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#include "body.h"
#include "test_util.h"
#include <assert.h>
#include <math.h>
#include <stdlib.h>
void test_body_init() {
vector_t v[] = {{1, 1}, {2, 1}, {2, 2}, {1, 2}};
const size_t VERTICES = sizeof(v) / sizeof(*v);
list_t *shape = list_init(0, free);
for (size_t i = 0; i < VERTICES; i++) {
vector_t *list_v = malloc(sizeof(*list_v));
*list_v = v[i];
list_add(shape, list_v);
}
rgb_color_t color = {0, 0.5, 1};
body_t *body = body_init(shape, 3, color);
list_t *shape2 = body_get_shape(body);
assert(list_size(shape2) == VERTICES);
for (size_t i = 0; i < VERTICES; i++) {
assert(vec_isclose(*(vector_t *) list_get(shape2, i), v[i]));
}
list_free(shape2);
assert(vec_isclose(body_get_centroid(body), (vector_t) {1.5, 1.5}));
assert(vec_equal(body_get_velocity(body), VEC_ZERO));
assert(body_get_color(body).r == color.r);
assert(body_get_color(body).g == color.g);
assert(body_get_color(body).b == color.b);
assert(body_get_mass(body) == 3);
body_free(body);
}
void test_body_setters() {
list_t *shape = list_init(3, free);
vector_t *v = malloc(sizeof(*v));
*v = (vector_t) {+1, 0};
list_add(shape, v);
v = malloc(sizeof(*v));
*v = (vector_t) {0, +1};
list_add(shape, v);
v = malloc(sizeof(*v));
*v = (vector_t) {-1, 0};
list_add(shape, v);
body_t *body = body_init(shape, 1, (rgb_color_t) {0, 0, 0});
body_set_velocity(body, (vector_t) {+5, -5});
assert(vec_equal(body_get_velocity(body), (vector_t) {+5, -5}));
assert(vec_isclose(body_get_centroid(body), (vector_t) {0, 1.0 / 3.0}));
body_set_centroid(body, (vector_t) {1, 2});
assert(vec_isclose(body_get_centroid(body), (vector_t) {1, 2}));
shape = body_get_shape(body);
assert(list_size(shape) == 3);
assert(vec_isclose(*(vector_t *) list_get(shape, 0), (vector_t) {2, 5.0 / 3.0}));
assert(vec_isclose(*(vector_t *) list_get(shape, 1), (vector_t) {1, 8.0 / 3.0}));
assert(vec_isclose(*(vector_t *) list_get(shape, 2), (vector_t) {0, 5.0 / 3.0}));
list_free(shape);
body_set_rotation(body, M_PI / 2);
assert(vec_isclose(body_get_centroid(body), (vector_t) {1, 2}));
shape = body_get_shape(body);
assert(list_size(shape) == 3);
assert(vec_isclose(*(vector_t *) list_get(shape, 0), (vector_t) {4.0 / 3.0, 3}));
assert(vec_isclose(*(vector_t *) list_get(shape, 1), (vector_t) {1.0 / 3.0, 2}));
assert(vec_isclose(*(vector_t *) list_get(shape, 2), (vector_t) {4.0 / 3.0, 1}));
list_free(shape);
body_set_centroid(body, (vector_t) {3, 4});
assert(vec_isclose(body_get_centroid(body), (vector_t) {3, 4}));
shape = body_get_shape(body);
assert(list_size(shape) == 3);
assert(vec_isclose(*(vector_t *) list_get(shape, 0), (vector_t) {10.0 / 3.0, 5}));
assert(vec_isclose(*(vector_t *) list_get(shape, 1), (vector_t) {7.0 / 3.0, 4}));
assert(vec_isclose(*(vector_t *) list_get(shape, 2), (vector_t) {10.0 / 3.0, 3}));
list_free(shape);
body_free(body);
}
void test_body_tick() {
const vector_t A = {1, 2};
const double DT = 1e-6;
const int STEPS = 1000000;
list_t *shape = list_init(4, free);
vector_t *v = malloc(sizeof(*v));
v->x = v->y = -1;
list_add(shape, v);
v = malloc(sizeof(*v));
*v = (vector_t) {+1, -1};
list_add(shape, v);
v = malloc(sizeof(*v));
v->x = v->y = +1;
list_add(shape, v);
v = malloc(sizeof(*v));
*v = (vector_t) {-1, +1};
list_add(shape, v);
body_t *body = body_init(shape, 1, (rgb_color_t) {0, 0, 0});
// Apply constant acceleration and ensure position is (a / 2) * t ** 2
for (int i = 0; i < STEPS; i++) {
double t = i * DT;
assert(vec_isclose(body_get_centroid(body), vec_multiply(t * t / 2, A)));
body_set_velocity(body, vec_multiply(t + DT / 2, A));
body_tick(body, DT);
}
double t = STEPS * DT;
vector_t new_x = vec_multiply(t * t / 2, A);
shape = body_get_shape(body);
assert(vec_isclose(*(vector_t *) list_get(shape, 0), vec_add((vector_t) {-1, -1}, new_x)));
assert(vec_isclose(*(vector_t *) list_get(shape, 1), vec_add((vector_t) {+1, -1}, new_x)));
assert(vec_isclose(*(vector_t *) list_get(shape, 2), vec_add((vector_t) {+1, +1}, new_x)));
assert(vec_isclose(*(vector_t *) list_get(shape, 3), vec_add((vector_t) {-1, +1}, new_x)));
list_free(shape);
body_free(body);
}
