void make_crater_list() {
int j;
float theta;
listnum = glGenLists(1);
glNewList(listnum, GL_COMPILE);
glEnable(GL_CULL_FACE);
glCullFace(GL_BACK);
glColor3f(0.27, 0.3, 0.27);
for(j = 0; j < NUM_CRATERS; j++) {
glPushMatrix();
glTranslatef(x[j], 0.0, y[j]);
glBegin(GL_TRIANGLE_STRIP);
if (BINC * sqrt(x[j]*x[j] + y[j]*y[j]) > 2 * M_PI / 5) {
draw_outside(radius[j], height[j], 2 * M_PI / 5 );
draw_inside(radius[j], height[j], 2 * M_PI / 5);
}
draw_outside(radius[j], height[j], BINC * sqrt(x[j]*x[j] + y[j]*y[j]));
draw_inside(radius[j], height[j], BINC * sqrt(x[j]*x[j] + y[j]*y[j]));
glEnd();
glPopMatrix();
}
do_terrain();
glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
glColor3f(0.05, 0.07, 0.05);
for(j = 0; j < NUM_CRATERS; j++) {
glPushMatrix();
glTranslatef(x[j], 0.0, y[j]);
glBegin(GL_QUADS);
draw_lines(radius[j], height[j], WINC);
glEnd();
glPopMatrix();
}
glEndList();
}
void
gear(int nt, float wd, float ir, float or, float sa, float tp, float tip, int ns, Profile * ip)
{
/**
* nt - number of teeth
* wd - width of gear at teeth
* ir - inside radius absolute scale
* or - radius at outside of wheel (tip of tooth) ratio of ir
* sa - angle of slant of teeth on gear (1 = slant of one whole tooth)
* tp - ratio of tooth in slice of circle (0..1] (1 = teeth are touching at base)
* tip - ratio of tip of tooth (0..tp] (cant be wider that base of tooth)
* ns - number of elements in wheel width profile
* *ip - list of float pairs {start radius, width, ...} (width is ratio to wd)
*
*/
/* gear lying on xy plane, z for width. all normals calulated
(normalized) */
float prev;
int k, t;
/* estimat # times to divide circle */
if (nt <= 0)
circle_subdiv = 64;
else {
/* lowest multiple of number of teeth */
circle_subdiv = nt;
while (circle_subdiv < 64)
circle_subdiv += nt;
}
/* --- draw wheel face --- */
/* draw horzontal, vertical faces for each section. if first
section radius not zero, use wd for 0.. first if ns == 0
use wd for whole face. last width used to edge. */
if (ns <= 0) {
flat_face(0.0, ir, wd);
} else {
/* draw first flat_face, then continue in loop */
if (ip[0].rad > 0.0) {
flat_face(0.0, ip[0].rad * ir, wd);
prev = wd;
t = 0;
} else {
flat_face(0.0, ip[1].rad * ir, ip[0].wid * wd);
prev = ip[0].wid;
t = 1;
}
for (k = t; k < ns; k++) {
if (prev < ip[k].wid) {
draw_inside(prev * wd, ip[k].wid * wd, ip[k].rad * ir);
} else {
draw_outside(prev * wd, ip[k].wid * wd, ip[k].rad * ir);
}
prev = ip[k].wid;
/* - draw to edge of wheel, add final face if needed - */
if (k == ns - 1) {
flat_face(ip[k].rad * ir, ir, ip[k].wid * wd);
/* now draw side to match tooth rim */
if (ip[k].wid < 1.0) {
draw_inside(ip[k].wid * wd, wd, ir);
} else {
draw_outside(ip[k].wid * wd, wd, ir);
}
} else {
flat_face(ip[k].rad * ir, ip[k + 1].rad * ir, ip[k].wid * wd);
}
}
}
/* --- tooth side faces --- */
tooth_side(nt, ir, or, tp, tip, wd);
/* --- tooth hill surface --- */
}