Direct2d (7): spatial transformation

{Related method} tdirect2dcanvas. rendertarget. settransform (); tdirect2dcanvas. rendertarget. gettransform (); {related structure} td2dmatrix3x2f (or d2d_matrix_3x2_f) // The value of the third column is fixed here (0, 0, 1 ), therefore, the 3*2 matrix is used here. This structure overload the * operator {td2dmatrix3x2fhelper is the method provided by td2dmatrix3x2f (mostly the class method)} identity (); // initialize td2dmatrix3x2f, default Value: _ 11, _ 22 is 1.0, and others are 0 translation (); // translation Scale (); // scale rotation (); // rotate skew (); // diagonal cut determinant (); // calculate the determinant isinvertible (); // whether it is reversible invert (); // reverse operation setproduct (); // multiply {related global functions} d2d1makerotatematrix (); // rotate d2d1makeskewmatrix (); // diagonal tangent trim (); // reversible d2d1invertmatrix (); // Inverse Operation
 

Test Code :

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; {Original} CVs. pen. color: = clsilver; CVs. pen. width: = 9; CVs. polygon (PTS); CVs. pen. width: = 2; {translation} matrix: = td2dmatrix3x2f. translation (90, 50); CVs. rendertarget. settransform (matrix); CVs. pen. color: = clred; CVs. polygon (PTS); {scale} matrix: = td2dmatrix3x2f. scale (1.5, 0.5, PTS [0]); CVs. rendertarget. settransform (matrix); CVs. pen. color: = clblue; CVs. polygon (PTS); {rotate} matrix: = td2dmatrix3x2f. rotation (90, PTS [0]); // d2d1makerotatematrix (90, PTS [0], @ matrix); // the same row as CVS. rendertarget. settransform (matrix); CVs. pen. color: = clgreen; CVs. polygon (PTS); {diagonal cut} matrix: = td2dmatrix3x2f. skew (60, 0, PTS [0]); // d2d1makeskewmatrix (60, 10, PTS [0], @ matrix); // the same row as CVS. rendertarget. settransform (matrix); CVs. pen. color: = clpurple; CVs. polygon (PTS); CVs. enddraw; CVs. free; end; Procedure tform1.formresize (Sender: tobject); begin repaint; end;

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