/* geodesicgears, Copyright (c) 2014-2015 Jamie Zawinski <jwz@jwz.org>
*
* Permission to use, copy, modify, distribute, and sell this software and its
* documentation for any purpose is hereby granted without fee, provided that
* the above copyright notice appear in all copies and that both that
* copyright notice and this permission notice appear in supporting
* documentation. No representations are made about the suitability of this
* software for any purpose. It is provided "as is" without express or
* implied warranty.
*
* Inspired by http://bugman123.com/Gears/
* and by http://kennethsnelson.net/PortraitOfAnAtom.pdf
*/
#define DEFAULTS "*delay: 30000 \n" \
"*count: 4 \n" \
"*wireframe: False \n" \
"*showFPS: False \n" \
"*texFontCacheSize: 100 \n" \
"*suppressRotationAnimation: True\n" \
"*font: -*-helvetica-medium-r-normal-*-*-160-*-*-*-*-*-*\n" \
# define release_geodesic 0
#undef countof
#define countof(x) (sizeof((x))/sizeof((*x)))
#include "xlockmore.h"
#include "involute.h"
#include "colors.h"
#include "normals.h"
#include "rotator.h"
#include "gltrackball.h"
#include <ctype.h>
#include "texfont.h"
#ifdef USE_GL /* whole file */
#include "gllist.h"
#define DEF_SPIN "True"
#define DEF_WANDER "True"
#define DEF_SPEED "1.0"
#define DEF_LABELS "False"
#define DEF_NUMBERS "False"
#define DEF_TIMEOUT "20"
typedef struct { double a, o; } LL; /* latitude + longitude */
/* 10:6 is a mismesh. */
static const struct {
enum { PRISM, OCTO, DECA, G14, G18, G32, G92, G182 } type;
const GLfloat args[5];
} gear_templates[] = {
{ PRISM },
{ OCTO },
{ DECA },
{ G14 },
{ G18 },
{ G32, { 15, 6, 0.4535 }}, /* teeth1, teeth2, radius1 */
{ G32, { 15, 12, 0.3560 }},
{ G32, { 20, 6, 0.4850 }},
{ G32, { 20, 12, 0.3995 }}, /* double of 10:6 */
{ G32, { 20, 18, 0.3375 }},
{ G32, { 25, 6, 0.5065 }},
{ G32, { 25, 12, 0.4300 }},
{ G32, { 25, 18, 0.3725 }},
{ G32, { 25, 24, 0.3270 }},
{ G32, { 30, 12, 0.4535 }}, /* double of 15:6 */
{ G32, { 30, 18, 0.3995 }},
{ G32, { 30, 24, 0.3560 }}, /* double of 15:12 */
{ G32, { 30, 30, 0.3205 }},
{ G32, { 35, 12, 0.4710 }},
{ G32, { 35, 18, 0.4208 }},
{ G32, { 35, 24, 0.3800 }},
{ G32, { 35, 30, 0.3450 }},
{ G32, { 35, 36, 0.3160 }},
{ G32, { 40, 12, 0.4850 }}, /* double of 20:6 */
{ G32, { 40, 24, 0.3995 }}, /* double of 10:6, 20:12 */
/*{ G32, { 40, 36, 0.3375 }},*/ /* double of 20:18 */
{ G32, { 50, 12, 0.5065 }}, /* double of 25:6 */
{ G32, { 50, 24, 0.4300 }}, /* double of 25:12 */
/* These all have phase errors and don't always mesh properly.
Maybe we should just omit them? */
{ G92, { 35, 36, 16, 0.2660, 0.366 }}, /* teeth1, 2, 3, r1, pitch3 */
{ G92, { 25, 36, 11, 0.2270, 0.315 }},
/*{ G92, { 15, 15, 8, 0.2650, 0.356 }},*/
/*{ G92, { 20, 21, 8, 0.2760, 0.355 }},*/
{ G92, { 25, 27, 16, 0.2320, 0.359 }},
{ G92, { 20, 36, 11, 0.1875, 0.283 }},
{ G92, { 30, 30, 16, 0.2585, 0.374 }}, /* double of 15:15:8 */
{ G92, { 20, 33, 11, 0.1970, 0.293 }},
/*{ G92, { 10, 12, 8, 0.2030, 0.345 }},*/
{ G92, { 30, 33, 16, 0.2455, 0.354 }},
/*{ G92, { 25, 24, 8, 0.3050, 0.375 }},*/
{ G92, { 20, 24, 16, 0.2030, 0.346 }},
};
typedef struct sphere_gear sphere_gear;
struct sphere_gear {
int id; /* name, for debugging */
XYZ axis; /* the vector on which this gear's axis lies */
int direction; /* rotation, +1 or -1 */
GLfloat offset; /* rotational degrees from parent gear */
sphere_gear *parent; /* gear driving this one, or 0 for root */
sphere_gear **children; /* gears driven by this one (no loops) */
sphere_gear **neighbors; /* gears touching this one (circular!) */
int nchildren, children_size;
int nneighbors, neighbors_size;
const gear *g; /* shape of this gear (shared) */
};
typedef struct {
GLXContext *glx_context;
rotator *rot;
trackball_state *trackball;
Bool button_down_p;
int ncolors;
XColor *colors;
GLfloat color1[4], color2[4];
texture_font_data *font;
int nshapes, shapes_size; /* how many 'gear' objects there are */
int ngears, gears_size; /* how many 'sphere_gear' objects there are */
gear *shapes;
sphere_gear *gears;
int which;
int mode; /* 0 = normal, 1 = out, 2 = in */
int mode_tick;
int next; /* 0 = random, -1 = back, 1 = forward */
time_t draw_time;
int draw_tick;
char *desc;
GLfloat th; /* rotation of the root sphere_gear in degrees. */
} geodesic_configuration;
static geodesic_configuration *bps = NULL;
static int timeout;
static Bool do_spin;
static GLfloat speed;
static Bool do_wander;
static Bool do_labels;
static Bool do_numbers;
static XrmOptionDescRec opts[] = {
{ "-spin", ".spin", XrmoptionNoArg, "True" },
{ "+spin", ".spin", XrmoptionNoArg, "False" },
{ "-speed", ".speed", XrmoptionSepArg, 0 },
{ "-wander", ".wander", XrmoptionNoArg, "True" },
{ "+wander", ".wander", XrmoptionNoArg, "False" },
{ "-labels", ".labels", XrmoptionNoArg, "True" },
{ "+labels", ".labels", XrmoptionNoArg, "False" },
{ "-numbers", ".numbers",XrmoptionNoArg, "True" },
{ "+numbers", ".numbers",XrmoptionNoArg, "False" },
{ "-timeout", ".timeout",XrmoptionSepArg, 0 },
