{相关方法} TDirect2DCanvas.RenderTarget.SetTransform(); TDirect2DCanvas.RenderTarget.GetTransform(); {相关结构} TD2DMatrix3x2F (或D2D_MATRIX_3X2_F) //因第三列的值在这里是固定的(0,0,1),所以这里用的是 3*2 的矩阵;该结构重载了 * 运算符 {TD2DMatrix3x2FHelper 为 TD2DMatrix3x2F 提供的方法(多为 class 方法)} Identity(); //初始化 TD2DMatrix3x2F,默认值:_11、_22 为 1.0,其它是 0 Translation(); //平移 Scale(); //放缩 Rotation(); //旋转 Skew(); //斜切 Determinant(); //计算行列式 IsInvertible(); //是否可逆 Invert(); //逆向运算 SetProduct(); //乘 {相关全局函数} D2D1MakeRotateMatrix(); //旋转 D2D1MakeSkewMatrix(); //斜切 D2D1IsMatrixInvertible(); //是否可逆 D2D1InvertMatrix(); //逆向运算
测试代码:
uses Direct2D, D2D1; procedure TForm1.FormPaint(Sender: TObject); var cvs: TDirect2DCanvas; pts: array[0..2] of TPoint; matrix: TD2DMatrix3x2F; begin pts[0] := Point(ClientWidth div 2, ClientHeight div 2); pts[1] := Point(ClientWidth div 5, ClientHeight div 2); pts[2] := Point(ClientWidth div 2, ClientHeight div 5); cvs := TDirect2DCanvas.Create(Canvas, ClientRect); cvs.BeginDraw; cvs.Brush.Style := bsClear; {原始} cvs.Pen.Color := clSilver; cvs.Pen.Width := 9; cvs.Polygon(pts); cvs.Pen.Width := 2; {平移} matrix := TD2DMatrix3x2F.Translation(90, 50); cvs.RenderTarget.SetTransform(matrix); cvs.Pen.Color := clRed; cvs.Polygon(pts); {放缩} matrix := TD2DMatrix3x2F.Scale(1.5, 0.5, pts[0]); cvs.RenderTarget.SetTransform(matrix); cvs.Pen.Color := clBlue; cvs.Polygon(pts); {旋转} matrix := TD2DMatrix3x2F.Rotation(90, pts[0]); // D2D1MakeRotateMatrix(90, pts[0], @matrix); //同上一行 cvs.RenderTarget.SetTransform(matrix); cvs.Pen.Color := clGreen; cvs.Polygon(pts); {斜切} matrix := TD2DMatrix3x2F.Skew(60, 0, pts[0]); // D2D1MakeSkewMatrix(60, 10, pts[0], @matrix); //同上一行 cvs.RenderTarget.SetTransform(matrix); cvs.Pen.Color := clPurple; cvs.Polygon(pts); cvs.EndDraw; cvs.Free; end; procedure TForm1.FormResize(Sender: TObject); begin Repaint; end;
效果图: