void update_friction(int n)
{
// kill lateral velocity
const cpFloat max_lateral_impulse = 300;
cpVect impulse = cpvmult(cpvneg(lateral_velocity(n)), cpBodyGetMass(tire[n]));
//printf("%f\n", cpvlength(impulse));
if(cpvlength(impulse) > max_lateral_impulse)
impulse = cpvmult(impulse, max_lateral_impulse / cpvlength(impulse));
cpBodyApplyImpulse(tire[n], impulse, cpvzero);
// TODO - kill angular velocity?
cpFloat inertia = cpBodyGetMoment(tire[n]);
cpFloat av = cpBodyGetAngVel(tire[n]);
if(av != 0)
cpBodySetAngVel(tire[n], av / 1.2);
// apply drag
cpVect forward_normal = forward_velocity(n);
cpFloat forward_speed = cpvlength(forward_normal);
if(forward_speed < 1) {
cpBodySetVel(tire[n], cpvzero);
} else {
forward_normal = cpvnormalize(forward_normal);
cpFloat drag = -1 * forward_speed;
cpBodyApplyImpulse(tire[n], cpvmult(forward_normal, drag), cpvzero);
}
}
void update_drive()
{
const cpFloat max_forward_speed = 150;
const cpFloat max_backward_speed = -20;
const cpFloat max_drive_force = 100;
int i;
for(i=0; i<1; i++) {
cpFloat desired_speed = 0;
// find desired speed
if(controls.forward)
desired_speed = max_forward_speed;
else if(controls.back)
desired_speed = max_backward_speed;
// find speed
cpVect forward_normal = cpvperp(cpvforangle(cpBodyGetAngle(tire[i])));
cpFloat speed = cpvdot(forward_velocity(i), forward_normal);
// apply force
cpFloat force = 0;
if(desired_speed > speed)
force = max_drive_force;
else if(desired_speed < speed)
force = -max_drive_force;
else
return;
cpBodyApplyImpulse(tire[i], cpvmult(forward_normal, force), cpvzero);
}
}
void camera_t::calc_velocity(float dt) {
glm::vec3 forward_velocity(dir * dt * speed),
strafing_velocity(right * dt * speed);
static bool prev_move_foward = false, prev_move_right = false;
if (user[FORWARD] || user[BACK] || user[LEFT] || user[RIGHT]) {
speed += dt * 75.0f; // TODO: fix scaling issue
speed = glm::clamp(speed, 0.0f, 64.0f);
} else {
// apply momentum...
speed *= 0.97f;
if (strafing == false) {
pos += (forward_velocity * ((prev_move_foward) ? 1.0f : -1.0f));
}
if (moving_back_or_forth == false) {
pos += (strafing_velocity * ((prev_move_right) ? 1.0f : -1.0f));
}
}
if (user[FORWARD]) {
pos += forward_velocity;
prev_move_foward = true;
} else if (user[BACK]) {
pos -= forward_velocity;
prev_move_foward = false;
}
if (user[RIGHT]) {
pos += strafing_velocity;
prev_move_right = true;
} else if (user[LEFT]) {
pos -= strafing_velocity;
prev_move_right = false;
}
}