};
static argtype vars[] = {
{&do_spin, "spin", "Spin", DEF_SPIN, t_Bool},
{&do_wander, "wander", "Wander", DEF_WANDER, t_Bool},
{&speed, "speed", "Speed", DEF_SPEED, t_Float},
{&do_labels, "labels", "Labels", DEF_LABELS, t_Bool},
{&do_numbers,"numbers","Numbers",DEF_NUMBERS,t_Bool},
{&timeout, "timeout","Seconds",DEF_TIMEOUT,t_Int},
};
ENTRYPOINT ModeSpecOpt geodesic_opts = {
countof(opts), opts, countof(vars), vars, NULL};
#undef BELLRAND
#define BELLRAND(n) ((frand((n)) + frand((n)) + frand((n))) / 3)
static XYZ
cross_product (XYZ a, XYZ b)
{
XYZ c;
c.x = (a.y * b.z) - (a.z * b.y);
c.y = (a.z * b.x) - (a.x * b.z);
c.z = (a.x * b.y) - (a.y * b.x);
return c;
}
static GLfloat
dot_product (XYZ a, XYZ b)
{
return (a.x * b.x) + (a.y * b.y) + (a.z * b.z);
}
static XYZ
normalize (XYZ v)
{
GLfloat d = sqrt ((v.x * v.x) + (v.y * v.y) + (v.z * v.z));
if (d == 0)
v.x = v.y = v.z = 0;
else
{
v.x /= d;
v.y /= d;
v.z /= d;
}
return v;
}
static XYZ
polar_to_cartesian (LL v)
{
XYZ p;
p.x = cos (v.a) * cos (v.o);
p.y = cos (v.a) * sin (v.o);
p.z = sin (v.a);
return p;
}
static gear *
add_gear_shape (ModeInfo *mi, GLfloat radius, int teeth)
{
geodesic_configuration *bp = &bps[MI_SCREEN(mi)];
int wire = MI_IS_WIREFRAME(mi);
gear *g;
int i;
if (bp->nshapes >= bp->shapes_size - 1)
{
bp->shapes_size = bp->shapes_size * 1.2 + 4;
bp->shapes = (gear *)
realloc (bp->shapes, bp->shapes_size * sizeof(*bp->shapes));
}
g = &bp->shapes[bp->nshapes++];
memset (g, 0, sizeof(*g));
g->r = radius;
g->nteeth = teeth;
g->ratio = 1;
g->tooth_h = g->r / (teeth * 0.4);
if (g->tooth_h > 0.06) /* stubbier teeth when small tooth count. */
g->tooth_h *= 0.6;
g->thickness = 0.05 + BELLRAND(0.15);
g->thickness2 = g->thickness / 4;
g->thickness3 = g->thickness;
g->size = wire ? INVOLUTE_SMALL : INVOLUTE_LARGE;
/* Move the disc's origin inward to make the edge of the disc be tangent
to the unit sphere. */
g->z = 1 - sqrt (1 - (g->r * g->r));
/* #### This isn't quite right */
g->tooth_slope = 1 + ((g->z * 2) / g->r);
/* Decide on shape of gear interior:
- just a ring with teeth;
- that, plus a thinner in-set "plate" in the middle;
- that, plus a thin raised "lip" on the inner plate;
- or, a wide lip (really, a thicker third inner plate.)
*/
if (wire)
;
else if ((random() % 10) == 0)
{
/* inner_r can go all the way in; there's no inset disc. */
g->inner_r = (g->r * 0.3) + frand((g->r - g->tooth_h/2) * 0.6);
g->inner_r2 = 0;
g->inner_r3 = 0;
}
else
{
/* inner_r doesn't go in very far; inner_r2 is an inset disc. */
g->inner_r = (g->r * 0.5) + frand((g->r - g->tooth_h) * 0.4);
g->inner_r2 = (g->r * 0.1) + frand(g->inner_r * 0.5);
g->inner_r3 = 0;
if (g->inner_r2 > (g->r * 0.2))
{
int nn = (random() % 10);
if (nn <= 2)
g->inner_r3 = (g->r * 0.1) + frand(g->inner_r2 * 0.2);
else if (nn <= 7 && g->inner_r2 >= 0.1)
g->inner_r3 = g->inner_r2 - 0.01;
}
}
/* If we have three discs, sometimes make the middle disc be spokes.
*/
if (g->inner_r3 && ((random() % 5) == 0))
{
g->spokes = 2 + BELLRAND (5);
g->spoke_thickness = 1 + frand(7.0);
if (g->spokes == 2 && g->spoke_thickness < 2)
g->spoke_thickness += 1;
}
/* Sometimes add little nubbly bits, if there is room.
*/
if (!wire && g->nteeth > 5)
{
double size = 0;
involute_biggest_ring (g, 0, &size, 0);
if (size > g->r * 0.2 && (random() % 5) == 0)
{
g->nubs = 1 + (random() % 16);
if (g->nubs > 8) g->nubs = 1;
}
}
/* Decide how complex the polygon model should be.
*/
{
double pix = g->tooth_h * MI_HEIGHT(mi); /* approx. tooth size in pixels */
if (pix <= 4) g->size = INVOLUTE_SMALL;
else if (pix <= 8) g->size = INVOLUTE_MEDIUM;
else if (pix <= 30) g->size = INVOLUTE_LARGE;
else g->size = INVOLUTE_HUGE;
}
if (g->inner_r3 > g->inner_r2) abort();
if (g->inner_r2 > g->inner_r) abort();
if (g->inner_r > g->r) abort();
i = random() % bp->ncolors;
g->color[0] = bp->colors[i].red / 65536.0;
g->color[1] = bp->colors[i].green / 65536.0;
g->color[2] = bp->colors[i].blue / 65536.0;
g->color[3] = 1;
i = (i + bp->ncolors / 2) % bp->ncolors;
g->color2[0] = bp->colors[i].red / 65536.0;
g->color2[1] = bp->colors[i].green / 65536.0;
g->color2[2] = bp->colors[i].blue / 65536.0;
g->color2[3] = 1;
g->dlist = glGenLists (1);
glNewList (g->dlist, GL_COMPILE);
#if 1
{
gear G, *g2 = &G;
*g2 = *g;
/* Move the gear inward so that its outer edge is on the disc, instead
of its midpoint. */
g2->z += g2->thickness/2;
/* 'radius' is at the surface but 'g->r' is at the center, so we need
to reverse the slope computation that involute.c does. */
g2->r /= (1 + (g2->thickness * g2->tooth_slope / 2));
glPushMatrix();
glTranslatef(g2->x, g2->y, -g2->z);
/* Line up the center of the point of tooth 0 with "up". */
glRotatef (90, 0, 0, 1);
glRotatef (180, 0, 1, 0);
glRotatef (-360.0 / g2->nteeth / 4, 0, 0, 1);
g->polygons = draw_involute_gear (g2, wire);
glPopMatrix();
}
# else /* draw discs */
{
glPushMatrix();
glTranslatef(g->x, g->y, -g->z);
glLineWidth (2);
glFrontFace (GL_CCW);
glNormal3f(0, 0, 1);
glColor3f(0, 0, 0);
