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/*
* (c) Copyright 1993, 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* Unpublished-- rights reserved under the copyright laws of the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(TM) is a trademark of Silicon Graphics, Inc.
*/
/*
* pickline.c
* Picking is demonstrated here. Press the left mouse button
* is enter picking mode. You get two hits if you press the
* mouse, while the cursor is where the lines intersect.
*/
#include <GL/gl.h>
#include <GL/glu.h>
#include <stdio.h>
#include <stdlib.h>
#include "glaux.h"
void drawLine(GLenum mode)
{
if (mode == GL_SELECT)
glLoadName (1);
glBegin (GL_LINES);
glColor3f (1.0, 1.0, 1.0);
glVertex3f (30.0, 30.0, 0.0);
glVertex3f (50.0, 60.0, 0.0);
glEnd ();
if (mode == GL_SELECT)
glLoadName (2);
glBegin (GL_LINES);
glColor3f (1.0, 1.0, 1.0);
glVertex3f (50.0, 60.0, 0.0);
glVertex3f (70.0, 40.0, 0.0);
glEnd ();
}
/* pickline() is called when the mouse is pressed.
* The projection matrix is reloaded to include the
* picking matrix. The line is "redrawn" during
* selection mode, and names are sent to the buffer.
*/
#define BUFSIZE 512
void pickLine(AUX_EVENTREC *event)
{
GLuint selectBuf[BUFSIZE];
GLint hits;
GLint viewport[4];
int x, y;
x = event->data[AUX_MOUSEX];
y = event->data[AUX_MOUSEY];
glGetIntegerv (GL_VIEWPORT, viewport);
glSelectBuffer (BUFSIZE, selectBuf);
(void) glRenderMode (GL_SELECT);
glInitNames();
glPushName(-1);
glMatrixMode (GL_PROJECTION);
glPushMatrix ();
glLoadIdentity ();
gluPickMatrix ((GLdouble) x, (GLdouble) (viewport[3] - y),
5.0, 5.0, viewport);
gluOrtho2D (0.0, (GLdouble) viewport[2],
0.0, (GLdouble) viewport[3]);
drawLine (GL_SELECT);
glPopMatrix ();
glFlush ();
hits = glRenderMode (GL_RENDER);
printf ("hits is %d\n", hits);
}
void myinit (void)
{
glShadeModel (GL_FLAT);
glClearColor (0.0, 0.0, 0.0, 0.0);
}
void display(void)
{
glClear(GL_COLOR_BUFFER_BIT);
drawLine (GL_RENDER);
glFlush();
}
void myReshape(int w, int h)
{
glViewport(0, 0, w, h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D (0.0, (GLdouble) w, 0.0, (GLdouble) h);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
}
/* Main Loop
* Open window with initial window size, title bar,
* RGBA display mode, and handle input events.
*/
int main(int argc, char** argv)
{
auxInitDisplayMode (AUX_SINGLE | AUX_RGB);
auxInitPosition (0, 0, 100, 100);
auxInitWindow (argv[0]);
myinit ();
auxMouseFunc (AUX_LEFTBUTTON, AUX_MOUSEDOWN, pickLine);
auxReshapeFunc (myReshape);
auxMainLoop(display);
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.