SqaureGame/obj/target.c

71 lines
2.1 KiB
C

#include "header.h"
#include <raymath.h>
#include <math.h>
// Target is circular, thus a kinematic obj has w=h
struct target_obj init_target(){
return (struct target_obj){
.radius = 12,
.kinematic = init_kinematic_obj(12, 12)
};
}
bool collide_target(struct kinematic_obj *obj, struct target_obj *target){
/* The method is based off SAT
*/
Vector2 obj_center = center(obj->rect);
Vector2 target_center = center(target->kinematic.rect);
float dist = Vector2Distance(obj_center, target_center);
if (dist < target->radius)
return true;
double max_dim = fmax(obj->rect.width, obj->rect.height);
if (dist > max_dim + target->radius)
return false;
Vector2 n = Vector2Subtract(target_center, obj_center);
n = Vector2Normalize(n);
Vector2 pos_check = obj->pos;
double obj_proj1 = Vector2DotProduct(pos_check, n);
pos_check.x += obj->rect.width;
double obj_proj2 = Vector2DotProduct(pos_check, n);
pos_check.y += obj->rect.height;
double obj_proj3 = Vector2DotProduct(pos_check, n);
pos_check.x -= obj->rect.width;
double obj_proj4 = Vector2DotProduct(pos_check, n);
double min_proj = fmin(fmin(fmin(obj_proj1, obj_proj2), obj_proj3), obj_proj4);
double max_proj = fmax(fmax(fmax(obj_proj1, obj_proj2), obj_proj3), obj_proj4);
double target_proj = Vector2DotProduct(target_center, n);
if (!(max_proj < target_proj - target->radius) && !(min_proj > target_proj + target->radius))
return true;
return false;
}
void add_target_node(struct target_obj *obj, struct target_obj_node **HEAD){
struct target_obj_node *node = malloc(sizeof(struct target_obj_node));
if (node){
node->obj = obj;
node->next = NULL;
}
if (*HEAD != NULL)
node->next = *HEAD;
*HEAD = node;
}
void free_target_list(struct target_obj_node **HEAD){
struct target_obj_node *current = *HEAD;
struct target_obj_node *next;
while(current){
next = current->next;
current->next = NULL;
free(current);
current = next;
}
*HEAD = NULL;
}