glDisable (GL_LIGHTING);
glBegin(GL_LINES);
glVertex3f (0, 0, 0);
glVertex3f (0, radius, 0);
glEnd();
glColor3f(0.5, 0.5, 0.5);
glBegin(wire ? GL_LINE_LOOP : GL_TRIANGLE_FAN);
{
GLfloat th;
GLfloat step = M_PI * 2 / 128;
/* radius *= 1.005; */
glVertex3f (0, 0, 0);
for (th = 0; th < M_PI * 2 + step; th += step)
{
GLfloat x = cos(th) * radius;
GLfloat y = sin(th) * radius;
glVertex3f (x, y, 0);
}
}
glEnd();
if (!wire) glEnable(GL_LIGHTING);
glPopMatrix();
}
# endif /* 0 */
glEndList ();
return g;
}
static void
add_sphere_gear (ModeInfo *mi, gear *g, XYZ axis)
{
geodesic_configuration *bp = &bps[MI_SCREEN(mi)];
sphere_gear *gg;
int i;
axis = normalize (axis);
/* If there's already a gear on this axis, don't duplicate it. */
for (i = 0; i < bp->ngears; i++)
{
XYZ o = bp->gears[i].axis;
if (o.x == axis.x && o.y == axis.y && o.z == axis.z)
return;
}
if (bp->ngears >= bp->gears_size - 1)
{
bp->gears_size = bp->gears_size * 1.2 + 10;
bp->gears = (sphere_gear *)
realloc (bp->gears, bp->gears_size * sizeof(*bp->gears));
}
gg = &bp->gears[bp->ngears];
memset (gg, 0, sizeof(*gg));
gg->id = bp->ngears;
gg->axis = axis;
gg->direction = 0;
gg->g = g;
bp->ngears++;
}
static void
free_sphere_gears (ModeInfo *mi)
{
geodesic_configuration *bp = &bps[MI_SCREEN(mi)];
int i;
for (i = 0; i < bp->nshapes; i++)
{
if (bp->shapes[i].dlist)
glDeleteLists (bp->shapes[i].dlist, 1);
}
free (bp->shapes);
bp->nshapes = 0;
bp->shapes_size = 0;
bp->shapes = 0;
for (i = 0; i < bp->ngears; i++)
{
sphere_gear *g = &bp->gears[i];
if (g->children)
free (g->children);
if (g->neighbors)
free (g->neighbors);
}
free (bp->gears);
bp->ngears = 0;
bp->gears_size = 0;
bp->gears = 0;
}
/* Is the gear a member of the list?
*/
static Bool
gear_list_member (sphere_gear *g, sphere_gear **list, int count)
{
int i;
for (i = 0; i < count; i++)
if (list[i] == g) return True;
return False;
}
/* Add the gear to the list, resizing it as needed.
*/
static void
gear_list_push (sphere_gear *g,
sphere_gear ***listP,
int *countP, int *sizeP)
{
if (*countP >= (*sizeP) - 1)
{
*sizeP = (*sizeP) * 1.2 + 4;
*listP = (sphere_gear **) realloc (*listP, (*sizeP) * sizeof(**listP));
}
(*listP)[*countP] = g;
(*countP)++;
}
/* Mark child and parent as being mutual neighbors.
*/
static void
link_neighbors (sphere_gear *parent, sphere_gear *child)
{
if (child == parent) abort();
/* Add child to parent's list of neighbors */
if (! gear_list_member (child, parent->neighbors, parent->nneighbors))
{
gear_list_push (child,
&parent->neighbors,
&parent->nneighbors,
&parent->neighbors_size);
/* fprintf(stderr, "neighbor %2d -> %2d (%d)\n", parent->id, child->id,
parent->nneighbors); */
}
/* Add parent to child's list of neighbors */
if (! gear_list_member (parent, child->neighbors, child->nneighbors))
{
gear_list_push (parent,
&child->neighbors,
&child->nneighbors,
&child->neighbors_size);
/* fprintf(stderr, "neighbor %2d <- %2d\n", parent->id, child->id); */
}
}
/* Mark child as having parent, and vice versa.
*/
static void
link_child (sphere_gear *parent, sphere_gear *child)
{
if (child == parent) abort();
if (child->parent) return;
gear_list_push (child,
&parent->children,
&parent->nchildren,
&parent->children_size);
child->parent = parent;
/* fprintf(stderr, "child %2d -> %2d (%d)\n", parent->id, child->id,
parent->nchildren); */
}
static void link_children (sphere_gear *);
static void
link_children (sphere_gear *parent)
{
int i;
# if 1 /* depth first */
for (i = 0; i < parent->nneighbors; i++)
{
sphere_gear *child = parent->neighbors[i];
if (! child->parent)
{
link_child (parent, child);
link_children (child);
}
}
# else /* breadth first */
for (i = 0; i < parent->nneighbors; i++)
{
sphere_gear *child = parent->neighbors[i];
if (! child->parent)
link_child (parent, child);
}
for (i = 0; i < parent->nchildren; i++)
{
sphere_gear *child = parent->children[i];
link_children (child);
}
# endif
}
/* Whether the two gears touch.
*/
static Bool
gears_touch_p (ModeInfo *mi, sphere_gear *a, sphere_gear *b)
{
/* We need to know if the two discs on the surface overlap.
Find the angle between the axis of each disc, and a point on its edge:
the axis between the hypotenuse and adjacent of a right triangle between
the disc's radius and the origin.
R
_____
|_| /
| /
1 | /
|t/ t = asin(R)
|/
Find the angle between the axes of the two discs.
|
| / angle = acos (v1 dot v2)
1 | / axis = v1 cross v2
| / 1
| /
|/
If the sum of the first two angles is less than the third angle,
they touch.
*/
XYZ p1 = a->axis;
XYZ p2 = b->axis;
double t1 = asin (a->g->r);
double t2 = asin (b->g->r);
double th = acos (dot_product (p1, p2));
return (t1 + t2 >= th);
}
/* Set the rotation direction for the gear and its kids.
*/
static void
orient_gears (ModeInfo *mi, sphere_gear *g)
{
int i;
if (g->parent)
g->direction = -g->parent->direction;
for (i = 0; i < g->nchildren; i++)
orient_gears (mi, g->children[i]);
}
/* Returns the global model coordinates of the given tooth of a gear.
