;;;; Programmer: Kevin M. Rosenberg
;;;; Date Started: April 2005
;;;;
-;;;; $Id: package.lisp 8596 2004-02-03 18:32:50Z kevin $
+;;;; $Id$
;;;;
-;;;; This file, part of cl-photo, is Copyright (c) 2005 by Kevin Rosenberg.
-;;;; Rights of modification and redistribution are in the LICENSE file.
+;;;; This file, part of cl-photo, is Copyright (c) 2005 by Kevin M. Rosenberg
+;;;;
+;;;; cl-photo users are granted the rights to distribute and use this software
+;;;; as governed by the terms of the GNU General Public License v2
+;;;; (http://www.gnu.org/licenses/gpl.html)
;;;;
;;;; *************************************************************************
(in-package #:photo)
(defconstant +radian->degrees+ (/ 360d0 pi 2))
-(defconstant +inches->mm+ 25.4)
+(defconstant +inches->mm+ 25.4d0)
+(declaim (inline diagonal))
(defun diagonal (x y)
(sqrt (+ (* x x) (* y y))))
+(declaim (inline radians->degrees))
(defun radians->degrees (r)
(* +radian->degrees+ r))
+(declaim (inline degrees->radians))
+(defun degrees->radians (r)
+ (/ r +radian->degrees+))
+
+(declaim (inline mm->feet))
(defun mm->feet (d)
(/ d +inches->mm+ 12))
+(declaim (inline feet->mm))
(defun feet->mm (d)
(* d 12 +inches->mm+))
+(declaim (inline inches->mm))
+(defun inches->mm (d)
+ (* d +inches->mm+))
+
+(declaim (inline mm->inches))
+(defun mm->inches (d)
+ (/ d +inches->mm+))
+
+(defun length->mm (d units)
+ "Convert a length in units to mm."
+ (ecase units
+ (:mm d)
+ (:inches (inches->mm d))
+ (:feet (inches->mm (* d 12)))
+ (:yards (inches->mm (* d 36)))
+ (:meters (* 1000 d))))
+
+(defun mm->length (d units)
+ "Convert a number of mm to units."
+ (ecase units
+ (:mm d)
+ (:inches (mm->inches d))
+ (:feet (/ (mm->inches d) 12))
+ (:yards (/ (mm->inches d) 36))
+ (:meters (/ d 1000))))
+
+