Initial revision
diff --git a/progs/demos/isosurf.c b/progs/demos/isosurf.c
new file mode 100644
index 0000000..393197f
--- /dev/null
+++ b/progs/demos/isosurf.c
@@ -0,0 +1,821 @@
+/* $Id: isosurf.c,v 1.1 1999/08/19 00:55:40 jtg Exp $ */
+
+/*
+ * Display an isosurface of 3-D wind speed volume. Use arrow keys to
+ * rotate, S toggles smooth shading, L toggles lighting
+ * Brian Paul This file in public domain.
+ */
+
+/*
+ * $Log: isosurf.c,v $
+ * Revision 1.1 1999/08/19 00:55:40 jtg
+ * Initial revision
+ *
+ * Revision 3.4 1999/04/24 01:10:47 keithw
+ * clip planes, materials
+ *
+ * Revision 3.3 1999/03/31 19:42:14 keithw
+ * support for cva
+ *
+ * Revision 3.1 1998/11/01 20:30:20 brianp
+ * added benchmark feature (b key)
+ *
+ * Revision 3.0 1998/02/14 18:42:29 brianp
+ * initial rev
+ *
+ */
+
+
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <math.h>
+#include "GL/glut.h"
+
+#include "../util/readtex.c" /* I know, this is a hack. KW: me too. */
+#define TEXTURE_FILE "../images/reflect.rgb"
+
+#define LIT 0x1
+#define UNLIT 0x2
+#define TEXTURE 0x4
+#define NO_TEXTURE 0x8
+#define REFLECT 0x10
+#define NO_REFLECT 0x20
+#define POINT_FILTER 0x40
+#define LINEAR_FILTER 0x80
+#define IMMEDIATE 0x100
+#define DRAW_ARRAYS 0x200 /* or draw_elts, if compiled */
+#define ARRAY_ELT 0x400
+#define COMPILED 0x800
+#define NOT_COMPILED 0x1000
+#define SHADE_SMOOTH 0x2000
+#define SHADE_FLAT 0x4000
+#define TRIANGLES 0x8000
+#define STRIPS 0x10000
+#define USER_CLIP 0x20000
+#define NO_USER_CLIP 0x40000
+#define MATERIALS 0x80000
+#define NO_MATERIALS 0x100000
+#define QUIT 0x800000
+
+#define LIGHT_MASK (LIT|UNLIT)
+#define TEXTURE_MASK (TEXTURE|NO_TEXTURE)
+#define REFLECT_MASK (REFLECT|NO_REFLECT)
+#define FILTER_MASK (POINT_FILTER|LINEAR_FILTER)
+#define RENDER_STYLE_MASK (IMMEDIATE|DRAW_ARRAYS|ARRAY_ELT)
+#define COMPILED_MASK (COMPILED|NOT_COMPILED)
+#define MATERIAL_MASK (MATERIALS|NO_MATERIALS)
+#define PRIMITIVE_MASK (TRIANGLES|STRIPS)
+#define CLIP_MASK (USER_CLIP|NO_USER_CLIP)
+#define SHADE_MASK (SHADE_SMOOTH|SHADE_FLAT)
+
+#define MAXVERTS 10000
+static float data[MAXVERTS][6];
+static float compressed_data[MAXVERTS][6];
+static GLuint indices[MAXVERTS];
+static GLuint tri_indices[MAXVERTS*3];
+static GLfloat col[100][4];
+static GLint numverts, num_tri_verts, numuniq;
+
+static GLfloat xrot;
+static GLfloat yrot;
+static GLint state, allowed = ~0;
+static GLboolean doubleBuffer = GL_TRUE;
+static GLdouble plane[4] = {1.0, 0.0, -1.0, 0.0};
+
+
+static void read_surface( char *filename )
+{
+ FILE *f;
+
+ f = fopen(filename,"r");
+ if (!f) {
+ printf("couldn't read %s\n", filename);
+ exit(1);
+ }
+
+ numverts = 0;