*/
static XYZ
tooth_coords (const sphere_gear *s, int tooth)
{
const gear *g = s->g;
GLfloat off = s->offset * (M_PI / 180) * g->ratio * s->direction;
GLfloat th = (tooth * M_PI * 2 / g->nteeth) - off;
XYZ axis;
GLfloat angle;
XYZ from = { 0, 1, 0 };
XYZ to = s->axis;
XYZ p0, p1, p2;
GLfloat x, y, z, C, S, m[4][4];
axis = cross_product (from, to);
angle = acos (dot_product (from, to));
p0 = normalize (axis);
x = p0.x;
y = p0.y;
z = p0.z;
C = cos(angle);
S = sin(angle);
/* this is what glRotatef does */
m[0][0] = x*x * (1 - C) + C;
m[1][0] = x*y * (1 - C) - z*S;
m[2][0] = x*z * (1 - C) + y*S;
m[3][0] = 0;
m[0][1] = y*x * (1 - C) + z*S;
m[1][1] = y*y * (1 - C) + C;
m[2][1] = y*z * (1 - C) - x*S;
m[3][1] = 0;
m[0][2] = x*z * (1 - C) - y*S;
m[1][2] = y*z * (1 - C) + x*S;
m[2][2] = z*z * (1 - C) + C;
m[3][2] = 0;
m[0][3] = 0;
m[1][3] = 0;
m[2][3] = 0;
m[3][3] = 1;
/* The point to transform */
p1.x = g->r * sin (th);
p1.z = g->r * cos (th);
p1.y = 1 - g->z;
p1 = normalize (p1);
/* transformation result */
p2.x = p1.x * m[0][0] + p1.y * m[1][0] + p1.z * m[2][0] + m[3][0];
p2.y = p1.x * m[0][1] + p1.y * m[1][1] + p1.z * m[2][1] + m[3][1];
p2.z = p1.x * m[0][2] + p1.y * m[1][2] + p1.z * m[2][2] + m[3][2];
return p2;
}
/* Returns the number of the tooth of the first gear that is closest
to any tooth of its parent. Also the position of the parent tooth.
*/
static int
parent_tooth (const sphere_gear *s, XYZ *parent)
{
const sphere_gear *s2 = s->parent;
int i, j;
GLfloat min_dist = 99999;
int min_tooth = 0;
XYZ min_parent = { 0, 0, 0 };
if (s2)
for (i = 0; i < s->g->nteeth; i++)
{
XYZ p1 = tooth_coords (s, i);
for (j = 0; j < s2->g->nteeth; j++)
{
XYZ p2 = tooth_coords (s2, j);
XYZ d;
GLfloat dist;
d.x = p1.x - p2.x;
d.y = p1.y - p2.y;
d.z = p1.z - p2.z;
dist = sqrt (d.x*d.x + d.y*d.y + d.z*d.z);
if (dist < min_dist)
{
min_dist = dist;
min_parent = p2;
min_tooth = i;
}
}
}
*parent = min_parent;
return min_tooth;
}
/* Make all of the gear's children's teeth mesh properly.
*/
static void align_gear_teeth (sphere_gear *s);
static void
align_gear_teeth (sphere_gear *s)
{
int i;
XYZ pc;
if (s->parent)
{
/* Iterate this gear's offset until we find a value for it that
minimizes the distance between this gear's parent-pointing
tooth, and the corresponding tooth on the parent.
*/
int pt = parent_tooth (s, &pc);
GLfloat range = 360 / s->g->nteeth;
GLfloat steps = 64;
GLfloat min_dist = 999999;
GLfloat min_off = 0;
GLfloat off;
for (off = -range/2; off < range/2; off += range/steps)
{
XYZ tc, d;
GLfloat dist;
s->offset = off;
tc = tooth_coords (s, pt);
d.x = pc.x - tc.x;
d.y = pc.y - tc.y;
d.z = pc.z - tc.z;
dist = sqrt (d.x*d.x + d.y*d.y + d.z*d.z);
if (dist < min_dist)
{
min_dist = dist;
min_off = off;
}
}
s->offset = min_off;
}
/* Now do the children. We have to do it in parent/child order because
the offset we just computed for the parent affects everyone downstream.
*/
for (i = 0; i < s->nchildren; i++)
align_gear_teeth (s->children[i]);
}
static void
describe_gears (ModeInfo *mi)
{
geodesic_configuration *bp = &bps[MI_SCREEN(mi)];
int gears_per_teeth[1000];
int i;
int lines = 0;
memset (gears_per_teeth, 0, sizeof(gears_per_teeth));
for (i = 0; i < bp->ngears; i++)
gears_per_teeth[bp->gears[i].g->nteeth]++;
if (bp->desc) free (bp->desc);
bp->desc = (char *) malloc (80 * bp->ngears);
*bp->desc = 0;
for (i = 0; i < countof(gears_per_teeth); i++)
if (gears_per_teeth[i])
{
sprintf (bp->desc + strlen(bp->desc),
"%s%d gears with %d teeth",
(lines > 0 ? ",\n" : ""),
gears_per_teeth[i], i);
lines++;
}
if (lines > 1)
sprintf (bp->desc + strlen(bp->desc), ",\n%d gears total", bp->ngears);
strcat (bp->desc, ".");
}
/* Takes the gears and makes an arbitrary DAG of them in order to compute
direction and gear ratios.
*/
static void
sort_gears (ModeInfo *mi)
{
geodesic_configuration *bp = &bps[MI_SCREEN(mi)];
sphere_gear *root = 0;
int i, j;
/* For each gear, compare it against every other gear.
If they touch, mark them as being each others' neighbors.
*/
for (i = 0; i < bp->ngears; i++)
{
sphere_gear *a = &bp->gears[i];
for (j = 0; j < bp->ngears; j++)
{
sphere_gear *b = &bp->gears[j];
if (a == b) continue;
if (gears_touch_p (mi, a, b))
link_neighbors (a, b);
}
}
bp->gears[0].parent = &bp->gears[0]; /* don't give this one a parent */
link_children (&bp->gears[0]);
bp->gears[0].parent = 0;
# if 0
for (i = 0; i < bp->ngears; i++)
{
fprintf (stderr, "%2d: p = %2d; k(%d, %d) = ",
i,
bp->gears[i].parent ? bp->gears[i].parent->id : -1,
bp->gears[i].nneighbors,
bp->gears[i].nchildren);
for (j = 0; j < bp->gears[i].nneighbors; j++)
fprintf (stderr, "%2d ", (int) bp->gears[i].neighbors[j]->id);
fprintf (stderr, "\t\t");
if (j < 5) fprintf (stderr, "\t");
for (j = 0; j < bp->gears[i].nchildren; j++)
fprintf (stderr, "%2d ", (int) bp->gears[i].children[j]->id);
fprintf (stderr,"\n");
}
fprintf (stderr,"\n");
# endif /* 0 */
/* If there is more than one gear with no parent, we fucked up. */
root = 0;
for (i = 0; i < bp->ngears; i++)
{
sphere_gear *g = &bp->gears[i];
if (!g->parent)
root = g;
}
if (! root) abort();
root->direction = 1;
orient_gears (mi, root);
/* If there are any gears with no direction, they aren't reachable. */
for (i = 0; i < bp->ngears; i++)
{
sphere_gear *g = &bp->gears[i];
if (g->direction == 0)
fprintf(stderr,"INTERNAL ERROR: unreachable: %d\n", g->id);
}
align_gear_teeth (root);
describe_gears (mi);
}
/* Create 5 identical gears arranged on the faces of a uniform
triangular prism.
