127 lines
4.3 KiB
C
127 lines
4.3 KiB
C
/*
|
|
* 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* Unpublished-- rights reserved under the copyright laws of the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.c
|
|
* 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.
|
|
*/
|
|
#include <GL/glut.h>
|
|
#include <stdlib.h>
|
|
#include <stdio.h>
|
|
|
|
void display(void)
|
|
{
|
|
glClear(GL_COLOR_BUFFER_BIT);
|
|
glFlush();
|
|
}
|
|
|
|
/* Change these values for a different transformation */
|
|
void reshape(int w, int h)
|
|
{
|
|
glViewport (0, 0, (GLsizei) w, (GLsizei) h);
|
|
glMatrixMode(GL_PROJECTION);
|
|
glLoadIdentity();
|
|
gluPerspective (45.0, (GLfloat) w/(GLfloat) h, 1.0, 100.0);
|
|
glMatrixMode(GL_MODELVIEW);
|
|
glLoadIdentity();
|
|
}
|
|
|
|
void mouse(int button, int state, int x, int y)
|
|
{
|
|
GLint viewport[4];
|
|
GLdouble mvmatrix[16], projmatrix[16];
|
|
GLint realy; /* OpenGL y coordinate position */
|
|
GLdouble wx, wy, wz; /* returned world x, y, z coords */
|
|
|
|
switch (button) {
|
|
case GLUT_LEFT_BUTTON:
|
|
if (state == GLUT_DOWN) {
|
|
glGetIntegerv (GL_VIEWPORT, viewport);
|
|
glGetDoublev (GL_MODELVIEW_MATRIX, mvmatrix);
|
|
glGetDoublev (GL_PROJECTION_MATRIX, projmatrix);
|
|
/* note viewport[3] is height of window in pixels */
|
|
realy = viewport[3] - (GLint) y - 1;
|
|
printf ("Coordinates at cursor are (%4d, %4d)\n", x, realy);
|
|
gluUnProject ((GLdouble) x, (GLdouble) realy, 0.0,
|
|
mvmatrix, projmatrix, viewport, &wx, &wy, &wz);
|
|
printf ("World coords at z=0.0 are (%f, %f, %f)\n",
|
|
wx, wy, wz);
|
|
gluUnProject ((GLdouble) x, (GLdouble) realy, 1.0,
|
|
mvmatrix, projmatrix, viewport, &wx, &wy, &wz);
|
|
printf ("World coords at z=1.0 are (%f, %f, %f)\n",
|
|
wx, wy, wz);
|
|
}
|
|
break;
|
|
case GLUT_RIGHT_BUTTON:
|
|
if (state == GLUT_DOWN)
|
|
exit(0);
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* ARGSUSED1 */
|
|
void keyboard(unsigned char key, int x, int y)
|
|
{
|
|
switch (key) {
|
|
case 27:
|
|
exit(0);
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Open window, register input callback functions
|
|
*/
|
|
int main(int argc, char** argv)
|
|
{
|
|
glutInit(&argc, argv);
|
|
glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);
|
|
glutInitWindowSize (500, 500);
|
|
glutInitWindowPosition (100, 100);
|
|
glutCreateWindow (argv[0]);
|
|
glutDisplayFunc(display);
|
|
glutReshapeFunc(reshape);
|
|
glutKeyboardFunc (keyboard);
|
|
glutMouseFunc(mouse);
|
|
glutMainLoop();
|
|
return 0;
|
|
}
|