+ while (!feof(f) && numverts<MAXVERTS) {
+ fscanf( f, "%f %f %f %f %f %f",
+ &data[numverts][0], &data[numverts][1], &data[numverts][2],
+ &data[numverts][3], &data[numverts][4], &data[numverts][5] );
+ numverts++;
+ }
+ numverts--;
+
+ printf("%d vertices, %d triangles\n", numverts, numverts-2);
+ fclose(f);
+}
+
+
+
+
+struct data_idx {
+ float *data;
+ int idx;
+ int uniq_idx;
+};
+
+
+#define COMPARE_FUNC( AXIS ) \
+int compare_axis_##AXIS( const void *a, const void *b ) \
+{ \
+ float t = ( (*(struct data_idx *)a).data[AXIS] - \
+ (*(struct data_idx *)b).data[AXIS] ); \
+ \
+ if (t < 0) return -1; \
+ if (t > 0) return 1; \
+ return 0; \
+}
+
+COMPARE_FUNC(0)
+COMPARE_FUNC(1)
+COMPARE_FUNC(2)
+COMPARE_FUNC(3)
+COMPARE_FUNC(4)
+COMPARE_FUNC(5)
+COMPARE_FUNC(6)
+
+int (*(compare[7]))( const void *a, const void *b ) =
+{
+ compare_axis_0,
+ compare_axis_1,
+ compare_axis_2,
+ compare_axis_3,
+ compare_axis_4,
+ compare_axis_5,
+ compare_axis_6,
+};
+
+
+#define VEC_ELT(f, s, i) (float *)(((char *)f) + s * i)
+
+static int sort_axis( int axis,
+ int vec_size,
+ int vec_stride,
+ struct data_idx *indices,
+ int start,
+ int finish,
+ float *out,
+ int uniq,
+ const float fudge )
+{
+ int i;
+
+ if (finish-start > 2)
+ {
+ qsort( indices+start, finish-start, sizeof(*indices), compare[axis] );
+ }
+ else if (indices[start].data[axis] > indices[start+1].data[axis])
+ {
+ struct data_idx tmp = indices[start];
+ indices[start] = indices[start+1];
+ indices[start+1] = tmp;
+ }
+
+ if (axis == vec_size-1) {
+ for (i = start ; i < finish ; ) {
+ float max = indices[i].data[axis] + fudge;
+ float *dest = VEC_ELT(out, vec_stride, uniq);
+ int j;
+
+ for (j = 0 ; j < vec_size ; j++)
+ dest[j] = indices[i].data[j];
+
+ for ( ; i < finish && max >= indices[i].data[axis]; i++)
+ indices[i].uniq_idx = uniq;
+
+ uniq++;
+ }
+ } else {
+ for (i = start ; i < finish ; ) {
+ int j = i + 1;
+ float max = indices[i].data[axis] + fudge;
+ while (j < finish && max >= indices[j].data[axis]) j++;
+ if (j == i+1) {
+ float *dest = VEC_ELT(out, vec_stride, uniq);
+ int k;
+
+ indices[i].uniq_idx = uniq;
+
+ for (k = 0 ; k < vec_size ; k++)
+ dest[k] = indices[i].data[k];
+
+ uniq++;
+ } else {
+ uniq = sort_axis( axis+1, vec_size, vec_stride,
+ indices, i, j, out, uniq, fudge );
+ }
+ i = j;
+ }
+ }
+
+ return uniq;
+}
+
+
+static void extract_indices1( const struct data_idx *in, unsigned int *out,
+ int n )
+{
+ int i;
+ for ( i = 0 ; i < n ; i++ ) {
+ out[in[i].idx] = in[i].uniq_idx;
+ }
+}
+
+
+static void compactify_arrays()
+{
+ int i;
+ struct data_idx *ind;
+
+ ind = (struct data_idx *) malloc( sizeof(struct data_idx) * numverts );
+
+ for (i = 0 ; i < numverts ; i++) {
