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#include <vecmath.h>
#include <physics.h>
#include <stdlib.h>

#include "dat.h"

static void mink(Body *a, Body *b, vec2 min, vec2 max);

int
phxaabbcheck(Body *a, Body *b)
{
	vec2 min, max;
	mink(a, b, min, max);
	return min[0] < 0 && max[0] > 0 && min[1] < 0 && max[1] > 0;
}

void
phxaabbresolv(Body *a, Body *b, vec2 p, vec2 n)
{
	vec2 min, max;
	mink(a, b, min, max);

	float hx = fabsf(min[0]) < fabsf(max[0]) ? fabsf(min[0]) : fabsf(max[0]);
	float hy = fabsf(min[1]) < fabsf(max[1]) ? fabsf(min[1]) : fabsf(max[1]);

	if(hx < hy) {
		n[1] = 0.0;
		n[0] = (fabsf(min[0]) < fabsf(max[0]) ? -1.0 : 1.0);
	} else {
		n[0] = 0;
		n[1] = (fabsf(min[1]) < fabsf(max[1]) ? -1.0 : 1.0);
	}
	
	vec2_mul(p, (vec2){ hx, hy }, n);
}


void 
mink(Body *a, Body *b, vec2 min, vec2 max)
{
	float p[2], s[2];
	
	for(int i = 0; i < 2; i++) {
		s[i] = a->size[i] + b->size[i];
		p[i] = a->pos[i] - b->pos[i];
	}
	
	for(int i = 0; i < 2; i++) {
		min[i] = p[i] - s[i];
		max[i] = p[i] + s[i];
	}
}