternForUntiledDrawing(pattern, deviceSpaceToImageSpace,
                                        currentTarget, filter);
    }
    pattern->SetMatrix(gfxMatrix(aTransform).Multiply(mTransform));
    aContext->NewPath();
    aContext->SetPattern(pattern);
    aContext->Rectangle(aFillRect);
    aContext->Fill();
    // clear the pattern so that the snapshot is released before the
    // drawable is destroyed
    aContext->SetDeviceColor(gfxRGBA(0.0, 0.0, 0.0, 0.0));
    return true;
}