#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <string.h>
#if defined (WIN32)|| defined(_WIN32)
#include <windows.h>
#include <mmsystem.h>
#endif
#include <GL/glut.h>
#include "readtex.h"
#ifdef XMESA
#include "GL/xmesa.h"
static int fullscreen = 1;
#endif
static int WIDTH = 640;
static int HEIGHT = 480;
static GLint T0;
static GLint Frames;
#define MAX_LOD 9
#define TEX_SKY_WIDTH 256
#define TEX_SKY_HEIGHT TEX_SKY_WIDTH
#ifndef M_PI
#define M_PI 3.1415926535
#endif
#define FROM_NONE 0
#define FROM_DOWN 1
#define FROM_UP 2
#define FROM_LEFT 3
#define FROM_RIGHT 4
#define FROM_FRONT 5
#define FROM_BACK 6
static int win = 0;
static float obs[3] = { 3.8, 0.0, 0.0 };
static float dir[3];
static float v = 0.0;
static float alpha = -90.0;
static float beta = 90.0;
static int fog = 1;
static int bfcull = 1;
static int usetex = 1;
static int help = 1;
static int poutline = 0;
static int normext = 1;
static int joyavailable = 0;
static int joyactive = 0;
static int LODbias = 3;
static int maxdepth = MAX_LOD;
static unsigned int totpoly = 0;
static GLuint t1id, t2id;
static GLuint skydlist, LODdlist[MAX_LOD], LODnumpoly[MAX_LOD];
static void
initlight(void)
{
GLfloat lspec[4] = { 1.0, 1.0, 1.0, 1.0 };
static GLfloat lightpos[4] = { 30, 15.0, 30.0, 1.0 };
glLightfv(GL_LIGHT0, GL_POSITION, lightpos);
glLightfv(GL_LIGHT0, GL_SPECULAR, lspec);
glMaterialf(GL_FRONT_AND_BACK, GL_SHININESS, 32.0);
glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, lspec);
}
static void
initdlists(void)
{
static int slicetable[MAX_LOD][2] = {
{21, 10},
{18, 9},
{15, 8},
{12, 7},
{9, 6},
{7, 5},
{5, 4},
{4, 3},
{3, 2}
};
GLUquadricObj *obj;
int i, xslices, yslices;
obj = gluNewQuadric();
skydlist = glGenLists(1);
glNewList(skydlist, GL_COMPILE);
glBindTexture(GL_TEXTURE_2D, t2id);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
glColor3f(1.0f, 1.0f, 1.0f);
gluQuadricDrawStyle(obj, GLU_FILL);
gluQuadricNormals(obj, GLU_NONE);
gluQuadricTexture(obj, GL_TRUE);
gluQuadricOrientation(obj, GLU_INSIDE);
gluSphere(obj, 40.0f, 18, 9);
glEndList();
for (i = 0; i < MAX_LOD; i++) {
LODdlist[i] = glGenLists(1);
glNewList(LODdlist[i], GL_COMPILE);
gluQuadricDrawStyle(obj, GLU_FILL);
gluQuadricNormals(obj, GLU_SMOOTH);
gluQuadricTexture(obj, GL_TRUE);
gluQuadricOrientation(obj, GLU_OUTSIDE);
xslices = slicetable[i][0];
yslices = slicetable[i][1];
gluSphere(obj, 1.0f, xslices, yslices);
LODnumpoly[i] = xslices * (yslices - 2) + 2 * (xslices - 1);
glEndList();
}
}
static void
inittextures(void)
{
GLubyte tsky[TEX_SKY_HEIGHT][TEX_SKY_WIDTH][3];
GLuint x, y;
GLfloat fact;
GLenum gluerr;
glGenTextures(1, &t1id);
glBindTexture(GL_TEXTURE_2D, t1id);
