Examples/addhandrotate.lsp

   1 ;; add a new "mouse mode", with menu title, cusror and mouse method name
   2 (send spin-proto :add-mouse-mode 'hand-rotate
   3       :title "Hand Rotate" :cursor 'hand :click :do-hand-rotate)
   4
   5 ;; set up local environment with function to project (x, y) point onto
   6 ;; "globe" overthe plot
   7 (flet ((calcsphere (x y)
   8         (let* ((norm-2 (+ (* x x) (* y y)))
   9                (rad-2 (^ 1.7 2))
  10                (z (if (< norm-2 rad-2) (sqrt (- rad-2 norm-2)) 0)))
  11           (if (< norm-2 rad-2)
  12               (list x y z)
  13               (let ((r (sqrt (max norm-2 rad-2))))
  14                 (list (/ x r) (/ y r) (/ z r)))))))
  15
  16   ;; define the :DO-HAND-ROTATE method in the local environment
  17   (defmeth spin-proto :do-hand-rotate (x y m1 m2)
  18     (let* ((oldp (apply #'calcsphere
  19                         (send self :canvas-to-scaled x y)))
  20            (p oldp)
  21            (vars (send self :content-variables))
  22            (trans (identity-matrix (send self :num-variables))))
  23       (send self :idle-on nil)
  24       (send self :while-button-down
  25             #'(lambda (x y)
  26                 (setf oldp p)
  27                 (setf p (apply #'calcsphere
  28                                (send self :canvas-to-scaled x y)))
  29                 (setf (select trans vars vars) (make-rotation oldp p))
  30                 (when m1
  31                       (send self :slot-value 'rotation-type trans)
  32                       (send self :idle-on t))
  33                 (send self
  34                       :apply-transformation
  35                       trans))))))
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