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#include "config.h"
#include "arrays.h"
#include "point.h"
#include "vector.h"
#include "eval.h"
#include "object.h"
#include "matrix.h"
static struct object * new_object(int kind, struct closure c)
{
struct object * o = arena_alloc(sizeof(struct object));
o->kind = kind;
o->surf = c;
o->world2obj = o->obj2world = mid;
o->max_scale_applied = 1.0;
o->radius = BS_NOT_COMPUTED;
return o;
}
struct object * cone(struct closure c)
{ return new_object(Cone, c); }
struct object * cube(struct closure c)
{ return new_object(Cube, c); }
struct object * cylinder(struct closure c)
{ return new_object(Cylinder, c); }
struct object * plane(struct closure c)
{ return new_object(Plane, c); }
struct object * sphere(struct closure c)
{ return new_object(Sphere, c); }
static struct object * transform(struct object * o,
struct matrix * t,
struct matrix * tinv,
flt scale)
{
struct object * no = arena_alloc(sizeof(struct object));
no->kind = o->kind;
switch (o->kind) {
case Union:
case Intersection:
case Difference:
no->o1 = transform(o->o1, t, tinv, scale);
no->o2 = transform(o->o2, t, tinv, scale);
break;
default:
no->surf = o->surf;
no->world2obj = mcompose(o->world2obj, tinv);
no->obj2world = mcompose(t, o->obj2world);
no->max_scale_applied = o->max_scale_applied * scale;
}
no->radius = BS_NOT_COMPUTED;
return no;
}
struct object * orotatex(struct object * o1, flt a)
{
return transform(o1, mrotatex(a), mrotatex(-a), 1.0);
}
struct object * orotatey(struct object * o1, flt a)
{
return transform(o1, mrotatey(a), mrotatey(-a), 1.0);
}
struct object * orotatez(struct object * o1, flt a)
{
return transform(o1, mrotatez(a), mrotatez(-a), 1.0);
}
struct object * oscale(struct object * o1, flt sx, flt sy, flt sz)
{
flt scale = sx;
if (sy > scale) scale = sy;
if (sz > scale) scale = sz;
return transform(o1, mscale(sx, sy, sz), mscale(1 / sx, 1 / sy, 1 / sz),
scale);
}
struct object * otranslate(struct object * o1,
flt tx, flt ty, flt tz)
{
return transform(o1, mtranslate(tx, ty, tz), mtranslate(- tx, - ty, - tz),
1.0);
}
struct object * ouscale(struct object * o1, flt s)
{
flt sinv = 1 / s;
return transform(o1, mscale(s, s, s), mscale(sinv, sinv, sinv), s);
}
struct object * odifference(struct object * o1, struct object * o2)
{
struct object * o = arena_alloc(sizeof(struct object));
o->kind = Difference;
o->o1 = o1;
o->o2 = o2;
o->radius = BS_NOT_COMPUTED;
return o;
}
struct object * ointersect(struct object * o1, struct object * o2)
{
struct object * o = arena_alloc(sizeof(struct object));
o->kind = Intersection;
o->o1 = o1;
o->o2 = o2;
o->radius = BS_NOT_COMPUTED;
return o;
}
struct object * ounion(struct object * o1, struct object * o2)
{
struct object * o = arena_alloc(sizeof(struct object));
o->kind = Union;
o->o1 = o1;
o->o2 = o2;
o->radius = BS_NOT_COMPUTED;
return o;
}
static void normal_vector_object(struct object * obj,
struct point * p,
int face,
/*out*/ struct vector * v)
{
switch (obj->kind) {
case Cone:
if (face == 0) {
v->dx = p->x; v->dy = - p->y; v->dz = p->z;
} else {
v->dx = 0; v->dy = 1; v->dz = 0;
}
break;
case Cube:
switch (face) {
case 0:
v->dx = 0; v->dy = 0; v->dz = -1; break;
case 1:
v->dx = 0; v->dy = 0; v->dz = 1; break;
case 2:
v->dx = -1; v->dy = 0; v->dz = 0; break;
case 3:
v->dx = 1; v->dy = 0; v->dz = 0; break;
case 4:
v->dx = 0; v->dy = 1; v->dz = 0; break;
case 5:
v->dx = 0; v->dy = -1; v->dz = 0; break;
}
break;
case Cylinder:
switch (face) {
case 0:
v->dx = p->x; v->dy = 0; v->dz = p->z; break;
case 1:
v->dx = 0; v->dy = 1; v->dz = 0; break;
case 2:
v->dx = 0; v->dy = -1; v->dz = 0; break;
}
break;
case Plane:
v->dx = 0; v->dy = 1; v->dz = 0; break;
case Sphere:
v->dx = p->x; v->dy = p->y; v->dz = p->z; break;
default:
assert(0);
}
}
static void tangent_vectors(struct vector * n,
/*out*/ struct vector * t1,
/*out*/ struct vector * t2)
{
if (n->dy > 0) {
t1->dx = n->dy; t1->dy = - n->dx; t1->dz = 0;
t2->dx = 0; t2->dy = n->dz; t2->dz = - n->dy;
}
/* y 0 xy x
-x ^ z = yy = y y
0 -y yz z */
else if (n->dy == 0) {
t1->dx = n->dz; t1->dy = 0; t1->dz = - n->dx;
t2->dx = n->dz; t2->dy = 1; t2->dz = - n->dx;
}
/* z z x x
0 ^ 1 = 0 = 1 y
-x -x z z */
else {
t1->dx = n->dy; t1->dy = - n->dx; t1->dz = 0;
t2->dx = 0; t2->dy = - n->dz; t2->dz = n->dy;
}
/* y 0 -xy x
-x ^ -z = -yy = (-y) y
0 y -zy z */
}
void normal_vector(struct object * obj, struct point * p, int face,
/*out*/ struct vector * n)
{
struct point pobj;
struct vector nobj, tang_obj1, tang_obj2, tang_world1, tang_world2;
apply_to_point(obj->world2obj, p, &pobj);
normal_vector_object(obj, &pobj, face, &nobj);
tangent_vectors(&nobj, &tang_obj1, &tang_obj2);
apply_to_vect(obj->obj2world, &tang_obj1, &tang_world1);
apply_to_vect(obj->obj2world, &tang_obj2, &tang_world2);
product(&tang_world1, &tang_world2, n);
vnormalize(n, n);
}
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