-/* $Id: stex3d.c,v 1.6 2002/04/22 16:03:37 brianp Exp $ */
+/* $Id: stex3d.c,v 1.7 2002/10/23 14:00:01 brianp Exp $ */
/*-----------------------------
* stex3d.c GL example of the mesa 3d-texture extention to simulate procedural
* dbarrero@pegasus.uniandes.edu.co
*
* Converted to GLUT by brianp on 1/1/98
+ * Massive clean-up on 2002/10/23 by brianp
*
*
* cc stex3d.c -o stex3d -lglut -lMesaGLU -lMesaGL -lX11 -lXext -lm
#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;
+#define NOISE_TEXTURE 1
+#define GRADIENT_TEXTURE 2
+
+#define TORUS 1
+#define SPHERE 2
+
+static int tex_width=64, tex_height=64, tex_depth=64;
+static float angx=0, angy=0, angz=0;
+static GLuint DList;
+static int texgen = 2, animate = 1, smooth = 1;
+static int CurTexture = NOISE_TEXTURE, CurObject = TORUS;
+
+
+static void
+BuildTorus(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 = 0.25;
+ float outerRadius = 0.5;
+ float scalFac;
+
+ rings = 16;
+ sides = 12;
+ scalFac = 1 / (outerRadius * 2);
+
+ glNewList(TORUS, 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 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);
+
+/*--------------------------------------------------------------------
+ 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 128
+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.;
+
+static 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 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();
+static void
+initNoise(void)
+{
+ /*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];
+ }
}
-void create3Dtexture()
+
+static float
+turbulence(float point[3], float lofreq, float hifreq)
{
- 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");
+ 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 */
}
-void printHelp()
+
+static void
+create3Dtexture(void)
{
- 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");
+ unsigned char *voxels = NULL;
+ 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");
+
+ glBindTexture(GL_TEXTURE_3D, NOISE_TEXTURE);
+ 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);
+
+ glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+ glTexImage3D(GL_TEXTURE_3D, 0, GL_RGBA,
+ tex_width, tex_height, tex_depth,
+ 0, GL_RGBA, GL_UNSIGNED_BYTE, voxels);
+
+ free(voxels);
+
+ printf("finished setting up 3d texture image.\n");
}
-void setDefaults()
+
+static void
+printHelp(void)
{
- /* 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;
+ printf("\nUsage: stex3d <cmd line options>\n");
+ printf(" cmd line options:\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(" up/down rotate around X\n");
+ printf(" left/right rotate around Y\n");
+ printf(" z/Z rotate around Z\n");
+ printf(" a toggle animation\n");
+ printf(" s toggle smooth shading\n");
+ printf(" t toggle texgen mode\n");
+ printf(" o toggle object: torus/sphere\n");
+ printf(" i toggle texture image: noise/gradient\n");
}
-GLenum parseCmdLine(int argc, char **argv)
+
+static 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;
+ GLint i;
+
+ for (i = 1; i < argc; i++) {
+ if (strstr(argv[i], "-w") == 0) {
+ tex_width = atoi((argv[i]) + 2);
}
- }
- 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;
+ 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;
+}
+
+
+static void
+drawScene(void)
+{
+ static const GLfloat sPlane[4] = { 0.5, 0, 0, -.5 };
