#import "camera.h"
#import "memory.h"
#import "gl_headers.h"

camera *new_camera(graphics_settings settings)
{
    camera *new = autorelease(alloc(sizeof(camera)));
    new->eye = make_vector(0, 0, -10);
    new->focus = zero_vector;
    new->up = make_vector(0, 1, 0);
    return new;
}


void look_at_by_rotating(camera *c, vector what)
{
    c->focus = what;
}

void look_at_by_translating(camera *c, vector what)
{
    vector distance = vec_sub(what, c->focus);
    c->eye = vec_add(c->eye, distance);
    c->focus = what;
}

void move_eye(camera *c, vector delta)
{
    c->eye = vec_add(c->eye, delta);
}

void move_focus(camera *c, vector delta)
{
    look_at_by_rotating(c, vec_add(c->focus, delta));
}

void move_camera(camera *c, vector delta)
{
    look_at_by_translating(c, vec_add(c->focus, delta));
}


void apply_camera(camera *c)
{
    gluLookAt(UNPACK_VECTOR(c->eye), UNPACK_VECTOR(c->focus), UNPACK_VECTOR(c->up));
}