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/* $Id: stex3d.c,v 1.5 2000/06/27 17:04:43 brianp Exp $ */
/*-----------------------------
* stex3d.c GL example of the mesa 3d-texture extention to simulate procedural
* texturing, it uses a perlin noise and turbulence functions.
*
* Author: Daniel Barrero
* barrero@irit.fr
* dbarrero@pegasus.uniandes.edu.co
*
* Converted to GLUT by brianp on 1/1/98
*
*
* cc stex3d.c -o stex3d -lglut -lMesaGLU -lMesaGL -lX11 -lXext -lm
*
*---------------------------- */
/*
* $Log: stex3d.c,v $
* Revision 1.5 2000/06/27 17:04:43 brianp
* fixed compiler warnings
*
* Revision 1.4 2000/03/22 19:48:57 brianp
* converted from GL_EXT_texture3D to GL 1.2
*
* Revision 1.3 1999/12/16 08:54:22 brianp
* added a cast to malloc call
*
* Revision 1.2 1999/09/17 12:27:01 brianp
* silenced some warnings
*
* Revision 1.1.1.1 1999/08/19 00:55:40 jtg
* Imported sources
*
* Revision 3.1 1998/06/09 01:53:49 brianp
* main() should return an int
*
* Revision 3.0 1998/02/14 18:42:29 brianp
* initial rev
*
*/
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <GL/gl.h>
#include <GL/glut.h>
/* function declarations */
#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif
void init(void),
printHelp(void),
create3Dtexture(void),
setDefaults(void),
drawScene(void),
resize(int w, int h),
buildFigure(void),
initNoise(void);
float turbulence(float point[3], float lofreq, float hifreq);
void KeyHandler( unsigned char key, int x, int y );
GLenum parseCmdLine(int argc, char **argv);
float noise3(float vec[3]);
/* global variables */
GLenum rgb, doubleBuffer, directRender, windType; /* visualization state*/
float tex_width,tex_height,tex_depth; /* texture volume dimensions */
unsigned char *voxels; /* texture data ptr */
int angx,angy,angz;
GLuint figure;
/*function definitions */
int main(int argc, char **argv)
{
if (parseCmdLine(argc, argv) == GL_FALSE) {
exit(0);
}
glutInitWindowPosition(0, 0);
glutInitWindowSize(400, 400);
windType = (rgb) ? GLUT_RGB : GLUT_INDEX;
windType |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
windType |= GLUT_DEPTH;
glutInitDisplayMode(windType);
if (glutCreateWindow("stex3d") <= 0) {
exit(0);
}
/* init all */
init();
glutReshapeFunc(resize);
glutKeyboardFunc(KeyHandler);
glutDisplayFunc(drawScene);
glutMainLoop();
return 0;
}
void init()
{
/* init light */
GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };
GLfloat mat_shininess[] = { 25.0 };
GLfloat gray[] = { 0.6, 0.6, 0.6, 0.0 };
GLfloat white[] = { 1.0, 1.0, 1.0, 0.0 };
GLfloat light_position[] = { 0.0, 1.0, 1.0, 0.0 };
glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess);
glLightfv(GL_LIGHT1, GL_POSITION, light_position);
glLightfv(GL_LIGHT1, GL_AMBIENT, gray);
glLightfv(GL_LIGHT1, GL_DIFFUSE, white);
glLightfv(GL_LIGHT1, GL_SPECULAR, white);
glColorMaterial(GL_FRONT, GL_DIFFUSE);
glEnable(GL_COLOR_MATERIAL);
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT1);
/* create torus for texturing */
figure=glGenLists(1);
buildFigure();
/* tkSolidTorus(figure,0.3,1.2);*/
/* start the noise function variables */
initNoise();
/* see if we have OpenGL 1.2 or later, for 3D texturing */
{
const char *version = (const char *) glGetString(GL_VERSION);
if (strncmp(version, "1.0", 3) == 0 ||