+ ind[i].idx = i;
+ ind[i].data = data[i];
+ }
+
+ numuniq = sort_axis(0,
+ sizeof(compressed_data[0])/sizeof(float),
+ sizeof(compressed_data[0]),
+ ind,
+ 0,
+ numverts,
+ (float *)compressed_data,
+ 0,
+ 1e-6);
+
+ printf("Nr unique vertex/normal pairs: %d\n", numuniq);
+
+ extract_indices1( ind, indices, numverts );
+ free( ind );
+}
+
+static float myrand( float max )
+{
+ return max*rand()/(RAND_MAX+1.0);
+}
+
+
+static void make_tri_indices( void )
+{
+ unsigned int *v = tri_indices;
+ unsigned int parity = 0;
+ unsigned int i, j;
+
+ for (j=2;j<numverts;j++,parity^=1) {
+ if (parity) {
+ *v++ = indices[j-1];
+ *v++ = indices[j-2];
+ *v++ = indices[j];
+ } else {
+ *v++ = indices[j-2];
+ *v++ = indices[j-1];
+ *v++ = indices[j];
+ }
+ }
+
+ num_tri_verts = v - tri_indices;
+ printf("num_tri_verts: %d\n", num_tri_verts);
+
+ for (i = j = 0 ; i < num_tri_verts ; i += 600, j++) {
+ col[j][3] = 1;
+ col[j][2] = myrand(1);
+ col[j][1] = myrand(1);
+ col[j][0] = myrand(1);
+ }
+}
+
+#define MIN(x,y) (x < y) ? x : y
+
+static void draw_surface( void )
+{
+ GLuint i, j;
+
+ switch (state & (COMPILED_MASK|RENDER_STYLE_MASK|PRIMITIVE_MASK)) {
+#ifdef GL_EXT_vertex_array
+
+ case (COMPILED|DRAW_ARRAYS|STRIPS):
+ glDrawElements( GL_TRIANGLE_STRIP, numverts, GL_UNSIGNED_INT, indices );
+ break;
+
+
+ case (COMPILED|ARRAY_ELT|STRIPS):
+ glBegin( GL_TRIANGLE_STRIP );
+ for (i = 0 ; i < numverts ; i++)
+ glArrayElement( indices[i] );
+ glEnd();
+ break;
+
+ case (COMPILED|DRAW_ARRAYS|TRIANGLES):
+ case (NOT_COMPILED|DRAW_ARRAYS|TRIANGLES):
+ if (state & MATERIALS) {
+ for (j = i = 0 ; i < num_tri_verts ; i += 600, j++) {
+ GLuint nr = MIN(num_tri_verts-i, 600);
+ glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, col[j]);
+ glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, col[j]);
+ glDrawElements( GL_TRIANGLES, nr, GL_UNSIGNED_INT, tri_indices+i );
+ }
+ } else {
+ glDrawElements( GL_TRIANGLES, num_tri_verts, GL_UNSIGNED_INT,
+ tri_indices );
+ }
+
+ break;
+
+ /* Uses the original arrays (including duplicate elements):
+ */
+ case (NOT_COMPILED|DRAW_ARRAYS|STRIPS):
+ glDrawArraysEXT( GL_TRIANGLE_STRIP, 0, numverts );
+ break;
+
+ /* Uses the original arrays (including duplicate elements):
+ */
+ case (NOT_COMPILED|ARRAY_ELT|STRIPS):
+ glBegin( GL_TRIANGLE_STRIP );
+ for (i = 0 ; i < numverts ; i++)
+ glArrayElement( i );
+ glEnd();
+ break;
+
+ case (NOT_COMPILED|ARRAY_ELT|TRIANGLES):
+ case (COMPILED|ARRAY_ELT|TRIANGLES):
+ if (state & MATERIALS) {
+ for (j = i = 0 ; i < num_tri_verts ; i += 600, j++) {
+ GLuint nr = MIN(num_tri_verts-i, 600);
+ GLuint k;
+ glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, col[j]);
+ glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, col[j]);
+ glBegin( GL_TRIANGLES );
+ for (k = 0 ; k < nr ; k++)
+ glArrayElement( tri_indices[i+k] );
+ glEnd();
+ }
+ } else {
+ glBegin( GL_TRIANGLES );
+ for (i = 0 ; i < num_tri_verts ; i++)
+ glArrayElement( tri_indices[i] );
+ glEnd();
+ }
+ break;
+
+ case (NOT_COMPILED|IMMEDIATE|TRIANGLES):
+ if (state & MATERIALS) {
+ for (j = i = 0 ; i < num_tri_verts ; i += 600, j++) {
+ GLuint nr = MIN(num_tri_verts-i, 600);
+ GLuint k;
+ glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, col[j]);
+ glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, col[j]);
+ glBegin( GL_TRIANGLES );
+ for (k = 0 ; k < nr ; k++) {
+ glNormal3fv( &compressed_data[tri_indices[i+k]][3] );
+ glVertex3fv( &compressed_data[tri_indices[i+k]][0] );
+ }
+ glEnd();
+ }
+ } else {
+ glBegin( GL_TRIANGLES );
+ for (i = 0 ; i < num_tri_verts ; i++) {
+ glNormal3fv( &compressed_data[tri_indices[i]][3] );
+ glVertex3fv( &compressed_data[tri_indices[i]][0] );
+ }
+ glEnd();
+ }
+ break;
+
+#endif
+
+ /* Uses the original arrays (including duplicate elements):
+ */
+ default:
+ glBegin( GL_TRIANGLE_STRIP );
+ for (i=0;i<numverts;i++) {
+ glNormal3fv( &data[i][3] );
+ glVertex3fv( &data[i][0] );
+ }
+ glEnd();
+ }
+}
+
+
+
+static void Display(void)
+{
+ glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
+ draw_surface();
+ glFlush();
+ if (doubleBuffer) glutSwapBuffers();
+}
+
+/* KW: only do this when necessary, so CVA can re-use results.
+ */
+static void set_matrix( void )
+{
+ glMatrixMode(GL_MODELVIEW);
+ glLoadIdentity();
+ glTranslatef( 0.0, 0.0, -6.0 );
+ glRotatef( yrot, 0.0, 1.0, 0.0 );
+ glRotatef( xrot, 1.0, 0.0, 0.0 );
+}
+
+static void Benchmark( float xdiff, float ydiff )
+{
+ int startTime, endTime;
+ int draws;
+ double seconds, fps, triPerSecond;
+
+ printf("Benchmarking...\n");
+
+ draws = 0;
+ startTime = glutGet(GLUT_ELAPSED_TIME);
+ xrot = 0.0;
+ do {
+ xrot += xdiff;
+ yrot += ydiff;
+ set_matrix();
+ Display();
+ draws++;
+ endTime = glutGet(GLUT_ELAPSED_TIME);
+ } while (endTime - startTime < 5000); /* 5 seconds */
+
+ /* Results */
+ seconds = (double) (endTime - startTime) / 1000.0;
+ triPerSecond = (numverts - 2) * draws / seconds;
+ fps = draws / seconds;
+ printf("Result: triangles/sec: %g fps: %g\n", triPerSecond, fps);
+}
+
+
+static void InitMaterials(void)
+{
+ static float ambient[] = {0.1, 0.1, 0.1, 1.0};
+ static float diffuse[] = {0.5, 1.0, 1.0, 1.0};
+ static float position0[] = {0.0, 0.0, 20.0, 0.0};
+ static float position1[] = {0.0, 0.0, -20.0, 0.0};
+ static float front_mat_shininess[] = {60.0};
+ static float front_mat_specular[] = {0.2, 0.2, 0.2, 1.0};
