open_toontown_panda3d/pandatool/src/eggprogs/eggMakeTube.cxx

271 lines
6.9 KiB
C++

/**
* PANDA 3D SOFTWARE
* Copyright (c) Carnegie Mellon University. All rights reserved.
*
* All use of this software is subject to the terms of the revised BSD
* license. You should have received a copy of this license along
* with this source code in a file named "LICENSE."
*
* @file eggMakeTube.cxx
* @author drose
* @date 2003-10-01
*/
#include "eggMakeTube.h"
#include "eggGroup.h"
#include "eggVertexPool.h"
#include "eggVertex.h"
#include "eggPolygon.h"
#include "pointerTo.h"
#include "look_at.h"
/**
*
*/
EggMakeTube::
EggMakeTube() {
set_program_brief("generate a tube or sphere from geometry in an .egg file");
set_program_description
("egg-make-tube generates an egg file representing a \"tube\" model, "
"a cylinder capped on both ends by hemispheres. This is similar "
"in shape to the CollisionCapsule object within Panda.\n\n"
"This program can also generate spheres if you omit -b; in this "
"case, you are generating a degenerate tube of length 0.");
add_option
("a", "x,y,z", 0,
"Specify the first endpoint of the tube.",
&EggWriter::dispatch_double_triple, nullptr, _point_a);
add_option
("b", "x,y,z", 0,
"Specify the second endpoint of the tube.",
&EggWriter::dispatch_double_triple, &_got_point_b, _point_b);
add_option
("r", "radius", 0,
"Specify the radius of the tube. The tube will extend beyond "
"the endpoints in each direction by the amount of radius.",
&EggWriter::dispatch_double, nullptr, &_radius);
add_option
("slices", "count", 0,
"Specify the number of slices appearing radially around the tube.",
&EggWriter::dispatch_int, nullptr, &_num_slices);
add_option
("crings", "count", 0,
"Specify the number of rings appearing in each endcap of the tube.",
&EggWriter::dispatch_int, nullptr, &_num_crings);
add_option
("trings", "count", 0,
"Specify the number of rings appearing in the cylindrical body "
"of the tube.",
&EggWriter::dispatch_int, nullptr, &_num_trings);
_point_a[0] = 0.0;
_point_a[1] = 0.0;
_point_a[2] = 0.0;
_point_b[0] = 0.0;
_point_b[1] = 0.0;
_point_b[2] = 0.0;
_radius = 1.0;
_num_slices = 8;
_num_crings = 4;
_num_trings = 1;
}
/**
*
*/
void EggMakeTube::
run() {
if (!_got_point_b) {
_point_b[0] = _point_a[0];
_point_b[1] = _point_a[1];
_point_b[2] = _point_a[2];
}
// We will generate the vertices in the canonical space (along the y axis),
// then transform it to the desired point.
LVector3d direction(_point_b[0] - _point_a[0],
_point_b[1] - _point_a[1],
_point_b[2] - _point_a[2]);
_length = direction.length();
// First, create an enclosing group and a vertex pool.
_group = new EggGroup("tube");
_data->add_child(_group);
_vpool = new EggVertexPool("tube");
_group->add_child(_vpool);
// Generate the first endcap.
int ri, si;
EggVertex *vtx_1;
EggVertex *vtx_2;
for (ri = 0; ri < _num_crings; ri++) {
vtx_1 = nullptr;
vtx_2 = nullptr;
for (si = 0; si <= _num_slices; si++) {
EggVertex *vtx_3 = calc_sphere1_vertex(ri, si);
EggVertex *vtx_4 = calc_sphere1_vertex(ri + 1, si);
add_polygon(vtx_1, vtx_2, vtx_4, vtx_3);
vtx_1 = vtx_3;
vtx_2 = vtx_4;
}
}
// Now the cylinder sides.
if (_length != 0.0) {
for (ri = 0; ri < _num_trings; ri++) {
vtx_1 = nullptr;
vtx_2 = nullptr;
for (si = 0; si <= _num_slices; si++) {
EggVertex *vtx_3 = calc_tube_vertex(ri, si);
EggVertex *vtx_4 = calc_tube_vertex(ri + 1, si);
add_polygon(vtx_1, vtx_2, vtx_4, vtx_3);
vtx_1 = vtx_3;
vtx_2 = vtx_4;
}
}
}
// And the second endcap.