if (!LoadRGBMipmaps("../images/bw.rgb", 3)) {
fprintf(stderr, "Error reading a texture.\n");
exit(-1);
}
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,
GL_LINEAR_MIPMAP_LINEAR);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glGenTextures(1, &t2id);
glBindTexture(GL_TEXTURE_2D, t2id);
for (y = 0; y < TEX_SKY_HEIGHT; y++)
for (x = 0; x < TEX_SKY_WIDTH; x++)
if (y < TEX_SKY_HEIGHT / 2) {
fact = y / (GLfloat) (TEX_SKY_HEIGHT / 2);
tsky[y][x][0] =
(GLubyte) (255.0f * (0.1f * fact + 0.3f * (1.0f - fact)));
tsky[y][x][1] =
(GLubyte) (255.0f * (0.2f * fact + 1.0f * (1.0f - fact)));
tsky[y][x][2] = 255;
}
else {
tsky[y][x][0] = tsky[TEX_SKY_HEIGHT - y - 1][x][0];
tsky[y][x][1] = tsky[TEX_SKY_HEIGHT - y - 1][x][1];
tsky[y][x][2] = 255;
}
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
if (
(gluerr =
gluBuild2DMipmaps(GL_TEXTURE_2D, 3, TEX_SKY_WIDTH, TEX_SKY_HEIGHT,
GL_RGB, GL_UNSIGNED_BYTE, (GLvoid *) (tsky)))) {
fprintf(stderr, "GLULib%s\n", (char *) gluErrorString(gluerr));
exit(-1);
}
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,
GL_LINEAR_MIPMAP_LINEAR);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
}
static void
calcposobs(void)
{
dir[0] = sin(alpha * M_PI / 180.0);
dir[1] = cos(alpha * M_PI / 180.0) * sin(beta * M_PI / 180.0);
dir[2] = cos(beta * M_PI / 180.0);
if (dir[0] < 1.0e-5 && dir[0] > -1.0e-5)
dir[0] = 0;
if (dir[1] < 1.0e-5 && dir[1] > -1.0e-5)
dir[1] = 0;
if (dir[2] < 1.0e-5 && dir[2] > -1.0e-5)
dir[2] = 0;
obs[0] += v * dir[0];
obs[1] += v * dir[1];
obs[2] += v * dir[2];
}
static void
special(int k, int x, int y)
{
switch (k) {
case GLUT_KEY_LEFT:
alpha -= 2.0;
break;
case GLUT_KEY_RIGHT:
alpha += 2.0;
break;
case GLUT_KEY_DOWN:
beta -= 2.0;
break;
case GLUT_KEY_UP:
beta += 2.0;
break;
}
}
static void
key(unsigned char k, int x, int y)
{
switch (k) {
case 27:
exit(0);
break;
case 'a':
v += 0.01;
break;
case 'z':
v -= 0.01;
break;
#ifdef XMESA
case ' ':
fullscreen = (!fullscreen);
XMesaSetFXmode(fullscreen ? XMESA_FX_FULLSCREEN : XMESA_FX_WINDOW);
break;
#endif
case '+':
LODbias--;
break;
case '-':
LODbias++;
break;
case 'j':
joyactive = (!joyactive);
break;
case 'h':
help = (!help);
break;
case 'f':
fog = (!fog);
break;
case 't':
usetex = (!usetex);
break;
case 'n':
normext = (!normext);
break;
case 'b':
if (bfcull) {
glDisable(GL_CULL_FACE);
bfcull = 0;
}
else {
glEnable(GL_CULL_FACE);
bfcull = 1;
}
break;
case 'p':
if (poutline) {
glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
poutline = 0;
usetex = 1;
}
else {
glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
poutline = 1;
usetex = 0;
}
break;
}
}
static void
reshape(int w, int h)
