diff options
Diffstat (limited to 'pnm/pgm.scm')
| -rw-r--r-- | pnm/pgm.scm | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/pnm/pgm.scm b/pnm/pgm.scm index c37d587..200720f 100644 --- a/pnm/pgm.scm +++ b/pnm/pgm.scm @@ -45,29 +45,29 @@ (if (< maxval 256) (let ((byte-count (* width height))) (define (xy->idx x y) (+ x (* y width))) - (define (pixel-reader x y) + (define (pixel-getter x y) (let ((idx (xy->idx x y))) (bytevector-u8-ref data idx))) - (define (pixel-writer x y v) + (define (pixel-setter x y v) (let ((idx (xy->idx x y))) (bytevector-u8-set! data idx v))) (unless (= byte-count (bytevector-length data)) (error (string-append "(pnm pbm) make-pbm-image: Invalid bytevector length" byte-count))) - (make-image 'pgm width height maxval data pixel-reader pixel-writer)) + (make-image 'pgm width height maxval data pixel-getter pixel-setter)) (let ((byte-count (* width height 2))) (define (xy->idx x y) (+ x (* y width))) - (define (pixel-reader x y) + (define (pixel-getter x y) (let ((idx (xy->idx x y))) (combine-values (bytevector-u8-ref data idx) (bytevector-u8-ref data (+ idx 1))))) - (define (pixel-writer x y v) + (define (pixel-setter x y v) (let ((idx (xy->idx x y))) (let-values (((v1 v2) (split-value v))) (bytevector-u8-set! data idx v1) (bytevector-u8-set! data (+ idx 1) v2)))) (unless (= byte-count (bytevector-length data)) (error (string-append "(pnm pbm) make-pbm-image: Invalid bytevector length" byte-count))) - (make-image 'pgm width height maxval data pixel-reader pixel-writer)))) + (make-image 'pgm width height maxval data pixel-getter pixel-setter)))) (define (split-value v) (values (modulo (quotient v 256) 256) |