Author: tpapp Date: Tue Aug 14 03:53:12 2007 New Revision: 12

Modified: transformations.lisp tutorial/ (props changed) tutorial/example.lisp tutorial/tutorial.tex Log: minor fixes in transformations code

Modified: transformations.lisp ============================================================================== --- transformations.lisp (original) +++ transformations.lisp Tue Aug 14 03:53:12 2007 @@ -5,13 +5,16 @@ ;;;; cairo-matrix-init is not defined, as we have a structure in lisp ;;;; with an appropriate constructor ;;;; -;;;; cairo_identity_matrix is reset-matrix +;;;; cairo_identity_matrix is reset-trans-matrix ;;;; ;;;; functions that manipulate transformation matrices have ;;;; trans-matrix instead of matrix in their name ;;;; ;;;; cairo_matrix_transform_distance and cairo_matrix_transform_point ;;;; are simply transform-distance and transform-point +;;;; +;;;; cairo_matrix_init is not defined, make-trans-matrix will give +;;;; you an identity matrix

;;;; ;;;; simple functions @@ -22,7 +25,7 @@ (scale sx sy) (rotate angle))

-(define-flexible (reset-matrix pointer) +(define-flexible (reset-trans-matrix pointer) (cairo_identity_matrix pointer))

@@ -30,7 +33,13 @@ ;;;; transition matrix structure and helper functions/macros ;;;;

-(defstruct trans-matrix xx yx xy yy x0 y0) +(defstruct trans-matrix + (xx 1d0 :type double-float) + (yx 0d0 :type double-float) + (xy 0d0 :type double-float) + (yy 1d0 :type double-float) + (x0 0d0 :type double-float) + (y0 0d0 :type double-float))

(defun trans-matrix-copy-in (pointer matrix) "Copy matrix to a memory location." @@ -108,7 +117,7 @@

(define-flexible (get-trans-matrix pointer) (with-trans-matrix-out matrix-pointer - (cairo_set_matrix pointer matrix-pointer))) + (cairo_get_matrix pointer matrix-pointer)))

(define-with-x-y user-to-device) (define-with-x-y user-to-device-distance) @@ -129,7 +138,6 @@ matrix-pointer ,@args)))))

-(define-matrix-init identity) (define-matrix-init translate tx ty) (define-matrix-init scale sx sy) (define-matrix-init rotate radians)

Modified: tutorial/example.lisp ============================================================================== --- tutorial/example.lisp (original) +++ tutorial/example.lisp Tue Aug 14 03:53:12 2007 @@ -167,7 +167,7 @@ ;; draw the hearts (dotimes (i 200) (let ((scaling (+ 5d0 (random 40d0)))) - (reset-matrix) ; reset matrix + (reset-trans-matrix) ; reset matrix (translate (random width) (random height)) ; move the origin (scale scaling scaling) ; scale (rotate (deg-to-rad (- (random (* 2 max-angle)) max-angle 180))) ; rotate

Modified: tutorial/tutorial.tex ============================================================================== --- tutorial/tutorial.tex (original) +++ tutorial/tutorial.tex Tue Aug 14 03:53:12 2007 @@ -189,7 +189,8 @@ \verb!cairo_fill! (would conflict with \lstinline!cl:fill!) & \lstinline!fill-path! \ \verb!cairo_identity_matrix! (would - conflict with matrix algebra packages)& \lstinline!reset-matrix! \ + conflict with matrix algebra packages)& \lstinline!reset-trans-matrix! \ + \verb!cairo_matrix_init_identity! & use \lstinline!(make-trans-matrix)!\ \verb!cairo_matrix_transform_distance! & \lstinline!transform-distance!\ \verb!cairo_matrix_transform_point! & @@ -320,10 +321,12 @@

cl-cairo2 defines the structure \lstinline!trans-matrix! with the slots \lstinline!xx!, \lstinline!yx!, \lstinline!xy!, \lstinline!yy!, -\lstinline!x0!, \lstinline!y0!. All the functions that use -transformation matrices use this structure. Consequently, -\verb!cairo_matrix_init! has no corresponding function in cl-cairo2: -you can construct a translation matrix using +\lstinline!x0!, \lstinline!y0!. The defaults for these slots give you +the identity matrix. + +All the functions that use transformation matrices use this structure. +Consequently, \verb!cairo_matrix_init! has no corresponding function +in cl-cairo2: you can construct a translation matrix using \lstinline!make-trans-matrix!.

Some functions are renamed, see Table~\ref{tab:naming}. Generally,