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/*
* Copyright (c) 1991, 1992, 1993 Silicon Graphics, Inc.
*
* Permission to use, copy, modify, distribute, and sell this software and
* its documentation for any purpose is hereby granted without fee, provided
* that (i) the above copyright notices and this permission notice appear in
* all copies of the software and related documentation, and (ii) the name of
* Silicon Graphics may not be used in any advertising or
* publicity relating to the software without the specific, prior written
* permission of Silicon Graphics.
*
* THE SOFTWARE IS PROVIDED "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 BE LIABLE FOR
* ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
* OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
* WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
* LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
* OF THIS SOFTWARE.
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <GL/glut.h>
GLenum doubleBuffer = 1;
int win;
static float tx = 0;
static float ty = 0;
static float tw = 250;
static float th = 250;
static void Init(void)
{
fprintf(stderr, "GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
fprintf(stderr, "GL_VERSION = %s\n", (char *) glGetString(GL_VERSION));
fprintf(stderr, "GL_VENDOR = %s\n", (char *) glGetString(GL_VENDOR));
fflush(stderr);
glClearColor(0.3, 0.1, 0.3, 0.0);
}
static void Reshape(int width, int height)
{
tw = width;
th = height;
}
static void Key(unsigned char key, int x, int y)
{
switch (key) {
case 27:
exit(0);
default:
glutPostRedisplay();
return;
}
}
static void Draw(void)
{
int i;
fprintf(stderr, "%f %f\n", tx, ty);
fflush(stderr);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
glMatrixMode(GL_MODELVIEW);
glClear(GL_COLOR_BUFFER_BIT);
glViewport(0, 0, tw, th);
glBegin(GL_LINES);
glColor3f(1,1,0);
glVertex3f(-1, 0, -30.0);
glVertex3f(1, 0, -30.0);
glVertex3f(0, -1, -30.0);
glVertex3f(0, 1, -30.0);
glEnd();
/*
*/
glViewport(tx, ty, tw, th);
glBegin(GL_TRIANGLES);
glColor3f(1,0,0);
glVertex3f(-1, -1, -30.0);
glVertex3f(0, -1, -30.0);
glVertex3f(-.5, -.5, -30.0);
glColor3f(1,1,1);
glVertex3f(0, -1, -30.0);
glVertex3f(1, -1, -30.0);
glVertex3f(.5, -.5, -30.0);
glVertex3f(-.5, -.5, -30.0);
glVertex3f(.5, -.5, -30.0);
glVertex3f(0, 0, -30.0);
glColor3f(0,1,0);
glVertex3f(1, 1, -30.0);
glVertex3f(0, 1, -30.0);
glVertex3f(.5, .5, -30.0);
glColor3f(1,1,1);
glVertex3f(0, 1, -30.0);
glVertex3f(-1, 1, -30.0);
glVertex3f(-.5, .5, -30.0);
glVertex3f(.5, .5, -30.0);
glVertex3f(-.5, .5, -30.0);
glVertex3f( 0, 0, -30.0);
glEnd();
glViewport(0, 0, tw, th);
glBegin(GL_LINES);
glColor3f(.5,.5,0);
for (i = -10; i < 10; i++) {
float f = i / 10.0;
if (i == 0)
continue;
glVertex3f(-1, f, -30.0);
glVertex3f(1, f, -30.0);
glVertex3f(f, -1, -30.0);
glVertex3f(f, 1, -30.0);
}
glEnd();
glFlush();
if (doubleBuffer) {
glutSwapBuffers();
}
}
static GLenum Args(int argc, char **argv)
{
GLint i;
if (getenv("VPX"))
tx = atof(getenv("VPX"));
if (getenv("VPY"))
ty = atof(getenv("VPY"));
for (i = 1; i < argc; i++) {
if (strcmp(argv[i], "-sb") == 0) {
doubleBuffer = GL_FALSE;
} else if (strcmp(argv[i], "-db") == 0) {
doubleBuffer = GL_TRUE;
} else {
fprintf(stderr, "%s (Bad option).\n", argv[i]);
return GL_FALSE;
}
}
return GL_TRUE;
}
static void
special(int k, int x, int y)
{
switch (k) {
case GLUT_KEY_UP:
ty += 1.0;
break;
case GLUT_KEY_DOWN:
ty -= 1.0;
break;
case GLUT_KEY_LEFT:
tx -= 1.0;
break;
case GLUT_KEY_RIGHT:
tx += 1.0;
break;
default:
return;
}
glutPostRedisplay();
}
int main(int argc, char **argv)
{
GLenum type;
glutInit(&argc, argv);
if (Args(argc, argv) == GL_FALSE) {
exit(1);
}
glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
type = GLUT_RGB | GLUT_ALPHA;
type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
glutInitDisplayMode(type);
win = glutCreateWindow(*argv);
if (!win) {
exit(1);
}
Init();
glutReshapeFunc(Reshape);
glutKeyboardFunc(Key);
glutSpecialFunc(special);
glutDisplayFunc(Draw);
glutMainLoop();
return 0;
}
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