*/
static void
make_prism (ModeInfo *mi)
{
geodesic_configuration *bp = &bps[MI_SCREEN(mi)];
gear *g;
XYZ a;
int i;
int teeth = 4 * (4 + (int) (BELLRAND(20)));
if (teeth % 4) abort(); /* must be a multiple of 4 */
g = add_gear_shape (mi, 0.7075, teeth);
a.x = 0; a.y = 0; a.z = 1;
add_sphere_gear (mi, g, a);
a.z = -1;
add_sphere_gear (mi, g, a);
a.z = 0;
for (i = 0; i < 3; i++)
{
GLfloat th = i * M_PI * 2 / 3;
a.x = cos (th);
a.y = sin (th);
add_sphere_gear (mi, g, a);
}
if (bp->ngears != 5) abort();
}
/* Create 8 identical gears arranged on the faces of an octohedron
(or alternately, arranged on the diagonals of a cube.)
*/
static void
make_octo (ModeInfo *mi)
{
geodesic_configuration *bp = &bps[MI_SCREEN(mi)];
static const XYZ verts[] = {{ -1, -1, -1 },
{ -1, -1, 1 },
{ -1, 1, 1 },
{ -1, 1, -1 },
{ 1, -1, 1 },
{ 1, -1, -1 },
{ 1, 1, -1 },
{ 1, 1, 1 }};
gear *g;
int i;
int teeth = 4 * (4 + (int) (BELLRAND(20)));
if (teeth % 4) abort(); /* must be a multiple of 4 */
g = add_gear_shape (mi, 0.578, teeth);
for (i = 0; i < countof(verts); i++)
add_sphere_gear (mi, g, verts[i]);
if (bp->ngears != 8) abort();
}
/* Create 10 identical gears arranged on the faces of ... something.
I'm not sure what polyhedron is the basis of this.
*/
static void
make_deca (ModeInfo *mi)
{
geodesic_configuration *bp = &bps[MI_SCREEN(mi)];
gear *g;
XYZ a;
int i, j;
int teeth = 4 * (4 + (int) (BELLRAND(15)));
if (teeth % 4) abort(); /* must be a multiple of 4 */
g = add_gear_shape (mi, 0.5415, teeth);
a.x = 0; a.y = 0; a.z = 1;
add_sphere_gear (mi, g, a);
a.z = -1;
add_sphere_gear (mi, g, a);
for (j = -1; j <= 1; j += 2)
{
GLfloat off = (j < 0 ? 0 : M_PI / 4);
LL v;
v.a = j * M_PI * 0.136; /* #### Empirical. What is this? */
for (i = 0; i < 4; i++)
{
v.o = i * M_PI / 2 + off;
a = polar_to_cartesian (v);
add_sphere_gear (mi, g, a);
}
}
if (bp->ngears != 10) abort();
}
/* Create 14 identical gears arranged on the faces of ... something.
I'm not sure what polyhedron is the basis of this.
*/
static void
make_14 (ModeInfo *mi)
{
geodesic_configuration *bp = &bps[MI_SCREEN(mi)];
gear *g;
XYZ a;
int i;
GLfloat r = 0.4610;
int teeth = 6 * (2 + (int) (BELLRAND(4)));
if (teeth % 6) abort(); /* must be a multiple of 6. I think? */
/* mismeshes: 24 30 34 36 42 48 54 60 */
/* North, south */
g = add_gear_shape (mi, r, teeth);
a.x = 0; a.y = 0; a.z = 1;
add_sphere_gear (mi, g, a);
a.z = -1;
add_sphere_gear (mi, g, a);
/* Equator */
a.z = 0;
for (i = 0; i < 4; i++)
{
GLfloat th = i * M_PI * 2 / 4 + (M_PI / 4);
a.x = cos(th);
a.y = sin(th);
add_sphere_gear (mi, g, a);
}
/* The other 8 */
g = add_gear_shape (mi, r, teeth);
for (i = 0; i < 4; i++)
{
LL v;
v.a = M_PI * 0.197; /* #### Empirical. Also, wrong. What is this? */
v.o = i * M_PI * 2 / 4;
a = polar_to_cartesian (v);
add_sphere_gear (mi, g, a);
v.a = -v.a;
a = polar_to_cartesian (v);
add_sphere_gear (mi, g, a);
}
if (bp->ngears != 14) abort();
}
/* Create 18 identical gears arranged on the faces of ... something.
I'm not sure what polyhedron is the basis of this.
*/
static void
make_18 (ModeInfo *mi)
{
geodesic_configuration *bp = &bps[MI_SCREEN(mi)];
gear *g, *g2;
XYZ a;
int i;
GLfloat r = 0.3830;
int sizes[] = { 8, 12, 16, 20 }; /* 10, 14, 18, 26 and 34 don't work */
int teeth = sizes[random() % countof(sizes)] * (1 + (random() % 4));
/* North, south */
g = add_gear_shape (mi, r, teeth);
a.x = 0; a.y = 0; a.z = 1;
add_sphere_gear (mi, g, a);
a.z = -1;
add_sphere_gear (mi, g, a);
/* Equator */
g2 = add_gear_shape (mi, r, teeth);
a.z = 0;
for (i = 0; i < 8; i++)
{
GLfloat th = i * M_PI * 2 / 8 + (M_PI / 4);
a.x = cos(th);
a.y = sin(th);
add_sphere_gear (mi, (i & 1 ? g : g2), a);
}
/* The other 16 */
g = add_gear_shape (mi, r, teeth);
for (i = 0; i < 4; i++)
{
LL v;
v.a = M_PI * 0.25;
v.o = i * M_PI * 2 / 4;
a = polar_to_cartesian (v);
add_sphere_gear (mi, g, a);
v.a = -v.a;
a = polar_to_cartesian (v);
add_sphere_gear (mi, g, a);
}
if (bp->ngears != 18) abort();
}
/* Create 32 gears arranged along a truncated icosahedron:
One gear on each of the 20 faces, and one on each of the 12 vertices.
