void lljoint_object::test<6>()
{
LLJoint lljoint;
LLVector3 vec3(2.3f,30.f,10.f);
lljoint.setWorldPosition(vec3);
LLVector3 pos = lljoint.getWorldPosition();
ensure("1:setWorldPosition()/getWorldPosition() failed ", (vec3 == pos));
LLVector3 lastPos = lljoint.getLastWorldPosition();
ensure("2:getLastWorldPosition failed ", (vec3 == lastPos));
}
F32 LLPhysicsMotion::calculateVelocity_local()
{
const F32 world_to_model_scale = 100.0f;
LLJoint *joint = mJointState->getJoint();
const LLVector3 position_world = joint->getWorldPosition();
const LLVector3 last_position_world = mPosition_world;
const LLVector3 positionchange_world = (position_world-last_position_world) * world_to_model_scale;
const LLVector3 velocity_world = positionchange_world;
const F32 velocity_local = toLocal(velocity_world);
return velocity_local;
}
// Return TRUE if character has to update visual params.
BOOL LLPhysicsMotion::onUpdate(F32 time)
{
// static FILE *mFileWrite = fopen("c:\\temp\\avatar_data.txt","w");
if (!mParamDriver)
return FALSE;
if (!mLastTime)
{
mLastTime = time;
return FALSE;
}
////////////////////////////////////////////////////////////////////////////////
// Get all parameters and settings
//
const F32 time_delta = time - mLastTime;
// Don't update too frequently, to avoid precision errors from small time slices.
if (time_delta <= .01)
{
return FALSE;
}
// If less than 1FPS, we don't want to be spending time updating physics at all.
if (time_delta > 1.0)
{
mLastTime = time;
return FALSE;
}
// Higher LOD is better. This controls the granularity
// and frequency of updates for the motions.
const F32 lod_factor = LLVOAvatar::sPhysicsLODFactor;
if (lod_factor == 0)
{
return TRUE;
}
LLJoint *joint = mJointState->getJoint();
const F32 behavior_mass = getParamValue("Mass");
const F32 behavior_gravity = getParamValue("Gravity");
const F32 behavior_spring = getParamValue("Spring");
const F32 behavior_gain = getParamValue("Gain");
const F32 behavior_damping = getParamValue("Damping");
const F32 behavior_drag = getParamValue("Drag");
const BOOL physics_test = FALSE; // Enable this to simulate bouncing on all parts.
F32 behavior_maxeffect = getParamValue("MaxEffect");
if (physics_test)
behavior_maxeffect = 1.0f;
// Normalize the param position to be from [0,1].
// We have to use normalized values because there may be more than one driven param,
// and each of these driven params may have its own range.
// This means we'll do all our calculations in normalized [0,1] local coordinates.
const F32 position_user_local = (mParamDriver->getWeight() - mParamDriver->getMinWeight()) / (mParamDriver->getMaxWeight() - mParamDriver->getMinWeight());
//
// End parameters and settings
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
// Calculate velocity and acceleration in parameter space.
//
//const F32 velocity_joint_local = calculateVelocity_local(time_iteration_step);
const F32 velocity_joint_local = calculateVelocity_local();
const F32 acceleration_joint_local = calculateAcceleration_local(velocity_joint_local);
//
// End velocity and acceleration
////////////////////////////////////////////////////////////////////////////////
BOOL update_visuals = FALSE;
// Break up the physics into a bunch of iterations so that differing framerates will show
// roughly the same behavior.
for (F32 time_iteration = 0; time_iteration <= time_delta; time_iteration += TIME_ITERATION_STEP)
{
F32 time_iteration_step = TIME_ITERATION_STEP;
if (time_iteration + TIME_ITERATION_STEP > time_delta)
{
time_iteration_step = time_delta-time_iteration;
}
// mPositon_local should be in normalized 0,1 range already. Just making sure...
const F32 position_current_local = llclamp(mPosition_local,
0.0f,
1.0f);
// If the effect is turned off then don't process unless we need one more update
// to set the position to the default (i.e. user) position.
if ((behavior_maxeffect == 0) && (position_current_local == position_user_local))
{
return update_visuals;
}
////////////////////////////////////////////////////////////////////////////////
// Calculate the total force
//
// Spring force is a restoring force towards the original user-set breast position.
// F = kx
const F32 spring_length = position_current_local - position_user_local;
const F32 force_spring = -spring_length * behavior_spring;
// Acceleration is the force that comes from the change in velocity of the torso.
// F = ma
const F32 force_accel = behavior_gain * (acceleration_joint_local * behavior_mass);
// Gravity always points downward in world space.
// F = mg
const LLVector3 gravity_world(0,0,1);
const F32 force_gravity = (toLocal(gravity_world) * behavior_gravity * behavior_mass);
// Damping is a restoring force that opposes the current velocity.
