C++ Matrix4x4::PreScale方法代码示例

void
TiledContentHost::RenderLayerBuffer(TiledLayerBufferComposite& aLayerBuffer,
                                    const gfxRGBA* aBackgroundColor,
                                    EffectChain& aEffectChain,
                                    float aOpacity,
                                    const gfx::Filter& aFilter,
                                    const gfx::Rect& aClipRect,
                                    nsIntRegion aVisibleRegion,
                                    gfx::Matrix4x4 aTransform)
{
  if (!mCompositor) {
    NS_WARNING("Can't render tiled content host - no compositor");
    return;
  }
  float resolution = aLayerBuffer.GetResolution();
  gfx::Size layerScale(1, 1);

  // We assume that the current frame resolution is the one used in our high
  // precision layer buffer. Compensate for a changing frame resolution when
  // rendering the low precision buffer.
  if (aLayerBuffer.GetFrameResolution() != mTiledBuffer.GetFrameResolution()) {
    const CSSToParentLayerScale& layerResolution = aLayerBuffer.GetFrameResolution();
    const CSSToParentLayerScale& localResolution = mTiledBuffer.GetFrameResolution();
    layerScale.width = layerScale.height = layerResolution.scale / localResolution.scale;
    aVisibleRegion.ScaleRoundOut(layerScale.width, layerScale.height);
  }

  // If we're drawing the low precision buffer, make sure the high precision
  // buffer is masked out to avoid overdraw and rendering artifacts with
  // non-opaque layers.
  nsIntRegion maskRegion;
  if (resolution != mTiledBuffer.GetResolution()) {
    maskRegion = mTiledBuffer.GetValidRegion();
    // XXX This should be ScaleRoundIn, but there is no such function on
    //     nsIntRegion.
    maskRegion.ScaleRoundOut(layerScale.width, layerScale.height);
  }

  // Make sure the resolution and difference in frame resolution are accounted
  // for in the layer transform.
  aTransform.PreScale(1/(resolution * layerScale.width),
                      1/(resolution * layerScale.height), 1);

  uint32_t rowCount = 0;
  uint32_t tileX = 0;
  nsIntRect visibleRect = aVisibleRegion.GetBounds();
  gfx::IntSize scaledTileSize = aLayerBuffer.GetScaledTileSize();
  for (int32_t x = visibleRect.x; x < visibleRect.x + visibleRect.width;) {
    rowCount++;
    int32_t tileStartX = aLayerBuffer.GetTileStart(x, scaledTileSize.width);
    int32_t w = scaledTileSize.width - tileStartX;
    if (x + w > visibleRect.x + visibleRect.width) {
      w = visibleRect.x + visibleRect.width - x;
    }
    int tileY = 0;
    for (int32_t y = visibleRect.y; y < visibleRect.y + visibleRect.height;) {
      int32_t tileStartY = aLayerBuffer.GetTileStart(y, scaledTileSize.height);
      int32_t h = scaledTileSize.height - tileStartY;
      if (y + h > visibleRect.y + visibleRect.height) {
        h = visibleRect.y + visibleRect.height - y;
      }

      TileHost tileTexture = aLayerBuffer.
        GetTile(nsIntPoint(aLayerBuffer.RoundDownToTileEdge(x, scaledTileSize.width),
                           aLayerBuffer.RoundDownToTileEdge(y, scaledTileSize.height)));
      if (tileTexture != aLayerBuffer.GetPlaceholderTile()) {
        nsIntRegion tileDrawRegion;
        tileDrawRegion.And(nsIntRect(x, y, w, h), aLayerBuffer.GetValidRegion());
        tileDrawRegion.And(tileDrawRegion, aVisibleRegion);
        tileDrawRegion.Sub(tileDrawRegion, maskRegion);

        if (!tileDrawRegion.IsEmpty()) {
          tileDrawRegion.ScaleRoundOut(resolution, resolution);
          nsIntPoint tileOffset((x - tileStartX) * resolution,
                                (y - tileStartY) * resolution);
          gfx::IntSize tileSize = aLayerBuffer.GetTileSize();
          RenderTile(tileTexture, aBackgroundColor, aEffectChain, aOpacity, aTransform,
                     aFilter, aClipRect, tileDrawRegion, tileOffset,
                     nsIntSize(tileSize.width, tileSize.height));
        }
      }
      tileY++;
      y += h;
    }
    tileX++;
    x += w;
  }
  gfx::Rect rect(visibleRect.x, visibleRect.y,
                 visibleRect.width, visibleRect.height);
  GetCompositor()->DrawDiagnostics(DiagnosticFlags::CONTENT,
                                   rect, aClipRect, aTransform, mFlashCounter);
}

void
TiledContentHost::RenderLayerBuffer(TiledLayerBufferComposite& aLayerBuffer,
                                    const gfxRGBA* aBackgroundColor,
                                    EffectChain& aEffectChain,
                                    float aOpacity,
                                    const gfx::Filter& aFilter,
                                    const gfx::Rect& aClipRect,
                                    nsIntRegion aVisibleRegion,
                                    gfx::Matrix4x4 aTransform)
{
  if (!mCompositor) {
    NS_WARNING("Can't render tiled content host - no compositor");
    return;
  }
  float resolution = aLayerBuffer.GetResolution();
  gfx::Size layerScale(1, 1);

