v3_add( pa, (v3f){0, -max_dist * 2.0f, 0}, pb );
vg_line( pa, pb, 0xff000000 );
v3f n;
float t;
if( spherecast_world( world, pa, pb,
v3_add( pa, (v3f){0, -max_dist * 2.0f, 0}, pb );
vg_line( pa, pb, 0xff000000 );
v3f n;
float t;
if( spherecast_world( world, pa, pb,