ENTRYPOINT void
init_gears (ModeInfo *mi)
{
gears_configuration *bp;
int wire = MI_IS_WIREFRAME(mi);
int i;
if (!bps) {
bps = (gears_configuration *)
calloc (MI_NUM_SCREENS(mi), sizeof (gears_configuration));
if (!bps) {
fprintf(stderr, "%s: out of memory\n", progname);
exit(1);
}
}
bp = &bps[MI_SCREEN(mi)];
bp->glx_context = init_GL(mi);
reshape_gears (mi, MI_WIDTH(mi), MI_HEIGHT(mi));
if (!wire)
{
GLfloat pos[4] = {1.0, 1.0, 1.0, 0.0};
GLfloat amb[4] = {0.0, 0.0, 0.0, 1.0};
GLfloat dif[4] = {1.0, 1.0, 1.0, 1.0};
GLfloat spc[4] = {0.0, 1.0, 1.0, 1.0};
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
glEnable(GL_DEPTH_TEST);
glEnable(GL_CULL_FACE);
glLightfv(GL_LIGHT0, GL_POSITION, pos);
glLightfv(GL_LIGHT0, GL_AMBIENT, amb);
glLightfv(GL_LIGHT0, GL_DIFFUSE, dif);
glLightfv(GL_LIGHT0, GL_SPECULAR, spc);
}
{
double spin_speed = 0.5;
double wander_speed = 0.01;
double spin_accel = 0.25;
bp->rot = make_rotator (do_spin ? spin_speed : 0,
do_spin ? spin_speed : 0,
do_spin ? spin_speed : 0,
spin_accel,
do_wander ? wander_speed : 0,
True
);
bp->trackball = gltrackball_init ();
}
if (!(random() % 8))
{
planetary_gears (mi);
}
else
{
gear *g = 0;
int total_gears = MI_COUNT (mi);
int i;
if (total_gears <= 0)
total_gears = 3 + abs (BELLRAND (8) - 4); /* 3 - 7, mostly 3. */
bp->gears = (gear **) calloc (total_gears+2, sizeof(**bp->gears));
bp->ngears = 0;
for (i = 0; i < total_gears; i++)
g = place_new_gear (mi, g);
}
/* Center gears in scene. */
{
GLfloat minx=99999, miny=99999, maxx=-99999, maxy=-99999;
int i;
for (i = 0; i < bp->ngears; i++)
{
gear *g = bp->gears[i];
if (g->x - g->r < minx) minx = g->x - g->r;
if (g->x + g->r > maxx) maxx = g->x + g->r;
if (g->y - g->r < miny) miny = g->y - g->r;
if (g->y + g->r > maxy) maxy = g->y + g->r;
}
bp->bbox.x1 = minx;
bp->bbox.y1 = miny;
bp->bbox.x2 = maxx;
bp->bbox.y2 = maxy;
}
/* Now render each gear into its display list.
*/
for (i = 0; i < bp->ngears; i++)
{
gear *g = bp->gears[i];
g->dlist = glGenLists (1);
if (! g->dlist)
{
check_gl_error ("glGenLists");
abort();
}
glNewList (g->dlist, GL_COMPILE);
g->polygons += draw_involute_gear (g, wire);
glEndList ();
}
if (bp->planetary_p)
armature (mi);
}
/* Render one gear in the proper position, creating the gear's
display list first if necessary.
*/
static void
draw_gear (ModeInfo *mi, int which)
{
Bool wire_p = MI_IS_WIREFRAME(mi);
pinion_configuration *pp = &pps[MI_SCREEN(mi)];
gear *g = pp->gears[which];
GLfloat th;
Bool visible_p = (g->x + g->r + g->tooth_h >= pp->render_left &&
g->x - g->r - g->tooth_h <= pp->render_right);
if (!visible_p && !debug_p)
return;
if (! g->dlist)
{
g->dlist = glGenLists (1);
if (! g->dlist)
{
/* I don't know how many display lists a GL implementation
is supposed to provide, but hopefully it's more than
"a few hundred", or we'll be in trouble...
*/
check_gl_error ("glGenLists");
abort();
}
glNewList (g->dlist, GL_COMPILE);
g->polygons = draw_involute_gear (g, (wire_p && debug_p ? 2 : wire_p));
glEndList ();
}
glPushMatrix();
glTranslatef (g->x, g->y, g->z);
if (g->motion_blur_p && !pp->button_down_p)
{
/* If we're in motion-blur mode, then draw the gear so that each
frame rotates it by exactly one half tooth-width, so that it
looks flickery around the edges. But, revert to the normal
way when the mouse button is down lest the user see overlapping
polygons.
