328 lines
6.5 KiB
C
328 lines
6.5 KiB
C
/*
|
|
* 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 = 0;
|
|
static float th = 0;
|
|
static float z = -5;
|
|
|
|
|
|
static float win_width = 250;
|
|
static float win_height = 250;
|
|
static enum {
|
|
ORTHO,
|
|
FRUSTUM,
|
|
MODE_MAX
|
|
} mode = ORTHO;
|
|
|
|
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, 0, 0, 0.0);
|
|
}
|
|
|
|
static void Reshape(int width, int height)
|
|
{
|
|
win_width = width;
|
|
win_height = height;
|
|
glutPostRedisplay();
|
|
}
|
|
|
|
|
|
static void Key(unsigned char key, int x, int y)
|
|
{
|
|
switch (key) {
|
|
case 27:
|
|
exit(0);
|
|
case 'w':
|
|
tw += 1.0;
|
|
break;
|
|
case 'W':
|
|
tw -= 1.0;
|
|
break;
|
|
case 'h':
|
|
th += 1.0;
|
|
break;
|
|
case 'H':
|
|
th -= 1.0;
|
|
break;
|
|
|
|
case 'z':
|
|
z += 1.0;
|
|
break;
|
|
case 'Z':
|
|
z -= 1.0;
|
|
break;
|
|
case 'm':
|
|
mode++;
|
|
mode %= MODE_MAX;
|
|
break;
|
|
case ' ':
|
|
tw = th = tx = ty = 0;
|
|
z = -5;
|
|
mode = ORTHO;
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
glutPostRedisplay();
|
|
}
|
|
|
|
|
|
static void Draw(void)
|
|
{
|
|
int i;
|
|
float w = tw + win_width;
|
|
float h = th + win_height;
|
|
|
|
fprintf(stderr, "glViewport(%f %f %f %f)\n", tx, ty, w, h);
|
|
fprintf(stderr, "mode: %s\n", mode == FRUSTUM ? "FRUSTUM" : "ORTHO");
|
|
fprintf(stderr, "z: %f\n", z);
|
|
fflush(stderr);
|
|
|
|
glMatrixMode(GL_PROJECTION);
|
|
glLoadIdentity();
|
|
|
|
switch (mode) {
|
|
case FRUSTUM:
|
|
glFrustum(-1.0, 1.0, -1.0, 1.0, 5.0, 25.0);
|
|
break;
|
|
case ORTHO:
|
|
default:
|
|
glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
|
|
break;
|
|
}
|
|
|
|
glMatrixMode(GL_MODELVIEW);
|
|
glLoadIdentity();
|
|
|
|
|
|
glClear(GL_COLOR_BUFFER_BIT);
|
|
|
|
|
|
/***********************************************************************
|
|
* Should be clipped to be no larger than the triangles:
|
|
*/
|
|
glViewport(tx, ty, w, h);
|
|
|
|
glBegin(GL_POLYGON);
|
|
glColor3f(1,1,0);
|
|
glVertex3f(-100, -100, z);
|
|
glVertex3f(-100, 100, z);
|
|
glVertex3f(100, 100, z);
|
|
glVertex3f(100, -100, z);
|
|
glEnd();
|
|
|
|
glBegin(GL_POLYGON);
|
|
glColor3f(0,1,1);
|
|
glVertex3f(-10, -10, z);
|
|
glVertex3f(-10, 10, z);
|
|
glVertex3f(10, 10, z);
|
|
glVertex3f(10, -10, z);
|
|
glEnd();
|
|
|
|
glBegin(GL_POLYGON);
|
|
glColor3f(1,0,0);
|
|
glVertex3f(-2, -2, z);
|
|
glVertex3f(-2, 2, z);
|
|
glVertex3f(2, 2, z);
|
|
glVertex3f(2, -2, z);
|
|
glEnd();
|
|
|
|
|
|
glBegin(GL_POLYGON);
|
|
glColor3f(.5,.5,1);
|
|
glVertex3f(-1, -1, z);
|
|
glVertex3f(-1, 1, z);
|
|
glVertex3f(1, 1, z);
|
|
glVertex3f(1, -1, z);
|
|
glEnd();
|
|
|
|
/***********************************************************************
|
|
*/
|
|
glViewport(0, 0, win_width, win_height);
|
|
glBegin(GL_LINES);
|
|
glColor3f(1,1,0);
|
|
glVertex3f(-1, 0, z);
|
|
glVertex3f(1, 0, z);
|
|
|
|
glVertex3f(0, -1, z);
|
|
glVertex3f(0, 1, z);
|
|
glEnd();
|
|
|
|
|
|
/***********************************************************************
|
|
*/
|
|
glViewport(tx, ty, w, h);
|
|
glBegin(GL_TRIANGLES);
|
|
glColor3f(1,0,0);
|
|
glVertex3f(-1, -1, z);
|
|
glVertex3f(0, -1, z);
|
|
glVertex3f(-.5, -.5, z);
|
|
|
|
glColor3f(1,1,1);
|
|
glVertex3f(0, -1, z);
|
|
glVertex3f(1, -1, z);
|
|
glVertex3f(.5, -.5, z);
|
|
|
|
glVertex3f(-.5, -.5, z);
|
|
glVertex3f(.5, -.5, z);
|
|
glVertex3f(0, 0, z);
|
|
|
|
|
|
glColor3f(0,1,0);
|
|
glVertex3f(1, 1, z);
|
|
glVertex3f(0, 1, z);
|
|
glVertex3f(.5, .5, z);
|
|
|
|
glColor3f(1,1,1);
|
|
glVertex3f(0, 1, z);
|
|
glVertex3f(-1, 1, z);
|
|
glVertex3f(-.5, .5, z);
|
|
|
|
glVertex3f(.5, .5, z);
|
|
glVertex3f(-.5, .5, z);
|
|
glVertex3f( 0, 0, z);
|
|
|
|
glEnd();
|
|
|
|
|
|
glViewport(0, 0, win_width, win_height);
|
|
|
|
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, z);
|
|
glVertex3f(1, f, z);
|
|
|
|
glVertex3f(f, -1, z);
|
|
glVertex3f(f, 1, z);
|
|
}
|
|
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:
|
|
break;
|
|
}
|
|
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;
|
|
}
|