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currentmatrix () typedict.Matrix

Returns a copy of this matrix. The result is always writable, which means currentmatrix is an easy way to make a copy of a read-only matrix, like `VM.screen.defaultmatrix`, that can be modified by your program.

currentmatrix and setmatrix are sometimes used in pairs when an application describes a path in a coordinate system that has been scaled or sheared, but wants to stroke the outline of that path in a way that hides the changes that were made to the coordinate system.

Incidentally, one very common use of currentmatrix and setmatrix in PostScript, namely drawing the outline of an ellipse, can usually be handled more efficiently by passing horizontal and vertical scaling arguments directly to the arc drawing built-ins defined in Graphics and Path.
 Example: The program, ```import yoix.*.*; JFrame f = { Color background = Color.white; Graphics graphics = { int linewidth = 72/4; int antialiasing = TRUE; }; paint(Rectangle rect) { Matrix mtx; int n; graphics { // "named block" gsave(); rectclip(rect); translate(size.width/2, size.height/2); mtx = currentmatrix(); rotate(atan2(size.height, size.width)*180.0/PI); scale(2, .5); arc(0, 0, 1.5*72, 0, 360); gsave(); // save the path setrgbcolor(0, 1, 0); fill(.3); grestore(); setrgbcolor(1, 0, 0); stroke(.5); setmatrix(mtx); // too late grestore(); } } }; f.visible = TRUE; ```defines a paint function in a frame that fills and outlines an ellipse that is placed at the center of the frame with its major axis on the line that connects the frame's upper left and lower right corners. The fractional arguments used when we fill and stroke the path are alpha values that let part of the background show through. We wanted the outline to be drawn in a uniform thickness, so we used currentmatrix and setmatrix, but our setmatrix call was too late. See if you can figure out where it really belongs. Return: Matrix See Also: concat, concatmatrix, dividematrix, dtransform, Graphics, identmatrix, idtransform, initmatrix, invertmatrix, itransform, maptopixel, rotate, scale, setmatrix, shear, transform, translate

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