{
WIDTH = w;
HEIGHT = h;
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(90.0, w / (float) h, 0.8, 100.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glViewport(0, 0, w, h);
}
static void
printstring(void *font, char *string)
{
int len, i;
len = (int) strlen(string);
for (i = 0; i < len; i++)
glutBitmapCharacter(font, string[i]);
}
static void
printhelp(void)
{
glEnable(GL_BLEND);
glColor4f(0.5, 0.5, 0.5, 0.5);
glRecti(40, 40, 600, 440);
glDisable(GL_BLEND);
glColor3f(1.0, 0.0, 0.0);
glRasterPos2i(300, 420);
printstring(GLUT_BITMAP_TIMES_ROMAN_24, "Help");
glRasterPos2i(60, 390);
printstring(GLUT_BITMAP_TIMES_ROMAN_24, "h - Toggle Help");
glRasterPos2i(60, 360);
printstring(GLUT_BITMAP_TIMES_ROMAN_24, "t - Toggle Textures");
glRasterPos2i(60, 330);
printstring(GLUT_BITMAP_TIMES_ROMAN_24, "f - Toggle Fog");
glRasterPos2i(60, 300);
printstring(GLUT_BITMAP_TIMES_ROMAN_24, "b - Toggle Back face culling");
glRasterPos2i(60, 270);
printstring(GLUT_BITMAP_TIMES_ROMAN_24, "Arrow Keys - Rotate");
glRasterPos2i(60, 240);
printstring(GLUT_BITMAP_TIMES_ROMAN_24, "a - Increase velocity");
glRasterPos2i(60, 210);
printstring(GLUT_BITMAP_TIMES_ROMAN_24, "z - Decrease velocity");
glRasterPos2i(60, 180);
printstring(GLUT_BITMAP_TIMES_ROMAN_24, "p - Toggle Wire frame");
glRasterPos2i(60, 150);
printstring(GLUT_BITMAP_TIMES_ROMAN_24,
"n - Toggle GL_EXT_rescale_normal extension");
glRasterPos2i(60, 120);
printstring(GLUT_BITMAP_TIMES_ROMAN_24,
"+/- - Increase/decrease the Object maximum LOD");
glRasterPos2i(60, 90);
if (joyavailable)
printstring(GLUT_BITMAP_TIMES_ROMAN_24,
"j - Toggle jostick control (Joystick control available)");
else
printstring(GLUT_BITMAP_TIMES_ROMAN_24,
"(No Joystick control available)");
}
static void
dojoy(void)
{
#ifdef _WIN32
static UINT max[2] = { 0, 0 };
static UINT min[2] = { 0xffffffff, 0xffffffff }, center[2];
MMRESULT res;
JOYINFO joy;
res = joyGetPos(JOYSTICKID1, &joy);
if (res == JOYERR_NOERROR) {
joyavailable = 1;
if (max[0] < joy.wXpos)
max[0] = joy.wXpos;
if (min[0] > joy.wXpos)
min[0] = joy.wXpos;
center[0] = (max[0] + min[0]) / 2;
if (max[1] < joy.wYpos)
max[1] = joy.wYpos;
if (min[1] > joy.wYpos)
min[1] = joy.wYpos;
center[1] = (max[1] + min[1]) / 2;
if (joyactive) {
if (fabs(center[0] - (float) joy.wXpos) > 0.1 * (max[0] - min[0]))
alpha -=
2.0 * (center[0] - (float) joy.wXpos) / (max[0] - min[0]);
if (fabs(center[1] - (float) joy.wYpos) > 0.1 * (max[1] - min[1]))
beta += 2.0 * (center[1] - (float) joy.wYpos) / (max[1] - min[1]);
if (joy.wButtons & JOY_BUTTON1)
v += 0.01;
if (joy.wButtons & JOY_BUTTON2)
v -= 0.01;
}
}
else
joyavailable = 0;
#endif
}
static void
