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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* Unpublished-- rights reserved under the copyright laws of the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.
*/
/*
* picksquare.c
* Use of multiple names and picking are demonstrated.
* A 3x3 grid of squares is drawn. When the left mouse
* button is pressed, all squares under the cursor position
* have their color changed.
*/
#include <GL/gl.h>
#include <GL/glu.h>
#include <stdio.h>
#include <stdlib.h>
#include "glaux.h"
int board[3][3]; /* amount of color for each square */
/* Clear color value for every square on the board */
void myinit(void)
{
int i, j;
for (i = 0; i < 3; i++)
for (j = 0; j < 3; j ++)
board[i][j] = 0;
glClearColor (0.0, 0.0, 0.0, 0.0);
}
/* The nine squares are drawn. In selection mode, each
* square is given two names: one for the row and the
* other for the column on the grid. The color of each
* square is determined by its position on the grid, and
* the value in the board[][] array.
*/
void drawSquares(GLenum mode)
{
GLuint i, j;
for (i = 0; i < 3; i++) {
if (mode == GL_SELECT)
glLoadName (i);
for (j = 0; j < 3; j ++) {
if (mode == GL_SELECT)
glPushName (j);
glColor3f ((GLfloat) i/3.0, (GLfloat) j/3.0,
(GLfloat) board[i][j]/3.0);
glRecti (i, j, i+1, j+1);
if (mode == GL_SELECT)
glPopName ();
}
}
}
/* processHits() prints out the contents of the
* selection array.
*/
void processHits (GLint hits, GLuint buffer[])
{
unsigned int i, j;
GLuint ii, jj, names, *ptr;
printf ("hits = %d\n", hits);
ptr = (GLuint *) buffer;
for (i = 0; i < hits; i++) { /* for each hit */
names = *ptr;
printf (" number of names for this hit = %d\n", names); ptr++;
printf (" z1 is %u;", *ptr); ptr++;
printf (" z2 is %u\n", *ptr); ptr++;
printf (" names are ");
for (j = 0; j < names; j++) { /* for each name */
printf ("%d ", *ptr);
if (j == 0) /* set row and column */
ii = *ptr;
else if (j == 1)
jj = *ptr;
ptr++;
}
printf ("\n");
board[ii][jj] = (board[ii][jj] + 1) % 3;
}
}
/* pickSquares() sets up selection mode, name stack,
* and projection matrix for picking. Then the
* objects are drawn.
*/
#define BUFSIZE 512
void pickSquares(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 ();
/* create 5x5 pixel picking region near cursor location */
gluPickMatrix ((GLdouble) x, (GLdouble) (viewport[3] - y),
5.0, 5.0, viewport);
gluOrtho2D (0.0, 3.0, 0.0, 3.0);
drawSquares (GL_SELECT);
glMatrixMode (GL_PROJECTION);
glPopMatrix ();
glFlush ();
hits = glRenderMode (GL_RENDER);
processHits (hits, selectBuf);
}
void display(void)
{
glClear(GL_COLOR_BUFFER_BIT);
drawSquares (GL_RENDER);
glFlush();
}
void myReshape(int w, int h)
{
glViewport(0, 0, w, h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D (0.0, 3.0, 0.0, 3.0);
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, pickSquares);
auxReshapeFunc (myReshape);
auxMainLoop(display);
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.