///<devdoc> /// Creates a new clipping region from the intersection of the current clipping region and /// the specified rectangle. ///</devdoc> public void IntersectClip(WindowsRegion wr) { //if the incoming windowsregion is infinite, there is no need to do any intersecting. if (wr.HRegion == IntPtr.Zero) { return; } WindowsRegion clip = new WindowsRegion(0, 0, 0, 0); try { int result = IntUnsafeNativeMethods.GetClipRgn(new HandleRef(this, this.Hdc), new HandleRef(clip, clip.HRegion)); // If the function succeeds and there is a clipping region for the given device context, the return value is 1. if (result == 1) { Debug.Assert(clip.HRegion != IntPtr.Zero); wr.CombineRegion(clip, wr, RegionCombineMode.AND); //1 = AND (or Intersect) } SetClip(wr); } finally { clip.Dispose(); } }
public void IntersectClip(WindowsRegion wr) { //if the incoming windowsregion is infinite, there is no need to do any intersecting. if (wr.HRegion == IntPtr.Zero) { return; } WindowsRegion clip = new WindowsRegion(0,0,0,0); try { int result = IntUnsafeNativeMethods.GetClipRgn(new HandleRef( this, this.Hdc), new HandleRef(clip, clip.HRegion)); // If the function succeeds and there is a clipping region for the given device context, the return value is 1. if (result == 1) { Debug.Assert(clip.HRegion != IntPtr.Zero); wr.CombineRegion(clip, wr, RegionCombineMode.AND); //1 = AND (or Intersect) } SetClip(wr); } finally { clip.Dispose(); } }