Direct2D (24) : 合并几何对象
合并通过 ID2D1Geometry.CombineWithGeometry() 完成,但返回的是 ID2D1SimplifiedGeometrySink(ID2D1GeometrySink 的父对象);
需要把 ID2D1SimplifiedGeometrySink 添加到 ID2D1PathGeometry 才能使用。
uses Direct2D, D2D1; procedure TForm1.FormPaint(Sender: TObject); var cvs: TDirect2DCanvas; iEllipseGeometry1, iEllipseGeometry2: ID2D1EllipseGeometry; iGeometrySink: ID2D1GeometrySink; iPathGeometry1,iPathGeometry2,iPathGeometry3,iPathGeometry4: ID2D1PathGeometry; ptCenter: TD2DPoint2f; r: Single; matrix: TD2DMatrix3x2F; begin ptCenter := D2D1PointF(100, 100); r := 50; matrix := TD2DMatrix3x2F.Identity; {两个源对象} D2DFactory.CreateEllipseGeometry(D2D1Ellipse(ptCenter, r, r), iEllipseGeometry1); ptCenter.x := ptCenter.x + r; D2DFactory.CreateEllipseGeometry(D2D1Ellipse(ptCenter, r, r), iEllipseGeometry2); {UNION 运算} D2DFactory.CreatePathGeometry(iPathGeometry1); iPathGeometry1.Open(iGeometrySink); iEllipseGeometry1.CombineWithGeometry(iEllipseGeometry2, D2D1_COMBINE_MODE_UNION, matrix, 0, iGeometrySink); iGeometrySink.Close; {INTERSECT 运算} D2DFactory.CreatePathGeometry(iPathGeometry2); iPathGeometry2.Open(iGeometrySink); iEllipseGeometry1.CombineWithGeometry(iEllipseGeometry2, D2D1_COMBINE_MODE_INTERSECT, matrix, 0, iGeometrySink); iGeometrySink.Close; {XOR 运算} D2DFactory.CreatePathGeometry(iPathGeometry3); iPathGeometry3.Open(iGeometrySink); iEllipseGeometry1.CombineWithGeometry(iEllipseGeometry2, D2D1_COMBINE_MODE_XOR, matrix, 0, iGeometrySink); iGeometrySink.Close; {EXCLUDE 运算} D2DFactory.CreatePathGeometry(iPathGeometry4); iPathGeometry4.Open(iGeometrySink); iEllipseGeometry1.CombineWithGeometry(iEllipseGeometry2, D2D1_COMBINE_MODE_EXCLUDE, matrix, 0, iGeometrySink); iGeometrySink.Close; cvs := TDirect2DCanvas.Create(Canvas, ClientRect); cvs.BeginDraw; cvs.Pen.Color := clWebCornFlowerBlue; cvs.Brush.Color := clWebCornFlowerBlue; cvs.Brush.Handle.SetOpacity(0.75); cvs.FillGeometry(iPathGeometry1); cvs.DrawGeometry(iEllipseGeometry1); cvs.DrawGeometry(iEllipseGeometry2); cvs.RenderTarget.SetTransform(TD2DMatrix3x2F.Translation(180, 0)); cvs.FillGeometry(iPathGeometry2); cvs.DrawGeometry(iEllipseGeometry1); cvs.DrawGeometry(iEllipseGeometry2); cvs.RenderTarget.SetTransform(TD2DMatrix3x2F.Translation(180*2, 0)); cvs.FillGeometry(iPathGeometry3); cvs.DrawGeometry(iEllipseGeometry1); cvs.DrawGeometry(iEllipseGeometry2); cvs.RenderTarget.SetTransform(TD2DMatrix3x2F.Translation(180*3, 0)); cvs.FillGeometry(iPathGeometry4); cvs.DrawGeometry(iEllipseGeometry1); cvs.DrawGeometry(iEllipseGeometry2); cvs.EndDraw; cvs.Free; end;
效果图:
简化后的代码:
uses Direct2D, D2D1; procedure TForm1.FormPaint(Sender: TObject); var cvs: TDirect2DCanvas; iEllipseGeometry1, iEllipseGeometry2: ID2D1EllipseGeometry; iGeometrySink: ID2D1GeometrySink; iPathGeometrys: array[0..3] of ID2D1PathGeometry; ptCenter: TD2DPoint2f; r: Single; i: Integer; begin ptCenter := D2D1PointF(100, 100); r := 50; D2DFactory.CreateEllipseGeometry(D2D1Ellipse(ptCenter, r, r), iEllipseGeometry1); ptCenter.x := ptCenter.x + r; D2DFactory.CreateEllipseGeometry(D2D1Ellipse(ptCenter, r, r), iEllipseGeometry2); for i := 0 to 3 do begin D2DFactory.CreatePathGeometry(iPathGeometrys[i]); iPathGeometrys[i].Open(iGeometrySink); iEllipseGeometry1.CombineWithGeometry(iEllipseGeometry2, i, TD2DMatrix3x2F.Identity, 0, iGeometrySink); iGeometrySink.Close; end; cvs := TDirect2DCanvas.Create(Canvas, ClientRect); cvs.BeginDraw; cvs.Pen.Color := clWebCornFlowerBlue; cvs.Brush.Color := clWebCornFlowerBlue; cvs.Brush.Handle.SetOpacity(0.75); for i := 0 to 3 do begin cvs.RenderTarget.SetTransform(TD2DMatrix3x2F.Translation(180*i, 0)); cvs.FillGeometry(iPathGeometrys[i]); cvs.DrawGeometry(iEllipseGeometry1); cvs.DrawGeometry(iEllipseGeometry2); end; cvs.EndDraw; cvs.Free; end;
posted on 2011-04-06 20:39 万一 阅读(1543) 评论(0) 编辑 收藏