;;;; This file is part of LilyPond, the GNU music typesetter.
;;;;
-;;;; Copyright (C) 2003--2010 Han-Wen Nienhuys <hanwen@xs4all.nl>
+;;;; Copyright (C) 2003--2011 Han-Wen Nienhuys <hanwen@xs4all.nl>
;;;;
;;;; LilyPond is free software: you can redistribute it and/or modify
;;;; it under the terms of the GNU General Public License as published by
(cons (min-max-crawler min cddr possible-extrema)
(min-max-crawler max cddr possible-extrema)))))
-(define-public
- (make-connected-shape-stencil pointlist
- thickness
- x-scale
- y-scale
- connect
- fill)
-
- (define (connected-shape-min-max pointlist)
-
- (define (line-part-min-max x1 x2)
- (list (min x1 x2) (max x1 x2)))
-
- (define (bezier-part-min-max x1 x2 x3 x4)
- ((lambda (x) (list (reduce min 10000 x) (reduce max -10000 x)))
- (map
- (lambda (x)
- (+ (* x1 (expt (- 1 x) 3))
- (+ (* 3 (* x2 (* (expt (- 1 x) 2) x)))
- (+ (* 3 (* x3 (* (- 1 x) (expt x 2))))
- (* x4 (expt x 3))))))
- (if (< (+ (expt x2 2) (+ (expt x3 2) (* x1 x4)))
- (+ (* x1 x3) (+ (* x2 x4) (* x2 x3))))
- (list 0.0 1.0)
- (filter
- (lambda (x) (and (>= x 0) (<= x 1)))
- (append
- (list 0.0 1.0)
- (map (lambda (op)
- (if (not (eqv? 0.0
- (- (+ x1 (* 3 x3)) (+ x4 (* 3 x2)))))
- ;; Zeros of the bezier curve
- (/ (+ (- x1 (* 2 x2))
- (op x3
- (sqrt (- (+ (expt x2 2)
- (+ (expt x3 2) (* x1 x4)))
- (+ (* x1 x3)
- (+ (* x2 x4) (* x2 x3)))))))
- (- (+ x1 (* 3 x3)) (+ x4 (* 3 x2))))
- ;; Apply L'hopital's rule to get the zeros if 0/0
- (* (op 0 1)
- (/ (/ (- x4 x3) 2)
- (sqrt (- (+ (* x2 x2)
- (+ (* x3 x3) (* x1 x4)))
- (+ (* x1 x3)
- (+ (* x2 x4) (* x2 x3)))))))))
- (list + -))))))))
+(define (path-min-max origin pointlist)
+
+ (define (line-part-min-max x1 x2)
+ (list (min x1 x2) (max x1 x2)))
+
+ (define (bezier-part-min-max x1 x2 x3 x4)
+ ((lambda (x) (list (reduce min 10000 x) (reduce max -10000 x)))
+ (map
+ (lambda (x)
+ (+ (* x1 (expt (- 1 x) 3))
+ (+ (* 3 (* x2 (* (expt (- 1 x) 2) x)))
+ (+ (* 3 (* x3 (* (- 1 x) (expt x 2))))
+ (* x4 (expt x 3))))))
+ (if (< (+ (expt x2 2) (+ (expt x3 2) (* x1 x4)))
+ (+ (* x1 x3) (+ (* x2 x4) (* x2 x3))))
+ (list 0.0 1.0)
+ (filter
+ (lambda (x) (and (>= x 0) (<= x 1)))
+ (append
+ (list 0.0 1.0)
+ (map (lambda (op)
+ (if (not (eqv? 0.0
+ (- (+ x1 (* 3 x3)) (+ x4 (* 3 x2)))))
+ ;; Zeros of the bezier curve
+ (/ (+ (- x1 (* 2 x2))
+ (op x3
+ (sqrt (- (+ (expt x2 2)
+ (+ (expt x3 2) (* x1 x4)))
+ (+ (* x1 x3)
+ (+ (* x2 x4) (* x2 x3)))))))
+ (- (+ x1 (* 3 x3)) (+ x4 (* 3 x2))))
+ ;; Apply L'hopital's rule to get the zeros if 0/0
+ (* (op 0 1)
+ (/ (/ (- x4 x3) 2)
+ (sqrt (- (+ (* x2 x2)
+ (+ (* x3 x3) (* x1 x4)))