*/
static void
make_32 (ModeInfo *mi, const GLfloat *args)
{
/* http://bugman123.com/Gears/32GearSpheres/ */
geodesic_configuration *bp = &bps[MI_SCREEN(mi)];
GLfloat th0 = atan (0.5); /* lat division: 26.57 deg */
GLfloat s = M_PI / 5; /* lon division: 72 deg */
int i;
int teeth1 = args[0];
int teeth2 = args[1];
GLfloat r1 = args[2];
GLfloat ratio = teeth2 / (GLfloat) teeth1;
GLfloat r2 = r1 * ratio;
gear *gear1, *gear2;
if (teeth1 % 5) abort();
if (teeth2 % 6) abort();
gear1 = add_gear_shape (mi, r1, teeth1);
gear2 = add_gear_shape (mi, r2, teeth2);
gear2->ratio = 1 / ratio;
{
XYZ a = { 0, 0, 1 };
XYZ b = { 0, 0, -1 };
add_sphere_gear (mi, gear1, a);
add_sphere_gear (mi, gear1, b);
}
for (i = 0; i < 10; i++)
{
GLfloat th1 = s * i;
GLfloat th2 = s * (i+1);
GLfloat th3 = s * (i+2);
LL v1, v2, v3, vc;
XYZ p1, p2, p3, pc, pc2;
v1.a = th0; v1.o = th1;
v2.a = th0; v2.o = th3;
v3.a = -th0; v3.o = th2;
vc.a = M_PI/2; vc.o = th2;
if (! (i & 1)) /* southern hemisphere */
{
v1.a = -v1.a;
v2.a = -v2.a;
v3.a = -v3.a;
vc.a = -vc.a;
}
p1 = polar_to_cartesian (v1);
p2 = polar_to_cartesian (v2);
p3 = polar_to_cartesian (v3);
pc = polar_to_cartesian (vc);
/* Two faces: 123 and 12c. */
add_sphere_gear (mi, gear1, p1); /* left shared point of 2 triangles */
pc2.x = (p1.x + p2.x + p3.x) / 3; /* center of bottom triangle */
pc2.y = (p1.y + p2.y + p3.y) / 3;
pc2.z = (p1.z + p2.z + p3.z) / 3;
add_sphere_gear (mi, gear2, pc2);
pc2.x = (p1.x + p2.x + pc.x) / 3; /* center of top triangle */
pc2.y = (p1.y + p2.y + pc.y) / 3;
pc2.z = (p1.z + p2.z + pc.z) / 3;
add_sphere_gear (mi, gear2, pc2);
}
if (bp->ngears != 32) abort();
}
/* Create 92 gears arranged along a geodesic sphere: 20 + 12 + 60.
(frequency 3v, class-I geodesic tessellation of an icosahedron)
*/
static void
make_92 (ModeInfo *mi, const GLfloat *args)
{
/* http://bugman123.com/Gears/92GearSpheres/ */
geodesic_configuration *bp = &bps[MI_SCREEN(mi)];
GLfloat th0 = atan (0.5); /* lat division: 26.57 deg */
GLfloat s = M_PI / 5; /* lon division: 72 deg */
int i;
int tscale = 2; /* These don't mesh properly, so let's increase the
number of teeth so that it's not so obvious. */
int teeth1 = args[0] * tscale;
int teeth2 = args[1] * tscale;
int teeth3 = args[2] * tscale;
GLfloat r1 = args[3];
GLfloat ratio2 = teeth2 / (GLfloat) teeth1;
GLfloat ratio3 = teeth3 / (GLfloat) teeth2;
GLfloat r2 = r1 * ratio2;
GLfloat r3 = r2 * ratio3;
GLfloat r4 = args[4]; /* #### Empirical. Not sure what its basis is. */
GLfloat r5 = 1 - r4;
gear *gear1, *gear2, *gear3;
gear1 = add_gear_shape (mi, r1, teeth1);
gear2 = add_gear_shape (mi, r2, teeth2);
gear3 = add_gear_shape (mi, r3, teeth3);
gear2->ratio = 1 / ratio2;
gear3->ratio = 1 / ratio3;
{
XYZ a = { 0, 0, 1 };
XYZ b = { 0, 0, -1 };
add_sphere_gear (mi, gear1, a);
add_sphere_gear (mi, gear1, b);
}
for (i = 0; i < 10; i++)
{
GLfloat th1 = s * i;
GLfloat th2 = s * (i+1);
GLfloat th3 = s * (i+2);
LL v1, v2, v3, vc;
XYZ p1, p2, p3, pc, pc2;
v1.a = th0; v1.o = th1;
v2.a = th0; v2.o = th3;
v3.a = -th0; v3.o = th2;
vc.a = M_PI/2; vc.o = th2;
if (! (i & 1)) /* southern hemisphere */
{
v1.a = -v1.a;
v2.a = -v2.a;
v3.a = -v3.a;
vc.a = -vc.a;
}
p1 = polar_to_cartesian (v1);
p2 = polar_to_cartesian (v2);
p3 = polar_to_cartesian (v3);
pc = polar_to_cartesian (vc);
/* Two faces: 123 and 12c. */
add_sphere_gear (mi, gear1, p1); /* left shared point of 2 triangles */
pc2.x = (p1.x + p2.x + p3.x) / 3; /* center of bottom triangle */
pc2.y = (p1.y + p2.y + p3.y) / 3;
pc2.z = (p1.z + p2.z + p3.z) / 3;
add_sphere_gear (mi, gear2, pc2);
pc2.x = (p1.x + p2.x + pc.x) / 3; /* center of top triangle */
pc2.y = (p1.y + p2.y + pc.y) / 3;
pc2.z = (p1.z + p2.z + pc.z) / 3;
add_sphere_gear (mi, gear2, pc2);
/* left edge of bottom triangle, 1/3 in */
pc2.x = p1.x + (p3.x - p1.x) * r4;
pc2.y = p1.y + (p3.y - p1.y) * r4;
pc2.z = p1.z + (p3.z - p1.z) * r4;
add_sphere_gear (mi, gear3, pc2);
/* left edge of bottom triangle, 2/3 in */
pc2.x = p1.x + (p3.x - p1.x) * r5;
pc2.y = p1.y + (p3.y - p1.y) * r5;
pc2.z = p1.z + (p3.z - p1.z) * r5;
add_sphere_gear (mi, gear3, pc2);
/* left edge of top triangle, 1/3 in */
pc2.x = p1.x + (pc.x - p1.x) * r4;
pc2.y = p1.y + (pc.y - p1.y) * r4;
pc2.z = p1.z + (pc.z - p1.z) * r4;
add_sphere_gear (mi, gear3, pc2);
/* left edge of top triangle, 2/3 in */
pc2.x = p1.x + (pc.x - p1.x) * r5;
pc2.y = p1.y + (pc.y - p1.y) * r5;
pc2.z = p1.z + (pc.z - p1.z) * r5;
add_sphere_gear (mi, gear3, pc2);
/* center of shared edge, 1/3 in */
pc2.x = p1.x + (p2.x - p1.x) * r4;
pc2.y = p1.y + (p2.y - p1.y) * r4;
pc2.z = p1.z + (p2.z - p1.z) * r4;
add_sphere_gear (mi, gear3, pc2);
/* center of shared edge, 2/3 in */
pc2.x = p1.x + (p2.x - p1.x) * r5;
pc2.y = p1.y + (p2.y - p1.y) * r5;
pc2.z = p1.z + (p2.z - p1.z) * r5;
add_sphere_gear (mi, gear3, pc2);
}
if (bp->ngears != 92) abort();
}
static void
make_182 (ModeInfo *mi, const GLfloat *args)
{