+ static float front_mat_diffuse[] = {0.5, 0.28, 0.38, 1.0};
+ /*
+ static float back_mat_shininess[] = {60.0};
+ static float back_mat_specular[] = {0.5, 0.5, 0.2, 1.0};
+ static float back_mat_diffuse[] = {1.0, 1.0, 0.2, 1.0};
+ */
+ static float lmodel_ambient[] = {1.0, 1.0, 1.0, 1.0};
+ static float lmodel_twoside[] = {GL_FALSE};
+
+ glLightfv(GL_LIGHT0, GL_AMBIENT, ambient);
+ glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuse);
+ glLightfv(GL_LIGHT0, GL_POSITION, position0);
+ glEnable(GL_LIGHT0);
+
+ glLightfv(GL_LIGHT1, GL_AMBIENT, ambient);
+ glLightfv(GL_LIGHT1, GL_DIFFUSE, diffuse);
+ glLightfv(GL_LIGHT1, GL_POSITION, position1);
+ glEnable(GL_LIGHT1);
+
+ glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lmodel_ambient);
+ glLightModelfv(GL_LIGHT_MODEL_TWO_SIDE, lmodel_twoside);
+
+ glMaterialfv(GL_FRONT_AND_BACK, GL_SHININESS, front_mat_shininess);
+ glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, front_mat_specular);
+ glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, front_mat_diffuse);
+}
+
+
+
+#define UPDATE(o,n,mask) (o&=~mask, o|=n&mask)
+#define CHANGED(o,n,mask) ((n&mask) && \
+ (n&mask) != (o&mask) ? UPDATE(o,n,mask) : 0)
+
+static void ModeMenu(int m)
+{
+ m &= allowed;
+
+ if (!m) return;
+
+ if (m==QUIT)
+ exit(0);
+
+ if (CHANGED(state, m, FILTER_MASK)) {
+ if (m & LINEAR_FILTER) {
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+ } else {
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+ }
+ }
+
+ if (CHANGED(state, m, LIGHT_MASK)) {
+ if (m & LIT)
+ glEnable(GL_LIGHTING);
+ else
+ glDisable(GL_LIGHTING);
+ }
+
+ if (CHANGED(state, m, SHADE_MASK)) {
+ if (m & SHADE_SMOOTH)
+ glShadeModel(GL_SMOOTH);
+ else
+ glShadeModel(GL_FLAT);
+ }
+
+
+ if (CHANGED(state, m, TEXTURE_MASK)) {
+ if (m & TEXTURE)
+ glEnable(GL_TEXTURE_2D);
+ else
+ glDisable(GL_TEXTURE_2D);
+ }
+
+ if (CHANGED(state, m, REFLECT_MASK)) {
+ if (m & REFLECT) {
+ glEnable(GL_TEXTURE_GEN_S);
+ glEnable(GL_TEXTURE_GEN_T);
+ } else {
+ glDisable(GL_TEXTURE_GEN_S);
+ glDisable(GL_TEXTURE_GEN_T);
+ }
+ }
+
+ if (CHANGED(state, m, CLIP_MASK)) {
+ if (m & USER_CLIP) {
+ glEnable(GL_CLIP_PLANE0);
+ } else {
+ glDisable(GL_CLIP_PLANE0);
+ }
+ }
+
+#ifdef GL_EXT_vertex_array
+ if (CHANGED(state, m, (COMPILED_MASK|RENDER_STYLE_MASK|PRIMITIVE_MASK)))
+ {
+ if ((m & (COMPILED_MASK|PRIMITIVE_MASK)) == (NOT_COMPILED|STRIPS))
+ {
+ glVertexPointerEXT( 3, GL_FLOAT, sizeof(data[0]), numverts, data );
+ glNormalPointerEXT( GL_FLOAT, sizeof(data[0]), numverts, &data[0][3]);
+ }
+ else
+ {
+ glVertexPointerEXT( 3, GL_FLOAT, sizeof(data[0]), numuniq,
+ compressed_data );
+ glNormalPointerEXT( GL_FLOAT, sizeof(data[0]), numuniq,
+ &compressed_data[0][3]);
