(fov-one-dim focal-length (diagonal frame-width frame-height)
:projection projection)))
+(defun fov-distance (focal-length frame-width frame-height distance
+ &key (projection :rectilinear))
+ "Returns the field of view and image magnificaion ratio at a given distance.
+NOTE: magnification assumes that distance is in the same units as frame size: mm"
+ (multiple-value-bind (fov-width fov-height fov-diagonal)
+ (fov focal-length frame-width frame-height :projection projection)
+ (let* ((d-width (* distance (sin (degrees->radians fov-width))))
+ (d-height (* distance (sin (degrees->radians fov-height))))
+ (d-diagonal (* distance (sin (degrees->radians fov-diagonal))))
+ (mag (/ frame-width d-width)))
+ (values d-width d-height d-diagonal mag))))
+
(defun fov-format (focal-length format &key (projection :rectilinear))
"Returns the angle of field of view for a focal length and frame size at infinity"
- (ecase format
- (:aps-c
- (fov focal-length 22.7 15.1 :projection projection))
- (:aps
- (fov focal-length 24 18 :projection projection))
- (:35mm
- (fov focal-length 36 24 :projection projection))
- (:4.5x6
- (fov focal-length 45 60 :projection projection))
- (:6x6
- (fov focal-length 60 60 :projection projection))
- (:6x7
- (fov focal-length 60 70 :projection projection))
- (:6x9
- (fov focal-length 60 90 :projection projection))
- (:4x5
- (fov focal-length (* 4 +inches->mm+) (* 5 +inches->mm+)
- :projection projection))
- (:8x10
- (fov focal-length (* 8 +inches->mm+) (* 10 +inches->mm+)
- :projection projection))
- ))
-
+ (let ((dim (format-dimensions format)))
+ (fov focal-length (car dim) (cdr dim) :projection projection)))
projects / cl-photo.git / blobdiff