/* #### TODO: http://bugman123.com/Gears/182GearSpheres/ */
abort();
}
/* Window management, etc
*/
ENTRYPOINT void
reshape_geodesic (ModeInfo *mi, int width, int height)
{
geodesic_configuration *bp = &bps[MI_SCREEN(mi)];
GLfloat h = (GLfloat) height / (GLfloat) width;
int y = 0;
if (width > height * 5) { /* tiny window: show middle */
height = width * 9/16;
y = -height/2;
h = height / (GLfloat) width;
}
glXMakeCurrent(MI_DISPLAY(mi), MI_WINDOW(mi), *(bp->glx_context));
glViewport (0, y, (GLint) width, (GLint) height);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective (30.0, 1/h, 1.0, 100.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
gluLookAt( 0.0, 0.0, 30.0,
0.0, 0.0, 0.0,
0.0, 1.0, 0.0);
# ifdef HAVE_MOBILE /* Keep it the same relative size when rotated. */
{
int o = (int) current_device_rotation();
if (o != 0 && o != 180 && o != -180)
glScalef (1/h, 1/h, 1/h);
}
# endif
glClear(GL_COLOR_BUFFER_BIT);
}
static void
pick_shape (ModeInfo *mi, time_t last)
{
geodesic_configuration *bp = &bps[MI_SCREEN(mi)];
int count = countof (gear_templates);
if (bp->colors)
free (bp->colors);
bp->ncolors = 1024;
bp->colors = (XColor *) calloc(bp->ncolors, sizeof(XColor));
make_smooth_colormap (0, 0, 0,
bp->colors, &bp->ncolors,
False, 0, False);
free_sphere_gears (mi);
if (last == 0)
{
bp->which = random() % count;
}
else if (bp->next < 0)
{
bp->which--;
if (bp->which < 0) bp->which = count-1;
bp->next = 0;
}
else if (bp->next > 0)
{
bp->which++;
if (bp->which >= count) bp->which = 0;
bp->next = 0;
}
else
{
int n = bp->which;
while (n == bp->which)
n = random() % count;
bp->which = n;
}
switch (gear_templates[bp->which].type) {
case PRISM: make_prism (mi); break;
case OCTO: make_octo (mi); break;
case DECA: make_deca (mi); break;
case G14: make_14 (mi); break;
case G18: make_18 (mi); break;
case G32: make_32 (mi, gear_templates[bp->which].args); break;
case G92: make_92 (mi, gear_templates[bp->which].args); break;
case G182: make_182(mi, gear_templates[bp->which].args); break;
default: abort(); break;
}
sort_gears (mi);
}
ENTRYPOINT void
init_geodesic (ModeInfo *mi)
{
geodesic_configuration *bp;
int wire = MI_IS_WIREFRAME(mi);
MI_INIT (mi, bps);
bp = &bps[MI_SCREEN(mi)];
bp->glx_context = init_GL(mi);
reshape_geodesic (mi, MI_WIDTH(mi), MI_HEIGHT(mi));
{
static GLfloat cspec[4] = {1.0, 1.0, 1.0, 1.0};
static const GLfloat shiny = 128.0;
static GLfloat pos[4] = {1.0, 1.0, 1.0, 0.0};
static GLfloat amb[4] = {0.0, 0.0, 0.0, 1.0};
static GLfloat dif[4] = {1.0, 1.0, 1.0, 1.0};
static GLfloat spc[4] = {0.0, 1.0, 1.0, 1.0};
glLightfv(GL_LIGHT0, GL_POSITION, pos);
glLightfv(GL_LIGHT0, GL_AMBIENT, amb);
glLightfv(GL_LIGHT0, GL_DIFFUSE, dif);
glLightfv(GL_LIGHT0, GL_SPECULAR, spc);
glMaterialfv (GL_FRONT, GL_SPECULAR, cspec);
glMateriali (GL_FRONT, GL_SHININESS, shiny);
}
if (! wire)
{
glEnable (GL_DEPTH_TEST);
glEnable (GL_BLEND);
glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glEnable (GL_LIGHTING);
glEnable (GL_LIGHT0);
}
if (! bp->rot)
{
double spin_speed = 0.25 * speed;
double wander_speed = 0.01 * speed;
double spin_accel = 0.2;
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 (True);
}
bp->font = load_texture_font (MI_DISPLAY(mi), "font");
pick_shape (mi, 0);
}
ENTRYPOINT Bool
geodesic_handle_event (ModeInfo *mi, XEvent *event)
{
geodesic_configuration *bp = &bps[MI_SCREEN(mi)];
if (gltrackball_event_handler (event, bp->trackball,
MI_WIDTH (mi), MI_HEIGHT (mi),
&bp->button_down_p))
return True;
else
{
if (event->xany.type == KeyPress)
{
KeySym keysym;
char c = 0;
XLookupString (&event->xkey, &c, 1, &keysym, 0);
if (c == '<' || c == ',' || c == '-' || c == '_' ||
keysym == XK_Left || keysym == XK_Up || keysym == XK_Prior)
{
bp->next = -1;
goto SWITCH;
}
else if (c == '>' || c == '.' || c == '=' || c == '+' ||
keysym == XK_Right || keysym == XK_Down ||
keysym == XK_Next)
{
bp->next = 1;
goto SWITCH;
}
}
if (screenhack_event_helper (MI_DISPLAY(mi), MI_WINDOW(mi), event))
{
SWITCH:
bp->mode = 1;
bp->mode_tick = 4;
return True;
}
}
return False;
}
ENTRYPOINT void
draw_geodesic (ModeInfo *mi)
{
time_t now = time ((time_t *) 0);
int wire = MI_IS_WIREFRAME(mi);
geodesic_configuration *bp = &bps[MI_SCREEN(mi)];
Display *dpy = MI_DISPLAY(mi);
Window window = MI_WINDOW(mi);
if (!bp->glx_context)
return;
glXMakeCurrent(MI_DISPLAY(mi), MI_WINDOW(mi), *(bp->glx_context));
if (bp->draw_time == 0)
{
pick_shape (mi, bp->draw_time);
bp->draw_time = now;
}
else if (bp->mode == 0)
{
if (bp->draw_tick++ > 10)
{
if (bp->draw_time == 0) bp->draw_time = now;
bp->draw_tick = 0;
if (!bp->button_down_p &&
bp->draw_time + timeout <= now)
{
/* randomize every -timeout seconds */
bp->mode = 1; /* go out */
bp->mode_tick = 10 / speed;
bp->draw_time = now;
}
}
}
else if (bp->mode == 1) /* out */
{
if (--bp->mode_tick <= 0)
{
bp->mode_tick = 10 / speed;
bp->mode = 2; /* go in */
pick_shape (mi, bp->draw_time);
bp->draw_time = now;
}
}
