Cube  Check-in [da90479adf]

#define FONTH 64
#define PIXELTAB (VIRTW / 12)

#define PI (3.1415927f)
#define PI2 (2 * PI)

// simplistic vector ops
#define dotprod(u, v) ((u).x * (v).x + (u).y * (v).y + (u).z * (v).z)
#define vdist(d, v, e, s)                         \
	OFVector3D v = OFSubtractVectors3D(s, e); \
	float d = (float)sqrt(dotprod(v, v));
	float d = sqrtf(OFDotProductOfVectors3D(v, v));
#define vreject(v, u, max)                                 \
	((v).x > (u).x + (max) || (v).x < (u).x - (max) || \
	    (v).y > (u).y + (max) || (v).y < (u).y - (max))
#define vlinterp(v, f, u, g)                   \
	{                                      \
		(v).x = (v).x * f + (u).x * g; \
		(v).y = (v).y * f + (u).y * g; \

static bool
intersect(DynamicEntity *d, const OFVector3D *from, const OFVector3D *to)
{
	OFVector3D v = *to, w = d.origin;
	const OFVector3D *p;
	v = OFSubtractVectors3D(v, *from);
	w = OFSubtractVectors3D(w, *from);
	float c1 = dotprod(w, v);
	float c1 = OFDotProductOfVectors3D(w, v);

	if (c1 <= 0)
		p = from;
	else {
		float c2 = dotprod(v, v);
		float c2 = OFDotProductOfVectors3D(v, v);
		if (c2 <= c1)
			p = to;
		else {
			v = OFMultiplyVector3D(v, c1 / c2);
			v = OFAddVectors3D(v, *from);
			p = &v;
		}