drawipers(int depth, int from)
{
int lod;
if (depth == maxdepth)
return;
lod = depth + LODbias;
if (lod < 0)
lod = 0;
if (lod >= MAX_LOD)
return;
switch (from) {
case FROM_NONE:
glCallList(LODdlist[lod]);
depth++;
drawipers(depth, FROM_DOWN);
drawipers(depth, FROM_UP);
drawipers(depth, FROM_FRONT);
drawipers(depth, FROM_BACK);
drawipers(depth, FROM_LEFT);
drawipers(depth, FROM_RIGHT);
break;
case FROM_FRONT:
glPushMatrix();
glTranslatef(0.0f, -1.5f, 0.0f);
glScalef(0.5f, 0.5f, 0.5f);
glCallList(LODdlist[lod]);
depth++;
drawipers(depth, FROM_DOWN);
drawipers(depth, FROM_UP);
drawipers(depth, FROM_FRONT);
drawipers(depth, FROM_LEFT);
drawipers(depth, FROM_RIGHT);
glPopMatrix();
break;
case FROM_BACK:
glPushMatrix();
glTranslatef(0.0f, 1.5f, 0.0f);
glScalef(0.5f, 0.5f, 0.5f);
glCallList(LODdlist[lod]);
depth++;
drawipers(depth, FROM_DOWN);
drawipers(depth, FROM_UP);
drawipers(depth, FROM_BACK);
drawipers(depth, FROM_LEFT);
drawipers(depth, FROM_RIGHT);
glPopMatrix();
break;
case FROM_LEFT:
glPushMatrix();
glTranslatef(-1.5f, 0.0f, 0.0f);
glScalef(0.5f, 0.5f, 0.5f);
glCallList(LODdlist[lod]);
depth++;
drawipers(depth, FROM_DOWN);
drawipers(depth, FROM_UP);
drawipers(depth, FROM_FRONT);
drawipers(depth, FROM_BACK);
drawipers(depth, FROM_LEFT);
glPopMatrix();
break;
case FROM_RIGHT:
glPushMatrix();
glTranslatef(1.5f, 0.0f, 0.0f);
glScalef(0.5f, 0.5f, 0.5f);
glCallList(LODdlist[lod]);
depth++;
drawipers(depth, FROM_DOWN);
drawipers(depth, FROM_UP);
drawipers(depth, FROM_FRONT);
drawipers(depth, FROM_BACK);
drawipers(depth, FROM_RIGHT);
glPopMatrix();
break;
case FROM_DOWN:
glPushMatrix();
glTranslatef(0.0f, 0.0f, 1.5f);
glScalef(0.5f, 0.5f, 0.5f);
glCallList(LODdlist[lod]);
depth++;
drawipers(depth, FROM_DOWN);
drawipers(depth, FROM_FRONT);
drawipers(depth, FROM_BACK);
drawipers(depth, FROM_LEFT);
drawipers(depth, FROM_RIGHT);
glPopMatrix();
break;
case FROM_UP:
glPushMatrix();
glTranslatef(0.0f, 0.0f, -1.5f);
glScalef(0.5f, 0.5f, 0.5f);
glCallList(LODdlist[lod]);
depth++;
drawipers(depth, FROM_UP);
drawipers(depth, FROM_FRONT);
drawipers(depth, FROM_BACK);
drawipers(depth, FROM_LEFT);
drawipers(depth, FROM_RIGHT);
glPopMatrix();
break;
}
totpoly += LODnumpoly[lod];
}
static void
draw(void)
{
static char frbuf[80] = "";
static GLfloat alpha = 0.0f;
static GLfloat beta = 0.0f;
static float fr = 0.0;
static double t0 = -1.;
double dt, t = glutGet(GLUT_ELAPSED_TIME) / 1000.0;
if (t0 < 0.0)
t0 = t;
dt = t - t0;
t0 = t;
dojoy();
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
if (usetex)
glEnable(GL_TEXTURE_2D);
else
glDisable(GL_TEXTURE_2D);
if (fog)
glEnable(GL_FOG);
else
glDisable(GL_FOG);
glPushMatrix();