else if (bp->mode == 2) /* in */
{
if (--bp->mode_tick <= 0)
bp->mode = 0; /* normal */
}
else
abort();
if (! wire)
glShadeModel(GL_SMOOTH);
glEnable(GL_DEPTH_TEST);
glEnable(GL_NORMALIZE);
glEnable(GL_CULL_FACE);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glPushMatrix ();
{
double x, y, z;
get_position (bp->rot, &x, &y, &z, !bp->button_down_p);
glTranslatef((x - 0.5) * 8,
(y - 0.5) * 8,
(z - 0.5) * 17);
gltrackball_rotate (bp->trackball);
get_rotation (bp->rot, &x, &y, &z, !bp->button_down_p);
glRotatef (x * 360, 1.0, 0.0, 0.0);
glRotatef (y * 360, 0.0, 1.0, 0.0);
glRotatef (z * 360, 0.0, 0.0, 1.0);
}
mi->polygon_count = 0;
glScalef (6, 6, 6);
if (bp->ngears < 14)
glScalef (0.8, 0.8, 0.8); /* make these a little easier to see */
if (bp->mode != 0)
{
GLfloat s = (bp->mode == 1
? bp->mode_tick / (10 / speed)
: ((10 / speed) - bp->mode_tick + 1) / (10 / speed));
glScalef (s, s, s);
}
{
int i;
for (i = 0; i < bp->ngears; i++)
{
const sphere_gear *s = &bp->gears[i];
const gear *g = s->g;
XYZ axis;
XYZ from = { 0, 1, 0 };
XYZ to = s->axis;
GLfloat angle;
GLfloat off = s->offset;
/* If an even number of teeth, offset by 1/2 tooth width. */
if (s->direction > 0 && !(g->nteeth & 1))
off += 360 / g->nteeth / 2;
axis = cross_product (from, to);
angle = acos (dot_product (from, to));
glPushMatrix();
glTranslatef (to.x, to.y, to.z);
glRotatef (angle / M_PI * 180, axis.x, axis.y, axis.z);
glRotatef (-90, 1, 0, 0);
glRotatef(180, 0, 0, 1);
glRotatef ((bp->th - off) * g->ratio * s->direction,
0, 0, 1);
glCallList (g->dlist);
mi->polygon_count += g->polygons;
glPopMatrix();
#if 0
{ /* Draw tooth vectors */
GLfloat r = 1 - g->z;
XYZ pc;
int pt = parent_tooth (s, &pc);
int t;
glDisable(GL_LIGHTING);
glLineWidth (8);
for (t = 0; t < g->nteeth; t++)
{
XYZ p = tooth_coords (s, t);
XYZ p2;
p2.x = (r * s->axis.x + p.x) / 2;
p2.y = (r * s->axis.y + p.y) / 2;
p2.z = (r * s->axis.z + p.z) / 2;
if (t == pt)
glColor3f(1,0,1);
else
glColor3f(0,1,1);
glBegin(GL_LINES);
glVertex3f (p.x, p.y, p.z);
glVertex3f (p2.x, p2.y, p2.z);
glEnd();
}
if (!wire) glEnable(GL_LIGHTING);
glLineWidth (1);
}
#endif
#if 0
{ /* Draw the parent/child DAG */
GLfloat s1 = 1.1;
GLfloat s2 = s->parent ? s1 : 1.5;
GLfloat s3 = 1.0;
XYZ p1 = s->axis;
XYZ p2 = s->parent ? s->parent->axis : p1;
glDisable(GL_LIGHTING);
glColor3f(0,0,1);
glBegin(GL_LINES);
glVertex3f (s1 * p1.x, s1 * p1.y, s1 * p1.z);
glVertex3f (s2 * p2.x, s2 * p2.y, s2 * p2.z);
glVertex3f (s1 * p1.x, s1 * p1.y, s1 * p1.z);
glVertex3f (s3 * p1.x, s3 * p1.y, s3 * p1.z);
glEnd();
if (!wire) glEnable(GL_LIGHTING);
}
#endif
}
/* We need to draw the fonts in a second pass in order to make
transparency (as a result of anti-aliasing) work properly.
*/
if (do_numbers && bp->mode == 0)
for (i = 0; i < bp->ngears; i++)
{
const sphere_gear *s = &bp->gears[i];
const gear *g = s->g;
XYZ axis;
XYZ from = { 0, 1, 0 };
XYZ to = s->axis;
GLfloat angle;
GLfloat off = s->offset;
int w, h, j;
char buf[100];
XCharStruct e;
/* If an even number of teeth, offset by 1/2 tooth width. */
if (s->direction > 0 /* && !(g->nteeth & 1) */)
off += 360 / g->nteeth / 2;
axis = cross_product (from, to);
angle = acos (dot_product (from, to));
glPushMatrix();
glTranslatef(to.x, to.y, to.z);
glRotatef (angle / M_PI * 180, axis.x, axis.y, axis.z);
glRotatef (-90, 1, 0, 0);
glRotatef(180, 0, 0, 1);
glRotatef ((bp->th - off) * g->ratio * s->direction,
0, 0, 1);
glDisable (GL_LIGHTING);
glColor3f(1, 1, 0);
glPushMatrix();
glScalef(0.005, 0.005, 0.005);
sprintf (buf, "%d", i);
texture_string_metrics (bp->font, buf, &e, 0, 0);
w = e.width;
h = e.ascent + e.descent;
glTranslatef (-w/2, -h/2, 0);
print_texture_string (bp->font, buf);
glPopMatrix();
# if 1
for (j = 0; j < g->nteeth; j++) /* Number the teeth */
{
GLfloat ss = 0.08 * g->r / g->nteeth;
GLfloat r = g->r * 0.88;
GLfloat th = M_PI - (j * M_PI * 2 / g->nteeth + M_PI/2);
glPushMatrix();
glTranslatef (r * cos(th), r * sin(th), -g->z + 0.01);
glScalef(ss, ss, ss);
sprintf (buf, "%d", j + 1);
texture_string_metrics (bp->font, buf, &e, 0, 0);
w = e.width;
h = e.ascent + e.descent;
glTranslatef (-w/2, -h/2, 0);
print_texture_string (bp->font, buf);
glPopMatrix();
}
# endif
glPopMatrix();
if (!wire) glEnable(GL_LIGHTING);
}
bp->th += 0.7 * speed; /* Don't mod this to 360 - causes glitches. */
}
if (do_labels && bp->mode == 0)
{
glColor3f (1, 1, 0);
print_texture_label (mi->dpy, bp->font,
mi->xgwa.width, mi->xgwa.height,
1, bp->desc);
}
glPopMatrix ();
if (mi->fps_p) do_fps (mi);
glFinish();
glXSwapBuffers(dpy, window);
}
ENTRYPOINT void
free_geodesic (ModeInfo *mi)
{
geodesic_configuration *bp = &bps[MI_SCREEN(mi)];
if (!bp->glx_context)
return;
glXMakeCurrent(MI_DISPLAY(mi), MI_WINDOW(mi), *(bp->glx_context));
free_texture_font (bp->font);
free (bp->colors);
free_sphere_gears (mi);
if (bp->desc) free (bp->desc);
}
XSCREENSAVER_MODULE_2 ("GeodesicGears", geodesicgears, geodesic)
#endif /* USE_GL */