*/
th = g->motion_blur_p * 180.0 / g->nteeth * (g->th > 0 ? 1 : -1);
g->motion_blur_p++;
}
else
th = g->th;
glRotatef (th, 0, 0, 1);
glPushName (g->id);
if (! visible_p)
mi->polygon_count += draw_involute_schematic (g, wire_p);
else
{
glCallList (g->dlist);
mi->polygon_count += g->polygons;
}
glPopName();
glPopMatrix();
}
ENTRYPOINT void
init_mgears (ModeInfo *mi)
{
mgears_configuration *bp;
int wire = MI_IS_WIREFRAME(mi);
int i;
if (!bps) {
bps = (mgears_configuration *)
calloc (MI_NUM_SCREENS(mi), sizeof (mgears_configuration));
if (!bps) {
fprintf(stderr, "%s: out of memory\n", progname);
exit(1);
}
}
bp = &bps[MI_SCREEN(mi)];
bp->glx_context = init_GL(mi);
reshape_mgears (mi, MI_WIDTH(mi), MI_HEIGHT(mi));
if (!wire)
{
GLfloat pos[4] = {1.0, 1.0, 1.0, 0.0};
GLfloat amb[4] = {0.0, 0.0, 0.0, 1.0};
GLfloat dif[4] = {1.0, 1.0, 1.0, 1.0};
GLfloat spc[4] = {0.0, 1.0, 1.0, 1.0};
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
glEnable(GL_DEPTH_TEST);
glEnable(GL_CULL_FACE);
glLightfv(GL_LIGHT0, GL_POSITION, pos);
glLightfv(GL_LIGHT0, GL_AMBIENT, amb);
glLightfv(GL_LIGHT0, GL_DIFFUSE, dif);
glLightfv(GL_LIGHT0, GL_SPECULAR, spc);
}
{
double spin_speed = 0.5;
double wander_speed = 0.01;
double spin_accel = 2.0;
bp->rot = make_rotator (do_spin ? spin_speed : 0,
do_spin ? spin_speed : 0,
do_spin ? spin_speed : 0,
spin_accel,
do_wander ? wander_speed : 0,
False /* don't randomize */
);
bp->trackball = gltrackball_init ();
}
{
int total_gears = MI_COUNT(mi);
double gears_per_turn;
double gear_r, tw, th, thick, slope;
int nubs, size;
if (! (total_gears & 1))
total_gears++; /* must be odd or gears intersect */
/* Number of teeth must be odd if number of gears is odd, or teeth don't
mesh when the loop closes. And since number of gears must be odd...
*/
if (! (teeth_arg & 1)) teeth_arg++;
if (teeth_arg < 7) teeth_arg = 7;
if (total_gears < 13) /* gear mesh angle is too steep with less */
total_gears = 13;
thick = 0.2;
nubs = (random() & 3) ? 0 : (random() % teeth_arg) / 2;
slope = 0;
/* Sloping gears are incompatible with "-roll" ... */
/* slope= -M_PI * 2 / total_gears; */
gears_per_turn = total_gears / 2.0;
bp->ring_r = 3;
gear_r = M_PI * bp->ring_r / gears_per_turn;
tw = 0;
th = gear_r * 2.5 / teeth_arg;
/* If the gears are small, use a lower density mesh. */
size = (gear_r > 0.32 ? INVOLUTE_LARGE :
gear_r > 0.13 ? INVOLUTE_MEDIUM :
INVOLUTE_SMALL);
/* If there are lots of teeth, use a lower density mesh. */
if (teeth_arg > 77)
size = INVOLUTE_SMALL;
if (teeth_arg > 45 && size == INVOLUTE_LARGE)
size = INVOLUTE_MEDIUM;
bp->ngears = total_gears;
bp->gears = (mogear *) calloc (bp->ngears, sizeof(*bp->gears));
for (i = 0; i < bp->ngears; i++)
{
mogear *mg = &bp->gears[i];
gear *g = &mg->g;
g->r = gear_r;
g->size = size;
g->nteeth = teeth_arg;
g->tooth_w = tw;
g->tooth_h = th;
g->tooth_slope = slope;
g->thickness = g->r * thick;
g->thickness2 = g->thickness * 0.1;
g->thickness3 = g->thickness;
g->inner_r = g->r * 0.80;
g->inner_r2 = g->r * 0.60;
g->inner_r3 = g->r * 0.55;
g->nubs = nubs;
mg->pos_th = (M_PI * 2 / gears_per_turn) * i;
mg->pos_thz = (M_PI / 2 / gears_per_turn) * i;
g->th = ((i & 1)
? (M_PI * 2 / g->nteeth)
: 0);
/* Colorize
*/
g->color[0] = 0.7 + frand(0.3);
g->color[1] = 0.7 + frand(0.3);
g->color[2] = 0.7 + frand(0.3);
g->color[3] = 1.0;
g->color2[0] = g->color[0] * 0.85;
g->color2[1] = g->color[1] * 0.85;
g->color2[2] = g->color[2] * 0.85;
g->color2[3] = g->color[3];
/* Now render the gear into its display list.
*/
g->dlist = glGenLists (1);
if (! g->dlist)
{
check_gl_error ("glGenLists");
abort();
}
glNewList (g->dlist, GL_COMPILE);
g->polygons += draw_involute_gear (g, wire);
glEndList ();
}
}
}