+ }
+#ifdef GL_EXT_compiled_vertex_array
+ if (m & COMPILED) {
+ glLockArraysEXT( 0, numuniq );
+ } else {
+ glUnlockArraysEXT();
+ }
+#endif
+ }
+#endif
+
+ if (m & (RENDER_STYLE_MASK|PRIMITIVE_MASK)) {
+ UPDATE(state, m, (RENDER_STYLE_MASK|PRIMITIVE_MASK));
+ }
+
+ if (m & MATERIAL_MASK) {
+ UPDATE(state, m, MATERIAL_MASK);
+ }
+
+ glutPostRedisplay();
+}
+
+
+
+static void Init(void)
+{
+ glClearColor(0.0, 0.0, 0.0, 0.0);
+ glEnable( GL_DEPTH_TEST );
+ glEnable( GL_VERTEX_ARRAY_EXT );
+ glEnable( GL_NORMAL_ARRAY_EXT );
+
+ InitMaterials();
+
+ glMatrixMode(GL_PROJECTION);
+ glLoadIdentity();
+ glFrustum( -1.0, 1.0, -1.0, 1.0, 5, 25 );
+
+ glMatrixMode(GL_MODELVIEW);
+ glLoadIdentity();
+ glClipPlane(GL_CLIP_PLANE0, plane);
+
+ set_matrix();
+
+ glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);
+ glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_FASTEST);
+
+ glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_SPHERE_MAP);
+ glTexGeni(GL_T, GL_TEXTURE_GEN_MODE, GL_SPHERE_MAP);
+
+ if (!LoadRGBMipmaps(TEXTURE_FILE, GL_RGB)) {
+ printf("Error: couldn't load texture image\n");
+ exit(1);
+ }
+
+ if (allowed & COMPILED) {
+ compactify_arrays();
+ make_tri_indices();
+ }
+
+ ModeMenu(SHADE_SMOOTH|
+ LIT|
+ NO_TEXTURE|
+ NO_REFLECT|
+ POINT_FILTER|
+ NOT_COMPILED|
+ NO_USER_CLIP|
+ NO_MATERIALS|
+ IMMEDIATE);
+}
+
+
+
+static void Reshape(int width, int height)
+{
+ glViewport(0, 0, (GLint)width, (GLint)height);
+}
+
+
+
+static void Key( unsigned char key, int x, int y )
+{
+ switch (key) {
+ case 27:
+ exit(0);
+ case 's':
+ ModeMenu((state ^ SHADE_MASK) & SHADE_MASK);
+ break;
+ case 'l':
+ ModeMenu((state ^ LIGHT_MASK) & LIGHT_MASK);
+ break;
+ case 'm':
+ ModeMenu((state ^ MATERIAL_MASK) & MATERIAL_MASK);
+ break;
+ case 'c':
+ ModeMenu((state ^ CLIP_MASK) & CLIP_MASK);
+ break;
+ case 'b':
+ Benchmark(5.0, 0);
+ break;
+ case 'B':
+ Benchmark(0, 5.0);
+ break;
+ case '-':
+ case '_':
+ plane[3] += 2.0;
+ glMatrixMode(GL_MODELVIEW);
+ glLoadIdentity();
+ glClipPlane(GL_CLIP_PLANE0, plane);
+ set_matrix();
+ glutPostRedisplay();
+ break;
+ case '+':
+ case '=':
+ plane[3] -= 2.0;
+ glMatrixMode(GL_MODELVIEW);
+ glLoadIdentity();
+ glClipPlane(GL_CLIP_PLANE0, plane);
+ set_matrix();
+ glutPostRedisplay();
+ break;
+
+ }
+}
+
+
+static void SpecialKey( int key, int x, int y )
+{
+ switch (key) {
+ case GLUT_KEY_LEFT:
+ yrot -= 15.0;
+ break;
+ case GLUT_KEY_RIGHT:
+ yrot += 15.0;
+ break;
+ case GLUT_KEY_UP:
+ xrot += 15.0;
+ break;
+ case GLUT_KEY_DOWN:
+ xrot -= 15.0;
+ break;
+ default:
+ return;
+ }
+ set_matrix();
+ glutPostRedisplay();
+}
+
+
+
+static GLint Args(int argc, char **argv)
+{
+ GLint i;