// F = -kv
const F32 force_damping = -behavior_damping * mVelocity_local;
// Drag is a force imparted by velocity (intuitively it is similar to wind resistance)
// F = .5kv^2
const F32 force_drag = .5*behavior_drag*velocity_joint_local*velocity_joint_local*llsgn(velocity_joint_local);
const F32 force_net = (force_accel +
force_gravity +
force_spring +
force_damping +
force_drag);
//
// End total force
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
// Calculate new params
//
// Calculate the new acceleration based on the net force.
// a = F/m
const F32 acceleration_new_local = force_net / behavior_mass;
static const F32 max_velocity = 100.0f; // magic number, used to be customizable.
F32 velocity_new_local = mVelocity_local + acceleration_new_local*time_iteration_step;
velocity_new_local = llclamp(velocity_new_local,
-max_velocity, max_velocity);
// Temporary debugging setting to cause all avatars to move, for profiling purposes.
if (physics_test)
{
velocity_new_local = sin(time*4.0);
}
// Calculate the new parameters, or remain unchanged if max speed is 0.
F32 position_new_local = position_current_local + velocity_new_local*time_iteration_step;
if (behavior_maxeffect == 0)
position_new_local = position_user_local;
// Zero out the velocity if the param is being pushed beyond its limits.
if ((position_new_local < 0 && velocity_new_local < 0) ||
(position_new_local > 1 && velocity_new_local > 0))
{
velocity_new_local = 0;
}
// Check for NaN values. A NaN value is detected if the variables doesn't equal itself.
// If NaN, then reset everything.
if ((mPosition_local != mPosition_local) ||
(mVelocity_local != mVelocity_local) ||
(position_new_local != position_new_local))
{
position_new_local = 0;
mVelocity_local = 0;
mVelocityJoint_local = 0;
mAccelerationJoint_local = 0;
mPosition_local = 0;
mPosition_world = LLVector3(0,0,0);
}
const F32 position_new_local_clamped = llclamp(position_new_local,
0.0f,
1.0f);
LLDriverParam *driver_param = dynamic_cast<LLDriverParam *>(mParamDriver);
llassert_always(driver_param);
if (driver_param)
{
// If this is one of our "hidden" driver params, then make sure it's
// the default value.
if ((driver_param->getGroup() != VISUAL_PARAM_GROUP_TWEAKABLE) &&
(driver_param->getGroup() != VISUAL_PARAM_GROUP_TWEAKABLE_NO_TRANSMIT))
{
mCharacter->setVisualParamWeight(driver_param,
0,
FALSE);
}
for (LLDriverParam::entry_list_t::iterator iter = driver_param->mDriven.begin();
iter != driver_param->mDriven.end();
++iter)
{
LLDrivenEntry &entry = (*iter);
LLViewerVisualParam *driven_param = entry.mParam;
setParamValue(driven_param,position_new_local_clamped, behavior_maxeffect);
}
}
//
// End calculate new params
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
// Conditionally update the visual params
//
// Updating the visual params (i.e. what the user sees) is fairly expensive.
// So only update if the params have changed enough, and also take into account
// the graphics LOD settings.
// For non-self, if the avatar is small enough visually, then don't update.
const F32 area_for_max_settings = 0.0;
const F32 area_for_min_settings = 1400.0;
const F32 area_for_this_setting = area_for_max_settings + (area_for_min_settings-area_for_max_settings)*(1.0-lod_factor);
const F32 pixel_area = (F32)sqrt(mCharacter->getPixelArea());
const BOOL is_self = (dynamic_cast<LLVOAvatar *>(mCharacter) != NULL && ((LLVOAvatar*)mCharacter)->isSelf());
if ((pixel_area > area_for_this_setting) || is_self)
{
const F32 position_diff_local = llabs(mPositionLastUpdate_local-position_new_local_clamped);
const F32 min_delta = (1.0001f-lod_factor)*0.4f;
if (llabs(position_diff_local) > min_delta)
{
update_visuals = TRUE;
mPositionLastUpdate_local = position_new_local;
}
}
//
// End update visual params
////////////////////////////////////////////////////////////////////////////////
mVelocity_local = velocity_new_local;
mAccelerationJoint_local = acceleration_joint_local;
mPosition_local = position_new_local;
}
mLastTime = time;
mPosition_world = joint->getWorldPosition();
mVelocityJoint_local = velocity_joint_local;
/*
// Write out debugging info into a spreadsheet.
if (mFileWrite != NULL && is_self)
{
fprintf(mFileWrite,"%f\t%f\t%f \t\t%f \t\t%f\t%f\t%f\t \t\t%f\t%f\t%f\t%f\t%f \t\t%f\t%f\t%f\n",
position_new_local,
velocity_new_local,
acceleration_new_local,
time_delta,
mPosition_world[0],
mPosition_world[1],
mPosition_world[2],
force_net,
force_spring,
force_accel,
force_damping,
force_drag,
spring_length,
velocity_joint_local,
acceleration_joint_local
);
}
*/
return update_visuals;
}