void test_infinite_mass() {
list_t *shape = list_init(10, free);
vector_t *v = malloc(sizeof(*v));
*v = VEC_ZERO;
list_add(shape, v);
v = malloc(sizeof(*v));
*v = (vector_t) {+1, 0};
list_add(shape, v);
v = malloc(sizeof(*v));
*v = (vector_t) {+1, +1};
list_add(shape, v);
v = malloc(sizeof(*v));
*v = (vector_t) {0, +1};
list_add(shape, v);
body_t *body = body_init(shape, INFINITY, (rgb_color_t) {0, 0, 0});
body_set_velocity(body, (vector_t) {2, 3});
assert(body_get_mass(body) == INFINITY);
body_add_force(body, (vector_t) {1, 1});
body_tick(body, 1.0);
assert(vec_equal(body_get_velocity(body), (vector_t) {2, 3}));
assert(vec_isclose(body_get_centroid(body), (vector_t) {2.5, 3.5}));
body_free(body);
}
void test_forces() {
const double MASS = 10;
const double DT = 0.1;
list_t *shape = list_init(3, free);
vector_t *v = malloc(sizeof(*v));
*v = (vector_t) {+1, 0};
list_add(shape, v);
v = malloc(sizeof(*v));
*v = (vector_t) {0, +1};
list_add(shape, v);
v = malloc(sizeof(*v));
*v = (vector_t) {-1, 0};
list_add(shape, v);
body_t *body = body_init(shape, MASS, (rgb_color_t) {0, 0, 0});
body_set_centroid(body, VEC_ZERO);
vector_t old_velocity = {1, -2};
body_set_velocity(body, old_velocity);
body_add_force(body, (vector_t) {MASS * 3, MASS * 4});
body_add_impulse(body, (vector_t) {MASS * 10, MASS * 5});
body_add_force(body, (vector_t) {MASS * 3, MASS * 4});
body_tick(body, DT);
vector_t new_velocity =
vec_add(old_velocity, (vector_t) {10 + 6 * DT, 5 + 8 * DT});
assert(vec_isclose(body_get_velocity(body), new_velocity));
vector_t new_centroid =
vec_multiply(DT / 2, vec_add(old_velocity, new_velocity));
assert(vec_isclose(body_get_centroid(body), new_centroid));
body_tick(body, DT);
assert(vec_isclose(
body_get_centroid(body),
vec_add(new_centroid, vec_multiply(DT, new_velocity))
));
body_free(body);
}
void test_body_remove() {
list_t *shape = list_init(3, free);
vector_t *v = malloc(sizeof(*v));
*v = (vector_t) {+1, 0};
list_add(shape, v);
v = malloc(sizeof(*v));
*v = (vector_t) {0, +1};
list_add(shape, v);
v = malloc(sizeof(*v));
*v = (vector_t) {-1, 0};
list_add(shape, v);
body_t *body = body_init(shape, 1, (rgb_color_t) {0, 0, 0});
assert(!body_is_removed(body));
body_remove(body);
assert(body_is_removed(body));
body_remove(body);
assert(body_is_removed(body));
body_free(body);
}
void test_body_info() {
list_t *shape = list_init(3, free);
vector_t *v = malloc(sizeof(*v));
*v = (vector_t) {+1, 0};
list_add(shape, v);
v = malloc(sizeof(*v));
*v = (vector_t) {0, +1};
list_add(shape, v);
v = malloc(sizeof(*v));
*v = (vector_t) {-1, 0};
list_add(shape, v);
int *info = malloc(sizeof(*info));
*info = 123;
body_t *body = body_init_with_info(shape, 1, (rgb_color_t) {0, 0, 0}, info, NULL);
assert(*(int *) body_get_info(body) == 123);
body_free(body);
free(info);
}
void test_body_info_freer() {
list_t *shape = list_init(3, free);
vector_t *v = malloc(sizeof(*v));
*v = (vector_t) {+1, 0};
list_add(shape, v);
v = malloc(sizeof(*v));
*v = (vector_t) {0, +1};
list_add(shape, v);
v = malloc(sizeof(*v));
*v = (vector_t) {-1, 0};
list_add(shape, v);
list_t *info = list_init(3, free);
int *info_elem = malloc(sizeof(*info_elem));
*info_elem = 10;
list_add(info, info_elem);
info_elem = malloc(sizeof(*info_elem));
*info_elem = 20;
list_add(info, info_elem);
info_elem = malloc(sizeof(*info_elem));
*info_elem = 30;
list_add(info, info_elem);
body_t *body = body_init_with_info(
shape,
1,
(rgb_color_t) {0, 0, 0},
info,
(free_func_t) list_free
);
assert(*(int *) list_get(body_get_info(body), 0) == 10);
assert(*(int *) list_get(body_get_info(body), 1) == 20);
assert(*(int *) list_get(body_get_info(body), 2) == 30);
body_free(body);
}
int main(int argc, char *argv[]) {
// Run all tests if there are no command-line arguments
bool all_tests = argc == 1;
// Read test name from file
char testname[100];
if (!all_tests) {
read_testname(argv[1], testname, sizeof(testname));
}
DO_TEST(test_body_init)
DO_TEST(test_body_setters)
DO_TEST(test_body_tick)
DO_TEST(test_infinite_mass)
DO_TEST(test_forces)
DO_TEST(test_body_remove)
DO_TEST(test_body_info)
DO_TEST(test_body_info_freer)
puts("body_test PASS");
}