This is feedback.c in view mode; [Download] [Up]
/*
* (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* Unpublished-- rights reserved under the copyright laws of the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.
*/
/*
* feedback.c
* This program demonstrates use of OpenGL feedback. First,
* a lighting environment is set up and a few lines are drawn.
* Then feedback mode is entered, and the same lines are
* drawn. The results in the feedback buffer are printed.
*/
#include <GL/gl.h>
#include <GL/glu.h>
#include <stdio.h>
#include <stdlib.h>
#include "glaux.h"
/* Initialize lighting.
*/
void myinit(void)
{
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
}
/* Draw a few lines and two points, one of which will
* be clipped. If in feedback mode, a passthrough token
* is issued between the each primitive.
*/
void drawGeometry (GLenum mode)
{
glBegin (GL_LINE_STRIP);
glNormal3f (0.0, 0.0, 1.0);
glVertex3f (30.0, 30.0, 0.0);
glVertex3f (50.0, 60.0, 0.0);
glVertex3f (70.0, 40.0, 0.0);
glEnd ();
if (mode == GL_FEEDBACK)
glPassThrough (1.0);
glBegin (GL_POINTS);
glVertex3f (-100.0, -100.0, -100.0); /* will be clipped */
glEnd ();
if (mode == GL_FEEDBACK)
glPassThrough (2.0);
glBegin (GL_POINTS);
glNormal3f (0.0, 0.0, 1.0);
glVertex3f (50.0, 50.0, 0.0);
glEnd ();
}
/* Write contents of one vertex to stdout. */
void print3DcolorVertex (GLint size,
GLint *count, GLfloat *buffer)
{
int i;
printf (" ");
for (i = 0; i < 7; i++) {
printf ("%4.2f ", buffer[size-(*count)]);
*count = *count - 1;
}
printf ("\n");
}
/* Write contents of entire buffer. (Parse tokens!) */
void printBuffer(GLint size, GLfloat *buffer)
{
GLint count;
GLfloat token;
count = size;
while (count) {
token = buffer[size-count]; count--;
if (token == GL_PASS_THROUGH_TOKEN) {
printf ("GL_PASS_THROUGH_TOKEN\n");
printf (" %4.2f\n", buffer[size-count]);
count--;
}
else if (token == GL_POINT_TOKEN) {
printf ("GL_POINT_TOKEN\n");
print3DcolorVertex (size, &count, buffer);
}
else if (token == GL_LINE_TOKEN) {
printf ("GL_LINE_TOKEN\n");
print3DcolorVertex (size, &count, buffer);
print3DcolorVertex (size, &count, buffer);
}
else if (token == GL_LINE_RESET_TOKEN) {
printf ("GL_LINE_RESET_TOKEN\n");
print3DcolorVertex (size, &count, buffer);
print3DcolorVertex (size, &count, buffer);
}
}
}
void display(void)
{
GLfloat feedBuffer[1024];
GLint size;
glMatrixMode (GL_PROJECTION);
glLoadIdentity ();
glOrtho (0.0, 100.0, 0.0, 100.0, 0.0, 1.0);
glClearColor (0.0, 0.0, 0.0, 0.0);
glClear(GL_COLOR_BUFFER_BIT);
drawGeometry (GL_RENDER);
glFeedbackBuffer (1024, GL_3D_COLOR, feedBuffer);
(void) glRenderMode (GL_FEEDBACK);
drawGeometry (GL_FEEDBACK);
size = glRenderMode (GL_RENDER);
printBuffer (size, feedBuffer);
}
/* 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 ();
auxMainLoop(display);
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.