示例#1
0
static void
RecenterDisplayPort(mozilla::layers::FrameMetrics& aFrameMetrics)
{
    LayerMargin margins = aFrameMetrics.GetDisplayPortMargins();
    margins.right = margins.left = margins.LeftRight() / 2;
    margins.top = margins.bottom = margins.TopBottom() / 2;
    aFrameMetrics.SetDisplayPortMargins(margins);
}
示例#2
0
static void
AdjustDisplayPortForScrollDelta(mozilla::layers::FrameMetrics& aFrameMetrics,
                                const CSSPoint& aActualScrollOffset)
{
    // Correct the display-port by the difference between the requested scroll
    // offset and the resulting scroll offset after setting the requested value.
    LayerPoint shift =
        (aFrameMetrics.GetScrollOffset() - aActualScrollOffset) *
        aFrameMetrics.LayersPixelsPerCSSPixel();
    LayerMargin margins = aFrameMetrics.GetDisplayPortMargins();
    margins.left -= shift.x;
    margins.right += shift.x;
    margins.top -= shift.y;
    margins.bottom += shift.y;
    aFrameMetrics.SetDisplayPortMargins(margins);
}