strncmp(version, "1.1", 3) == 0) {
printf("Sorry, OpenGL 1.2 or later is required\n");
exit(1);
}
}
/* if texture is supported then generate the texture */
create3Dtexture();
glEnable(GL_TEXTURE_3D);
/*
glBlendFunc(GL_SRC_COLOR, GL_SRC_ALPHA);
glEnable(GL_BLEND);
*/
glEnable(GL_DEPTH_TEST);
glShadeModel(GL_FLAT);
glColor3f(0.6,0.7,0.8);
}
void buildFigure(void)
{ GLint i, j;
float theta1, phi1, theta2, phi2, rings, sides;
float v0[03], v1[3], v2[3], v3[3];
float t0[03], t1[3], t2[3], t3[3];
float n0[3], n1[3], n2[3], n3[3];
float innerRadius=0.4;
float outerRadius=0.8;
float scalFac;
rings = 8;
sides = 10;
scalFac=1/(outerRadius*2);
glNewList(figure, GL_COMPILE);
for (i = 0; i < rings; i++) {
theta1 = (float)i * 2.0 * M_PI / rings;
theta2 = (float)(i + 1) * 2.0 * M_PI / rings;
for (j = 0; j < sides; j++) {
phi1 = (float)j * 2.0 * M_PI / sides;
phi2 = (float)(j + 1) * 2.0 * M_PI / sides;
v0[0] = cos(theta1) * (outerRadius + innerRadius * cos(phi1));
v0[1] = -sin(theta1) * (outerRadius + innerRadius * cos(phi1));
v0[2] = innerRadius * sin(phi1);
v1[0] = cos(theta2) * (outerRadius + innerRadius * cos(phi1));
v1[1] = -sin(theta2) * (outerRadius + innerRadius * cos(phi1));
v1[2] = innerRadius * sin(phi1);
v2[0] = cos(theta2) * (outerRadius + innerRadius * cos(phi2));
v2[1] = -sin(theta2) * (outerRadius + innerRadius * cos(phi2));
v2[2] = innerRadius * sin(phi2);
v3[0] = cos(theta1) * (outerRadius + innerRadius * cos(phi2));
v3[1] = -sin(theta1) * (outerRadius + innerRadius * cos(phi2));
v3[2] = innerRadius * sin(phi2);
n0[0] = cos(theta1) * (cos(phi1));
n0[1] = -sin(theta1) * (cos(phi1));
n0[2] = sin(phi1);
n1[0] = cos(theta2) * (cos(phi1));
n1[1] = -sin(theta2) * (cos(phi1));
n1[2] = sin(phi1);
n2[0] = cos(theta2) * (cos(phi2));
n2[1] = -sin(theta2) * (cos(phi2));
n2[2] = sin(phi2);
n3[0] = cos(theta1) * (cos(phi2));
n3[1] = -sin(theta1) * (cos(phi2));
n3[2] = sin(phi2);
t0[0] = v0[0]*scalFac + 0.5;
t0[1] = v0[1]*scalFac + 0.5;
t0[2] = v0[2]*scalFac + 0.5;
t1[0] = v1[0]*scalFac + 0.5;
t1[1] = v1[1]*scalFac + 0.5;
t1[2] = v1[2]*scalFac + 0.5;
t2[0] = v2[0]*scalFac + 0.5;
t2[1] = v2[1]*scalFac + 0.5;
t2[2] = v2[2]*scalFac + 0.5;
t3[0] = v3[0]*scalFac + 0.5;
t3[1] = v3[1]*scalFac + 0.5;
t3[2] = v3[2]*scalFac + 0.5;
glBegin(GL_POLYGON);
glNormal3fv(n3); glTexCoord3fv(t3); glVertex3fv(v3);
glNormal3fv(n2); glTexCoord3fv(t2); glVertex3fv(v2);
glNormal3fv(n1); glTexCoord3fv(t1); glVertex3fv(v1);
glNormal3fv(n0); glTexCoord3fv(t0); glVertex3fv(v0);
glEnd();
}
}
glEndList();
}
void create3Dtexture()
{
int i,j,k;
unsigned char *vp;
float vec[3];
int tmp;
printf("creating 3d textures...\n");
voxels = (unsigned char *) malloc((size_t)(4*tex_width*tex_height*tex_depth));
vp=voxels;
for (i=0;i<tex_width;i++){
vec[0]=i;
for (j=0;j<tex_height;j++) {
vec[1]=j;
for (k=0;k<tex_depth;k++) {
vec[2]=k;
tmp=(sin(k*i*j+turbulence(vec,0.01,1))+1)*127.5;
*vp++=0;
*vp++=0;
*vp++=tmp;
*vp++=tmp+128;
}
}
}
printf("setting up 3d texture...\n");
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_R, GL_REPEAT);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);
glTexImage3D(GL_TEXTURE_3D, 0, GL_RGBA,
tex_width, tex_height, tex_depth,
0, GL_RGBA, GL_UNSIGNED_BYTE, voxels);
printf("finished setting up 3d texture image...\n");