+ static const GLfloat tPlane[4] = { 0, 0.5, 0, -.5 };
+ static const GLfloat rPlane[4] = { 0, 0, 0.5, -.5 };
+
+ glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+ glPushMatrix();
+ if (texgen == 2) {
+ glTexGenfv(GL_S, GL_EYE_PLANE, sPlane);
+ glTexGenfv(GL_T, GL_EYE_PLANE, tPlane);
+ glTexGenfv(GL_R, GL_EYE_PLANE, rPlane);
+ }
+
+ glRotatef(angx, 1.0, 0.0, 0.0);
+ glRotatef(angy, 0.0, 1.0, 0.0);
+ glRotatef(angz, 0.0, 0.0, 1.0);
+
+ if (texgen == 1) {
+ glTexGenfv(GL_S, GL_EYE_PLANE, sPlane);
+ glTexGenfv(GL_T, GL_EYE_PLANE, tPlane);
+ glTexGenfv(GL_R, GL_EYE_PLANE, rPlane);
+ }
+
+ if (texgen) {
+ glEnable(GL_TEXTURE_GEN_S);
+ glEnable(GL_TEXTURE_GEN_T);
+ glEnable(GL_TEXTURE_GEN_R);
+ }
+ else {
+ glDisable(GL_TEXTURE_GEN_S);
+ glDisable(GL_TEXTURE_GEN_T);
+ glDisable(GL_TEXTURE_GEN_R);
+ }
+
+ glCallList(CurObject);
+ glPopMatrix();
+
+ glutSwapBuffers();
}
-void drawScene()
+
+static void
+resize(int w, int h)
{
- /* 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();
- ;
+ float ar = (float) w / (float) h;
+ float ax = 0.6 * ar;
+ float ay = 0.6;
+ glViewport(0, 0, (GLint) w, (GLint) h);
+ glMatrixMode(GL_PROJECTION);
+ glLoadIdentity();
+ glFrustum(-ax, ax, -ay, ay, 2, 20);
+ /*glOrtho(-2, 2, -2, 2, -10, 10);*/
+ glMatrixMode(GL_MODELVIEW);
+ glLoadIdentity();
+ glTranslatef(0, 0, -4);
}
-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
+Idle(void)
+{
+ float t = glutGet(GLUT_ELAPSED_TIME);
+ angx = 0.01 * t;
+ angy = 0.03 * t;
+ angz += 0;
+ glutPostRedisplay();
}
-static void cleanEverything(void)
+
+static void
+SpecialKey(int k, int x, int y)
{
-/* free(voxels); */
+ switch (k) {
+ case GLUT_KEY_UP:
+ angx += 5.0;
+ break;
+ case GLUT_KEY_DOWN:
+ angx -= 5.0;
+ break;
+ case GLUT_KEY_LEFT:
+ angy += 5.0;
+ break;
+ case GLUT_KEY_RIGHT:
+ angy -= 5.0;
+ break;
+ default:
+ return;
+ }
+ glutPostRedisplay();
}
-void KeyHandler( unsigned char key, int x, int y )
+static void
+KeyHandler(unsigned char key, int x, int y)
{
+ static const char *mode[] = {
+ "glTexCoord3f (no texgen)",
+ "texgen fixed to eye coords",
+ "texgen fixed to object coords"
+ };
(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':
+ switch (key) {
+ case 27:
+ case 'q':
+ case 'Q': /* quit game. */
+ exit(0);
+ break;
+ case 'z':
+ angz += 10;
+ break;
+ case 'Z':
+ angz -= 10;
+ break;
+ case 's':
+ smooth = !smooth;
+ if (smooth)
glShadeModel(GL_SMOOTH);
- break;
- case 'S':
+ else
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;
+ break;
+ case 't':
+ texgen++;
+ if (texgen > 2)
+ texgen = 0;
+ printf("Texgen: %s\n", mode[texgen]);
+ break;
+ case 'o':
+ if (CurObject == TORUS)
+ CurObject = SPHERE;
+ else
+ CurObject = TORUS;
+ break;
+ case 'i':
+ if (CurTexture == NOISE_TEXTURE)
+ CurTexture = GRADIENT_TEXTURE;
+ else
+ CurTexture = NOISE_TEXTURE;
+ glBindTexture(GL_TEXTURE_3D, CurTexture);
+ break;
+ case 'a':
+ animate = !animate;
+ if (animate)
+ glutIdleFunc(Idle);
+ else
+ glutIdleFunc(NULL);
+ 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
-----------------------------------------------------------------------*/
+void
+create3Dgradient(void)
+{
+ unsigned char *v;
+ int i, j, k;
+ unsigned char *voxels = NULL;
+
+ voxels = (unsigned char *) malloc(4 * tex_width * tex_height * tex_depth);
+ v = voxels;
