(* Copyright (c) 1993-1997, Silicon Graphics, Inc. * ALL RIGHTS RESERVED * Permission to use, copy, modify, and distribute this software for * any purpose and without fee is hereby granted, provided that the above * copyright notice appear in all copies and that both the copyright notice * and this permission notice appear in supporting documentation, and that * the name of Silicon Graphics, Inc. not be used in advertising * or publicity pertaining to distribution of the software without specific, * written prior permission. * * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU "AS-IS" * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE, * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT, * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION, * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE. * * US Government Users Restricted Rights * Use, duplication, or disclosure by the Government is subject to * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph * (c)(1)(ii) of the Rights in Technical Data and Computer Software * clause at DFARS 252.227-7013 and/or in similar or successor * clauses in the FAR or the DOD or NASA FAR Supplement. * Unpublished-- rights reserved under the copyright laws of the * United States. Contractor/manufacturer is Silicon Graphics, * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311. * * OpenGL(R) is a registered trademark of Silicon Graphics, Inc. *) (* unproject.ml * When the left mouse button is pressed, this program * reads the mouse position and determines two 3D points * from which it was transformed. Very little is displayed. *) (* Ported from C to OCaml by Florent Monnier *) open GL open Glu open Glut let display() = glClear [GL_COLOR_BUFFER_BIT]; glFlush(); ;; (* Change these values for a different transformation *) let reshape ~width:w ~height:h = glViewport 0 0 w h; glMatrixMode GL_PROJECTION; glLoadIdentity(); gluPerspective 45.0 (float w /. float h) 1.0 100.0; glMatrixMode GL_MODELVIEW; glLoadIdentity(); ;; let mouse ~button ~state ~x ~y = match button with | GLUT_LEFT_BUTTON -> if state = GLUT_DOWN then begin let viewport = glGetInteger4 Get.GL_VIEWPORT in let a, b, c, d = viewport in let viewport = [| a; b; c; d |] in let mvmatrix = glGetMatrix Get.GL_MODELVIEW_MATRIX in let projmatrix = glGetMatrix Get.GL_PROJECTION_MATRIX in (* note: viewport.(3) is height of window in pixels *) let realy = viewport.(3) - y - 1 in (* OpenGL y coordinate position *) Printf.printf "Coordinates at cursor are (%4d, %4d)\n%!" x realy; (* returned world x, y, z coords *) let wx, wy, wz = gluUnProject (float x) (float realy) 0.0 mvmatrix projmatrix viewport in Printf.printf "World coords at z=0.0 are (%f, %f, %f)\n%!" wx wy wz; let wx, wy, wz = gluUnProject (float x) (float realy) 1.0 mvmatrix projmatrix viewport in Printf.printf "World coords at z=1.0 are (%f, %f, %f)\n%!" wx wy wz; end | GLUT_RIGHT_BUTTON -> if state = GLUT_DOWN then exit(0); | _ -> () ;; let keyboard ~key ~x ~y = match key with | '\027' -> (*escape *) exit(0); | _ -> () ;; (* * Open window, register input callback functions *) let () = let _ = glutInit Sys.argv in glutInitDisplayMode [GLUT_SINGLE; GLUT_RGB]; glutInitWindowSize 500 500; glutInitWindowPosition 100 100; let _ = glutCreateWindow Sys.argv.(0) in glutDisplayFunc ~display; glutReshapeFunc ~reshape; glutKeyboardFunc ~keyboard; glutMouseFunc ~mouse; glutMainLoop(); ;;