(module (s9fes char-canvas shape cross)

(;export
  cross-+-plotter cross-x-plotter)

(import scheme utf8)
(import (chicken base))
(import (chicken fixnum))
(import (chicken type))
(import (s9fes char-canvas))

(include-relative "s9fes.char-canvas.types")

(define-type shape-point-plotter (canvas #!optional fixnum fixnum -> void))

(: cross-+-plotter (fixnum #!optional fixnum (or false char plotter-configuration) -> shape-point-plotter))
(: cross-x-plotter (fixnum #!optional fixnum (or false char plotter-configuration) -> shape-point-plotter))

;;

(define (cross-+-plotter wd #!optional (ht wd) (cfg (current-plotter-char)))
  ;left & right bars
  (let* ((cfg (validate-plotter-configuration 'cross-+-plotter cfg 2))
         (mx (- wd 1)) (my (- ht 1))
         (c1 (car cfg)) (c2 (cadr cfg))
         (wd2 (/ wd 2)) (ht2 (/ ht 2)) )
    (lambda (cv #!optional (x0 0) (y0 0))
      (let ((xm (+ x0 wd2)) (ym (+ y0 ht2)))
        (when c1 (canvas-plot-line cv x0 ym (+ x0 mx) ym c1))
        (when c2 (canvas-plot-line cv xm (+ y0 my) xm y0 c2)) ) ) ) )

(define (cross-x-plotter wd #!optional (ht wd) (cfg (current-plotter-char)))
  ;left & right bars
  (let* ((cfg (validate-plotter-configuration 'cross-+-plotter cfg 2))
         (mx (- wd 1)) (my (- ht 1))
         (c1 (car cfg)) (c2 (cadr cfg)) )
    (lambda (cv #!optional (x0 0) (y0 0))
      (let ((x1 (+ x0 mx)) (y1 (+ y0 my)))
        (when c1 (canvas-plot-line cv x0 y1 x1 y0 c1))
        (when c2 (canvas-plot-line cv x0 y0 x1 y1 c2)) ) ) ) )

) ;module (s9fes char-canvas shape cross)