+
+ for (i = 0; i < tex_depth; i++) {
+ for (j = 0; j < tex_height; j++) {
+ for (k = 0; k < tex_width; k++) {
+ GLint r = (255 * i) / (tex_depth - 1);
+ GLint g = (255 * j) / (tex_height - 1);
+ GLint b = (255 * k) / (tex_width - 1);
+ *v++ = r;
+ *v++ = g;
+ *v++ = b;
+ *v++ = 255;
+ }
+ }
+ }
-#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;
+ glBindTexture(GL_TEXTURE_3D, GRADIENT_TEXTURE);
+ 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);
- setup(0, bx0,bx1, rx0,rx1);
- setup(1, by0,by1, ry0,ry1);
- setup(2, bz0,bz1, rz0,rz1);
+ glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+ glTexImage3D(GL_TEXTURE_3D, 0, GL_RGBA,
+ tex_width, tex_height, tex_depth,
+ 0, GL_RGBA, GL_UNSIGNED_BYTE, voxels);
- i = p[ bx0 ];
- j = p[ bx1 ];
+ free(voxels);
+}
- 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);
+static void
+init(void)
+{
+ static const GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };
+ static const GLfloat mat_shininess[] = { 25.0 };
+ static const GLfloat gray[] = { 0.6, 0.6, 0.6, 0.0 };
+ static const GLfloat white[] = { 1.0, 1.0, 1.0, 0.0 };
+ static const GLfloat light_position[] = { 0.0, 1.0, 1.0, 0.0 };
+
+ int max;
+
+ /* 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);
+ }
+ }
+ printf("GL_RENDERER: %s\n", (char *) glGetString(GL_RENDERER));
+ glGetIntegerv(GL_MAX_3D_TEXTURE_SIZE, &max);
+ printf("GL_MAX_3D_TEXTURE_SIZE: %d\n", max);
+ printf("Current 3D texture size: %d x %d x %d\n",
+ tex_width, tex_height, tex_depth);
- q = g[ b00 + bz0 ] ; u = at(rx0,ry0,rz0);
- q = g[ b10 + bz0 ] ; v = at(rx1,ry0,rz0);
- a = lerp(sx, u, v);
+ /* init light */
+ 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);
- q = g[ b01 + bz0 ] ; u = at(rx0,ry1,rz0);
- q = g[ b11 + bz0 ] ; v = at(rx1,ry1,rz0);
- b = lerp(sx, u, v);
+ glClearColor(.5, .5, .5, 0);
- c = lerp(sy, a, b); /* interpolate in y at lo x */
+ /* create torus for texturing */
+ DList = glGenLists(1);
- q = g[ b00 + bz1 ] ; u = at(rx0,ry0,rz1);
- q = g[ b10 + bz1 ] ; v = at(rx1,ry0,rz1);
- a = lerp(sx, u, v);
+ glNewList(SPHERE, GL_COMPILE);
+ glutSolidSphere(0.95, 30, 15);
+ glEndList();
- q = g[ b01 + bz1 ] ; u = at(rx0,ry1,rz1);
- q = g[ b11 + bz1 ] ; v = at(rx1,ry1,rz1);
- b = lerp(sx, u, v);
+ BuildTorus();
- d = lerp(sy, a, b); /* interpolate in y at hi x */
- return 1.5 * lerp(sz, c, d); /* interpolate in z */
-}
+ create3Dgradient();
-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];
- }
+ initNoise();
+ create3Dtexture();
+
+ glEnable(GL_TEXTURE_3D);
+
+ /*
+ glBlendFunc(GL_SRC_COLOR, GL_SRC_ALPHA);
+ glEnable(GL_BLEND);
+ */
+ glEnable(GL_DEPTH_TEST);
+
+ glColor3f(0.6, 0.7, 0.8);
}
-float turbulence(float point[3], float lofreq, float hifreq)
+
+int
+main(int argc, char **argv)
{
- 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 */
+ glutInit(&argc, argv);
+
+ if (parseCmdLine(argc, argv) == GL_FALSE) {
+ exit(0);
+ }
+
+ glutInitWindowPosition(0, 0);
+ glutInitWindowSize(400, 400);
+ glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);
+
+ if (glutCreateWindow("stex3d") <= 0) {
+ exit(0);
+ }
+
+ init();
+
+ printHelp();
+
+ glutReshapeFunc(resize);
+ glutKeyboardFunc(KeyHandler);
+ glutSpecialFunc(SpecialKey);
+ glutDisplayFunc(drawScene);
+ if (animate)
+ glutIdleFunc(Idle);
+ glutMainLoop();
+ return 0;
}