calcposobs();
gluLookAt(obs[0], obs[1], obs[2],
obs[0] + dir[0], obs[1] + dir[1], obs[2] + dir[2],
0.0, 0.0, 1.0);
glEnable(GL_DEPTH_TEST);
glShadeModel(GL_SMOOTH);
glBindTexture(GL_TEXTURE_2D, t1id);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
glColor3f(1.0f, 1.0f, 1.0f);
glEnable(GL_LIGHT0);
glEnable(GL_LIGHTING);
if (normext)
glEnable(GL_RESCALE_NORMAL_EXT);
else
glEnable(GL_NORMALIZE);
glPushMatrix();
glRotatef(alpha, 0.0f, 0.0f, 1.0f);
glRotatef(beta, 1.0f, 0.0f, 0.0f);
totpoly = 0;
drawipers(0, FROM_NONE);
glPopMatrix();
alpha += 4.f * dt;
beta += 2.4f * dt;
glDisable(GL_LIGHTING);
glDisable(GL_LIGHT0);
glShadeModel(GL_FLAT);
if (normext)
glDisable(GL_RESCALE_NORMAL_EXT);
else
glDisable(GL_NORMALIZE);
glCallList(skydlist);
glPopMatrix();
sprintf(frbuf,
"Frame rate: %0.2f LOD: %d Tot. poly.: %d Poly/sec: %.1f",
fr, LODbias, totpoly, totpoly * fr);
glDisable(GL_TEXTURE_2D);
glDisable(GL_FOG);
glShadeModel(GL_FLAT);
glDisable(GL_DEPTH_TEST);
glMatrixMode(GL_PROJECTION);
glPushMatrix();
glLoadIdentity();
glOrtho(-0.5, 639.5, -0.5, 479.5, -1.0, 1.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glColor3f(1.0, 0.0, 0.0);
glRasterPos2i(10, 10);
printstring(GLUT_BITMAP_HELVETICA_18, frbuf);
glRasterPos2i(350, 470);
printstring(GLUT_BITMAP_HELVETICA_10,
"IperS V1.0 Written by David Bucciarelli (tech.hmw@plus.it)");
if (help)
printhelp();
glMatrixMode(GL_PROJECTION);
glPopMatrix();
glMatrixMode(GL_MODELVIEW);
glutSwapBuffers();
Frames++;
{
GLint t = glutGet(GLUT_ELAPSED_TIME);
if (t - T0 >= 2000) {
GLfloat seconds = (t - T0) / 1000.0;
fr = Frames / seconds;
T0 = t;
Frames = 0;
}
}
}
int
main(int ac, char **av)
{
float fogcolor[4] = { 0.7, 0.7, 0.7, 1.0 };
fprintf(stderr,
"IperS V1.0\nWritten by David Bucciarelli (tech.hmw@plus.it)\n");
glutInitWindowPosition(0, 0);
glutInitWindowSize(WIDTH, HEIGHT);
glutInit(&ac, av);
glutInitDisplayMode(GLUT_RGB | GLUT_DEPTH | GLUT_DOUBLE);
if (!(win = glutCreateWindow("IperS"))) {
fprintf(stderr, "Error, couldn't open window\n");
exit(-1);
}
reshape(WIDTH, HEIGHT);
glShadeModel(GL_SMOOTH);
glEnable(GL_DEPTH_TEST);
glEnable(GL_CULL_FACE);
glEnable(GL_TEXTURE_2D);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glEnable(GL_FOG);
glFogi(GL_FOG_MODE, GL_EXP2);
glFogfv(GL_FOG_COLOR, fogcolor);
glFogf(GL_FOG_DENSITY, 0.006);
glHint(GL_FOG_HINT, GL_NICEST);
inittextures();
initdlists();
initlight();
glClearColor(fogcolor[0], fogcolor[1], fogcolor[2], fogcolor[3]);
glClear(GL_COLOR_BUFFER_BIT);
calcposobs();
glutReshapeFunc(reshape);
glutDisplayFunc(draw);
glutKeyboardFunc(key);
glutSpecialFunc(special);
glutIdleFunc(draw);
glutMainLoop();
return 0;
}