+ (+ (* x1 x3)
+ (+ (* x2 x4) (* x2 x3)))))))))
+ (list + -))))))))
(define (bezier-min-max x1 y1 x2 y2 x3 y3 x4 y4)
(map (lambda (x)
- (apply bezier-part-min-max x))
- `((,x1 ,x2 ,x3 ,x4) (,y1 ,y2 ,y3 ,y4))))
+ (apply bezier-part-min-max x))
+ `((,x1 ,x2 ,x3 ,x4) (,y1 ,y2 ,y3 ,y4))))
(define (line-min-max x1 y1 x2 y2)
(map (lambda (x)
- (apply line-part-min-max x))
- `((,x1 ,x2) (,y1 ,y2))))
+ (apply line-part-min-max x))
+ `((,x1 ,x2) (,y1 ,y2))))
((lambda (x)
(list
(reduce min +inf.0 (map caadr x))
(reduce max -inf.0 (map cadadr x))))
(map (lambda (x)
- (if (eq? (length x) 8)
- (apply bezier-min-max x)
- (apply line-min-max x)))
- (map (lambda (x y)
- (append (list (cadr (reverse x)) (car (reverse x))) y))
- (append (list (list 0 0))
- (reverse (cdr (reverse pointlist)))) pointlist))))
-
- (let* ((boundlist (connected-shape-min-max pointlist)))
+ (if (eq? (length x) 8)
+ (apply bezier-min-max x)
+ (apply line-min-max x)))
+ (map (lambda (x y)
+ (append (list (cadr (reverse x)) (car (reverse x))) y))
+ (append (list origin)
+ (reverse (cdr (reverse pointlist)))) pointlist))))
+
+(define-public (make-connected-path-stencil pointlist thickness
+ x-scale y-scale connect fill)
+ "Make a connected path described by the list @var{pointlist}, with
+thickness @var{thickness}, and scaled by @var{x-scale} in the X direction
+and @var{y-scale} in the Y direction. @var{connect} and @var{fill} are
+boolean arguments that specify if the path should be connected or filled,
+respectively."
+
+ ;; paths using this routine are designed to begin at point '(0 . 0)
+ (let* ((origin (list 0 0))
+ (boundlist (path-min-max origin pointlist))
+ ;; modify pointlist to scale the coordinates
+ (path (map (lambda (x)
+ (apply
+ (if (eq? 6 (length x))
+ (lambda (x1 x2 x3 x4 x5 x6)
+ (list 'curveto
+ (* x1 x-scale)
+ (* x2 y-scale)
+ (* x3 x-scale)
+ (* x4 y-scale)
+ (* x5 x-scale)
+ (* x6 y-scale)))
+ (lambda (x1 x2)
+ (list 'lineto
+ (* x1 x-scale)
+ (* x2 y-scale))))
+ x))
+ pointlist))
+ ;; a path must begin with a `moveto'
+ (prepend-origin (apply list (cons 'moveto origin) path))
+ ;; if this path is connected, add closepath to the end
+ (final-path (if connect
+ (append prepend-origin (list 'closepath))
+ prepend-origin))
+ (command-list (fold-right append '() final-path)))
+
(ly:make-stencil
- `(connected-shape
- ',pointlist
- ',thickness
- ',x-scale
- ',y-scale
- ',connect
- ',fill)
+ `(path ,thickness
+ `(,@',command-list)
+ 'round
+ 'round
+ ,(if fill #t #f))
(coord-translate
((if (< x-scale 0) reverse-interval identity)
(cons (* x-scale (list-ref boundlist 0))
projects / lilypond.git / blobdiff