}
void printHelp()
{
printf("\nUsage: stex3d <cmd line options>\n");
printf(" cmd line options:\n");
printf(" -help print this help!\n");
printf(" -rgb RGBA mode. (Default)\n");
printf(" -ci Color index mode.\n");
printf(" -sb Single buffer mode. (Default)\n");
printf(" -db Double buffer mode. \n");
printf(" -dr Direct render mode.\n");
printf(" -ir Indirect render mode. (Default)\n");
printf(" -wxxx Width of the texture (Default=64)\n");
printf(" -hxxx Height of the texture (Default=64)\n");
printf(" -dxxx Depth of the texture (Default=64)\n");
printf(" Keyboard Options:\n");
printf(" 1 Object Texture coordinates (Default)\n");
printf(" 2 Eye Texture coordinates \n");
printf(" x rotate around x clockwise\n");
printf(" X rotate around x counter clockwise\n");
printf(" y rotate around y clockwise\n");
printf(" Y rotate around y counter clockwise\n");
printf(" z rotate around z clockwise\n");
printf(" Z rotate around z counter clockwise\n");
printf(" t enable 3-D texuring (Default)\n");
printf(" T disable 3-D texuring\n");
printf(" s smooth shading \n");
printf(" S flat shading (Default)\n");
}
void setDefaults()
{
/* visualization defaults */
rgb = GL_TRUE;
doubleBuffer = GL_FALSE;
directRender = GL_TRUE;
angx=130;
angy=30;
angz=0;
/* texture values */
tex_width=64;
tex_height=64;
tex_depth=64;
}
GLenum parseCmdLine(int argc, char **argv)
{
GLint i;
setDefaults();
for (i = 1; i < argc; i++) {
if (strcmp(argv[i], "-ci") == 0) {
rgb = GL_FALSE;
} else if (strcmp(argv[i], "-rgb") == 0) {
rgb = GL_TRUE;
} else if (strcmp(argv[i], "-sb") == 0) {
doubleBuffer = GL_FALSE;
} else if (strcmp(argv[i], "-db") == 0) {
doubleBuffer = GL_TRUE;
} else if (strcmp(argv[i], "-dr") == 0) {
directRender = GL_TRUE;
} else if (strcmp(argv[i], "-ir") == 0) {
directRender = GL_FALSE;
} else if (strstr(argv[i], "-w") == 0) {
tex_width=atoi((argv[i])+2);
} else if (strstr(argv[i], "-h") == 0) {
tex_height=atoi((argv[i])+2);
} else if (strstr(argv[i], "-d") == 0) {
tex_depth=atoi((argv[i])+2);
} else if (strcmp(argv[i], "-help") == 0) {
printHelp();
return GL_FALSE;
} else {
printf("%s (Bad option).\n", argv[i]);
printHelp();
return GL_FALSE;
}
}
if(tex_width==0 || tex_height==0 || tex_depth==0) {
printf("%s (Bad option).\n", "size parameters can't be 0");
printHelp();
return GL_FALSE;
}
return GL_TRUE;
}
void drawScene()
{
/* clear background, z buffer etc */
glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
glPushMatrix();
glRotatef(angx,1.0,0.0,0.0);
glRotatef(angy,0.0,1.0,0.0);
glRotatef(angz,0.0,0.0,1.0);
glCallList(figure);
glPopMatrix();
glFlush();
if(doubleBuffer)
glutSwapBuffers();
;
}
void resize(int w, int h)
{
glViewport(0, 0, (GLint)w, (GLint)h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(-2,2,-2,2,-5,10);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glTranslatef(0,0,-5);
}
static void cleanEverything(void)
{
/* free(voxels); */
}
void KeyHandler( unsigned char key, int x, int y )
{
(void) x;
(void) y;
switch(key) {
case 27:
case 'q':
case 'Q': /* quit game. */
cleanEverything();
exit(0);
break;
case 'x':
angx+=10;
break;
case 'X':
angx-=10;
break;
case 'y':
angy+=10;
break;
case 'Y':
angy-=10;
break;
case 'z':
angz+=10;
break;
case 'Z':
angz-=10;
break;
case 't':
