43 lines
1.1 KiB
C
43 lines
1.1 KiB
C
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#include "math.h"
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#include "object.h"
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#include <cglm/cglm.h>
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float frand48(void) {
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float number = (float) rand() / (float) (RAND_MAX + 1.0);
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float side = rand() % 2;
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if (side == 0) {
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number = -number;
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}
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return number;
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}
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void calculate_gravity(struct object *src, struct object *target, vec3 force) {
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vec4 tmp;
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glm_vec4_sub(target->position, src->position, tmp);
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vec3 distance;
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glm_vec3(tmp, distance);
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float distance_xy = sqrt((distance[0] * distance[0]) + (distance[1] * distance[1]));
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float distance_xyz = sqrt((distance_xy * distance_xy) + (distance[2] * distance[2]));
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float force_scale = 4.0f;
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float g = 6.67f * 1e-11f;
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float top = g * src->mass * target->mass;
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for (int i = 0; i < 3; i++) {
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distance[i] = (distance[i] * distance[i] * distance[i]);
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}
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for (int i = 0; i < 3; i++) {
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if (distance[i] == 0) {
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force[i] = 0.0f;
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continue;
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}
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force[i] = (top / (distance_xyz / (target->position[i] - src->position[i]))) * force_scale;
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}
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}
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