for (ri = _num_crings - 1; ri >= 0; ri--) {
vtx_1 = nullptr;
vtx_2 = nullptr;
for (si = 0; si <= _num_slices; si++) {
EggVertex *vtx_3 = calc_sphere2_vertex(ri + 1, si);
EggVertex *vtx_4 = calc_sphere2_vertex(ri, si);
add_polygon(vtx_1, vtx_2, vtx_4, vtx_3);
vtx_1 = vtx_3;
vtx_2 = vtx_4;
}
}
// Now transform the vertices out of the canonical position.
LMatrix4d mat;
look_at(mat, direction, LVector3d(0.0, 0.0, 1.0), CS_zup_right);
mat.set_row(3, LPoint3d(_point_a[0], _point_a[1], _point_a[2]));
_group->transform(mat);
write_egg_file();
}
/**
* Calculates a particular vertex on the surface of the first endcap
* hemisphere.
*/
EggVertex *EggMakeTube::
calc_sphere1_vertex(int ri, int si) {
double r = (double)ri / (double)_num_crings;
double s = (double)si / (double)_num_slices;
// Find the point on the rim, based on the slice.
double theta = s * 2.0 * MathNumbers::pi;
double x_rim = cos(theta);
double z_rim = sin(theta);
// Now pull that point in towards the pole, based on the ring.
double phi = r * 0.5 * MathNumbers::pi;
double to_pole = sin(phi);
double x = _radius * x_rim * to_pole;
double y = -_radius * cos(phi);
double z = _radius * z_rim * to_pole;
EggVertex vert;
vert.set_pos(LPoint3d(x, y, z));
return _vpool->create_unique_vertex(vert);
}
/**
* Calculates a vertex on the side of the cylindrical body of the tube.
*/
EggVertex *EggMakeTube::
calc_tube_vertex(int ri, int si) {
double r = (double)ri / (double)_num_trings;
double s = (double)si / (double)_num_slices;
// Find the point on the rim, based on the slice.
double theta = s * 2.0 * MathNumbers::pi;
double x_rim = cos(theta);
double z_rim = sin(theta);
double x = _radius * x_rim;
double y = _length * r;
double z = _radius * z_rim;
EggVertex vert;
vert.set_pos(LPoint3d(x, y, z));
return _vpool->create_unique_vertex(vert);
}
/**
* Calculates a particular vertex on the surface of the second endcap
* hemisphere.
*/
EggVertex *EggMakeTube::
calc_sphere2_vertex(int ri, int si) {
double r = (double)ri / (double)_num_crings;
double s = (double)si / (double)_num_slices;
// Find the point on the rim, based on the slice.
double theta = s * 2.0 * MathNumbers::pi;
double x_rim = cos(theta);
double z_rim = sin(theta);
// Now pull that point in towards the pole, based on the ring.
double phi = r * 0.5 * MathNumbers::pi;
double to_pole = sin(phi);
double x = _radius * x_rim * to_pole;
double y = _length + _radius * cos(phi);
double z = _radius * z_rim * to_pole;
EggVertex vert;
vert.set_pos(LPoint3d(x, y, z));
return _vpool->create_unique_vertex(vert);
}
/**
* Adds the polygon defined by the indicated four vertices to the group. If
* the first vertex is NULL, does nothing.
*/
void EggMakeTube::
add_polygon(EggVertex *a, EggVertex *b, EggVertex *c, EggVertex *d) {
if (a == nullptr) {
return;
}
PT(EggPolygon) poly = new EggPolygon;
poly->add_vertex(a);
if (a != b) {
poly->add_vertex(b);
}
poly->add_vertex(c);
if (c != d) {
poly->add_vertex(d);
}
_group->add_child(poly.p());
}
int main(int argc, char *argv[]) {
EggMakeTube prog;
prog.parse_command_line(argc, argv);
prog.run();
return 0;
}