  // We assume that the current frame resolution is the one used in our high
  // precision layer buffer. Compensate for a changing frame resolution when
  // rendering the low precision buffer.
  if (aLayerBuffer.GetFrameResolution() != mTiledBuffer.GetFrameResolution()) {
    const CSSToParentLayerScale2D& layerResolution = aLayerBuffer.GetFrameResolution();
    const CSSToParentLayerScale2D& localResolution = mTiledBuffer.GetFrameResolution();
    layerScale.width = layerResolution.xScale / localResolution.xScale;
    layerScale.height = layerResolution.yScale / localResolution.yScale;
    aVisibleRegion.ScaleRoundOut(layerScale.width, layerScale.height);
  }

  // Make sure we don't render at low resolution where we have valid high
  // resolution content, to avoid overdraw and artifacts with semi-transparent
  // layers.
  nsIntRegion maskRegion;
  if (resolution != mTiledBuffer.GetResolution()) {
    maskRegion = mTiledBuffer.GetValidRegion();
    // XXX This should be ScaleRoundIn, but there is no such function on
    //     nsIntRegion.
    maskRegion.ScaleRoundOut(layerScale.width, layerScale.height);
  }

  // Make sure the resolution and difference in frame resolution are accounted
  // for in the layer transform.
  aTransform.PreScale(1/(resolution * layerScale.width),
                      1/(resolution * layerScale.height), 1);

  DiagnosticFlags componentAlphaDiagnostic = DiagnosticFlags::NO_DIAGNOSTIC;

  nsIntRegion compositeRegion = aLayerBuffer.GetValidRegion();
  compositeRegion.AndWith(aVisibleRegion);
  compositeRegion.SubOut(maskRegion);

  IntRect visibleRect = aVisibleRegion.GetBounds();

  if (compositeRegion.IsEmpty()) {
    return;
  }

  if (aBackgroundColor) {
    nsIntRegion backgroundRegion = compositeRegion;
    backgroundRegion.ScaleRoundOut(resolution, resolution);
    EffectChain effect;
    effect.mPrimaryEffect = new EffectSolidColor(ToColor(*aBackgroundColor));
    nsIntRegionRectIterator it(backgroundRegion);
    for (const IntRect* rect = it.Next(); rect != nullptr; rect = it.Next()) {
      Rect graphicsRect(rect->x, rect->y, rect->width, rect->height);
      mCompositor->DrawQuad(graphicsRect, aClipRect, effect, 1.0, aTransform);
    }
  }

  for (size_t i = 0; i < aLayerBuffer.GetTileCount(); ++i) {
    TileHost& tile = aLayerBuffer.GetTile(i);
    if (tile.IsPlaceholderTile()) {
      continue;
    }

    TileIntPoint tilePosition = aLayerBuffer.GetPlacement().TilePosition(i);
    // A sanity check that catches a lot of mistakes.
    MOZ_ASSERT(tilePosition.x == tile.mTilePosition.x && tilePosition.y == tile.mTilePosition.y);

    IntPoint tileOffset = aLayerBuffer.GetTileOffset(tilePosition);
    nsIntRegion tileDrawRegion = IntRect(tileOffset, aLayerBuffer.GetScaledTileSize());
    tileDrawRegion.AndWith(compositeRegion);

    if (tileDrawRegion.IsEmpty()) {
      continue;
    }

    tileDrawRegion.ScaleRoundOut(resolution, resolution);
    RenderTile(tile, aEffectChain, aOpacity,
               aTransform, aFilter, aClipRect, tileDrawRegion,
               tileOffset * resolution, aLayerBuffer.GetTileSize(),
               gfx::Rect(visibleRect.x, visibleRect.y,
                         visibleRect.width, visibleRect.height));
    if (tile.mTextureHostOnWhite) {
      componentAlphaDiagnostic = DiagnosticFlags::COMPONENT_ALPHA;
    }
  }

  gfx::Rect rect(visibleRect.x, visibleRect.y,
                 visibleRect.width, visibleRect.height);
  GetCompositor()->DrawDiagnostics(DiagnosticFlags::CONTENT | componentAlphaDiagnostic,
//.........这里部分代码省略.........