Page 41	Table of Contents	Index	Page 43
	Chapters
	1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 A, B, C, D, E

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CHAPTER 5. AFFINE TRANSFORMATIONS

=> transform-distance transformation dx dy [Generic Function]
Applies the transformation transformation to the distance represented by the real numbers dx
and dy, and returns two values, the transformed dx and the transformed dy.

A distance represents the difference between two points. It does not transform like a point.

=> untransform-distance transformation dx dy [Generic Function]
This is exactly equivalent to
(transform-distance (invert-transformation transformation) dx dy) .

CLIM provides a default method for untransform-distance on the transformation protocol
class that does exactly this.

=> transform-rectangle* transformation x1 y1 x2 y2 [Generic Function]
Applies the transformation transformation to the rectangle specified by the four coordinate
arguments, which are real numbers. The arguments x1, y1, x2, and y1 are canonicalized in the
same way as for make-bounding-rectangle. Returns four values that specify the minimum and
maximum points of the transformed rectangle in the order min-x, min-y, max-x, and max-y.

It is an error is transformation does not satisfy rectilinear-transformation-p.

transform-rectangle* is the spread version of transform-region in the case where the trans-
formation is rectilinear and the region is a rectangle.

=> untransform-rectangle* transformation x1 y1 x2 y2 [Generic Function]
This is exactly equivalent to
(transform-rectangle* (invert-transformation transformation) x1 y1 x2 y2) .

CLIM provides a default method for untransform-rectangle* on the transformation protocol
class that does exactly this.

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Page 41	Table of Contents	Index	Page 43
	Chapters
	1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 A, B, C, D, E