glEnable(GL_TEXTURE_3D);
break;
case 'T':
glDisable(GL_TEXTURE_3D);
break;
case 's':
glShadeModel(GL_SMOOTH);
break;
case 'S':
glShadeModel(GL_FLAT);
break;
case '1':
glDisable(GL_TEXTURE_GEN_S);
glDisable(GL_TEXTURE_GEN_T);
glDisable(GL_TEXTURE_GEN_R);
break;
case '2':
glEnable(GL_TEXTURE_GEN_S);
glEnable(GL_TEXTURE_GEN_T);
glEnable(GL_TEXTURE_GEN_R);
break;
default:
break;
}
glutPostRedisplay();
}
/*--------------------------------------------------------------------
noise function over R3 - implemented by a pseudorandom tricubic spline
EXCERPTED FROM SIGGRAPH 92, COURSE 23
PROCEDURAL MODELING
Ken Perlin
New York University
----------------------------------------------------------------------*/
#define DOT(a,b) (a[0] * b[0] + a[1] * b[1] + a[2] * b[2])
#define B 256
static int p[B + B + 2];
static float g[B + B + 2][3];
#define setup(i,b0,b1,r0,r1) \
t = vec[i] + 10000.; \
b0 = ((int)t) & (B-1); \
b1 = (b0+1) & (B-1); \
r0 = t - (int)t; \
r1 = r0 - 1.;
float noise3(float vec[3])
{
int bx0, bx1, by0, by1, bz0, bz1, b00, b10, b01, b11;
float rx0, rx1, ry0, ry1, rz0, rz1, *q, sx, sy, sz, a, b, c, d, t, u, v;
register int i, j;
setup(0, bx0,bx1, rx0,rx1);
setup(1, by0,by1, ry0,ry1);
setup(2, bz0,bz1, rz0,rz1);
i = p[ bx0 ];
j = p[ bx1 ];
b00 = p[ i + by0 ];
b10 = p[ j + by0 ];
b01 = p[ i + by1 ];
b11 = p[ j + by1 ];
#define at(rx,ry,rz) ( rx * q[0] + ry * q[1] + rz * q[2] )
#define surve(t) ( t * t * (3. - 2. * t) )
#define lerp(t, a, b) ( a + t * (b - a) )
sx = surve(rx0);
sy = surve(ry0);
sz = surve(rz0);
q = g[ b00 + bz0 ] ; u = at(rx0,ry0,rz0);
q = g[ b10 + bz0 ] ; v = at(rx1,ry0,rz0);
a = lerp(sx, u, v);
q = g[ b01 + bz0 ] ; u = at(rx0,ry1,rz0);
q = g[ b11 + bz0 ] ; v = at(rx1,ry1,rz0);
b = lerp(sx, u, v);
c = lerp(sy, a, b); /* interpolate in y at lo x */
q = g[ b00 + bz1 ] ; u = at(rx0,ry0,rz1);
q = g[ b10 + bz1 ] ; v = at(rx1,ry0,rz1);
a = lerp(sx, u, v);
q = g[ b01 + bz1 ] ; u = at(rx0,ry1,rz1);
q = g[ b11 + bz1 ] ; v = at(rx1,ry1,rz1);
b = lerp(sx, u, v);
d = lerp(sy, a, b); /* interpolate in y at hi x */
return 1.5 * lerp(sz, c, d); /* interpolate in z */
}
void initNoise()
{
/*long random();*/
int i, j, k;
float v[3], s;
/* Create an array of random gradient vectors uniformly on the unit sphere */
/*srandom(1);*/
srand(1);
for (i = 0 ; i < B ; i++) {
do { /* Choose uniformly in a cube */ for (j=0 ; j<3 ; j++)
v[j] = (float)((rand() % (B + B)) - B) / B;
s = DOT(v,v);
} while (s > 1.0); /* If not in sphere try again */ s = sqrt(s);
for (j = 0 ; j < 3 ; j++) /* Else normalize */
g[i][j] = v[j] / s;
}
/* Create a pseudorandom permutation of [1..B] */
for (i = 0 ; i < B ; i++)
p[i] = i;
for (i = B ; i > 0 ; i -= 2) {
k = p[i];
p[i] = p[j = rand() % B];
p[j] = k;
}
/* Extend g and p arrays to allow for faster indexing */
for (i = 0 ; i < B + 2 ; i++) {
p[B + i] = p[i];
for (j = 0 ; j < 3 ; j++)
g[B + i][j] = g[i][j];
}
}
float turbulence(float point[3], float lofreq, float hifreq)
{
float freq, t, p[3];
p[0] = point[0] + 123.456;
p[1] = point[1];
p[2] = point[2];
t = 0;
for (freq = lofreq ; freq < hifreq ; freq *= 2.) {
t += fabs(noise3(p)) / freq;
p[0] *= 2.;
p[1] *= 2.;
p[2] *= 2.;
}
return t - 0.3; /* readjust to make mean value = 0.0 */
}
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