+ GLint mode = 0;
+
+ 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 {
+ printf("%s (Bad option).\n", argv[i]);
+ return QUIT;
+ }
+ }
+
+ return mode;
+}
+
+int main(int argc, char **argv)
+{
+ GLenum type;
+ char *extensions;
+
+ GLuint arg_mode = Args(argc, argv);
+
+ if (arg_mode & QUIT)
+ exit(0);
+
+ read_surface( "isosurf.dat" );
+
+ glutInitWindowPosition(0, 0);
+ glutInitWindowSize(400, 400);
+
+ type = GLUT_DEPTH;
+ type |= GLUT_RGB;
+ type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
+ glutInitDisplayMode(type);
+
+ if (glutCreateWindow("Isosurface") <= 0) {
+ exit(0);
+ }
+
+ /* Make sure server supports the vertex array extension */
+ extensions = (char *) glGetString( GL_EXTENSIONS );
+
+ if (!strstr( extensions, "GL_EXT_vertex_array" ))
+ {
+ printf("Vertex arrays not supported by this renderer\n");
+ allowed &= ~(COMPILED|DRAW_ARRAYS|ARRAY_ELT);
+ }
+ else if (!strstr( extensions, "GL_EXT_compiled_vertex_array" ))
+ {
+ printf("Compiled vertex arrays not supported by this renderer\n");
+ allowed &= ~COMPILED;
+ }
+
+ Init();
+ ModeMenu(arg_mode);
+
+ glutCreateMenu(ModeMenu);
+ glutAddMenuEntry("Lit", LIT|NO_TEXTURE|NO_REFLECT);
+ glutAddMenuEntry("Unlit", UNLIT|NO_TEXTURE|NO_REFLECT);
+/* glutAddMenuEntry("Textured", TEXTURE); */
+ glutAddMenuEntry("Reflect", TEXTURE|REFLECT);
+ glutAddMenuEntry("", 0);
+ glutAddMenuEntry("Smooth", SHADE_SMOOTH);
+ glutAddMenuEntry("Flat", SHADE_FLAT);
+ glutAddMenuEntry("", 0);
+ glutAddMenuEntry("Point Filtered", POINT_FILTER);
+ glutAddMenuEntry("Linear Filtered", LINEAR_FILTER);
+ glutAddMenuEntry("", 0);
+ glutAddMenuEntry("Immediate (STRIPS)", NOT_COMPILED|IMMEDIATE|STRIPS);
+ glutAddMenuEntry("Immediate (TRIANGLES)", NOT_COMPILED|IMMEDIATE|TRIANGLES);
+ glutAddMenuEntry("", 0);
+ if (allowed & DRAW_ARRAYS) {
+ glutAddMenuEntry("DrawArrays (STRIPS)",
+ NOT_COMPILED|DRAW_ARRAYS|STRIPS);
+ glutAddMenuEntry("ArrayElement (STRIPS)",
+ NOT_COMPILED|ARRAY_ELT|STRIPS);
+ glutAddMenuEntry("DrawElements (TRIANGLES)",
+ NOT_COMPILED|DRAW_ARRAYS|TRIANGLES);
+ glutAddMenuEntry("ArrayElement (TRIANGLES)",
+ NOT_COMPILED|ARRAY_ELT|TRIANGLES);
+ glutAddMenuEntry("", 0);
+
+ }
+ if (allowed & COMPILED) {
+ glutAddMenuEntry("Compiled DrawElements (TRIANGLES)",
+ COMPILED|DRAW_ARRAYS|TRIANGLES);
+ glutAddMenuEntry("Compiled DrawElements (STRIPS)",
+ COMPILED|DRAW_ARRAYS|STRIPS);
+ glutAddMenuEntry("Compiled ArrayElement",
+ COMPILED|ARRAY_ELT|STRIPS);
+ glutAddMenuEntry("", 0);
+ }
+ glutAddMenuEntry("Quit", QUIT);
+ glutAttachMenu(GLUT_RIGHT_BUTTON);
+
+ glutReshapeFunc(Reshape);
+ glutKeyboardFunc(Key);
+ glutSpecialFunc(SpecialKey);
+ glutDisplayFunc(Display);
+ glutMainLoop();
+ return 0;
+}