void RigidBody::ApplyImpulse(Vector3 const& impulse, Vector3 const& point)
{
if(HasInfiniteMass()) return;
Vector3 deltaVelocity = impulse * GetInverseMass();
SetVelocity(GetVelocity() + deltaVelocity);
Vector3 deltaOmega = GetInverseInertialTensor() * (point-GetPosition()).crossProduct(impulse);
SetAngularVelocity(GetAngularVelocity() + deltaOmega);
}
void RigidBody::QueueImpulse(Vector3 const& impulse, Vector3 const& p)
{
if(HasInfiniteMass()) return;
Vector3 deltaVelocity = impulse * GetInverseMass();
m_queuedDeltaVelocity += deltaVelocity;
Vector3 deltaOmega = GetInverseInertialTensor() * (p-GetPosition()).crossProduct(impulse);
m_queuedDeltaAngularVelocity += deltaOmega;
}
void Physics::CalculatePosition(GameObject& obj)
{
if (state != PHYSICS_PAUSE)
{
auto transformComponent = obj.has(Transform);
auto bodyComponent = obj.has(Body);
//accumulate the total force
auto a = gravity + bodyComponent->GetForce()*bodyComponent->GetInverseMass();
auto position = transformComponent->GetPosition() + bodyComponent->GetVelocity()*debugDt;
auto velocity = bodyComponent->GetVelocity() + a*debugDt;
velocity *= std::pow(damping, debugDt);
transformComponent->SetPosition(position);
//Dont set the velocity of the object
if (state != PHYSICS_FORWARD && state != PHYSICS_REVERSE)
{
bodyComponent->SetVelocity(velocity);
}
}
switch (state)
{
case PHYSICS_PLAY:
break;
case PHYSICS_PAUSE:
debugDt = 0.0f;
state = PHYSICS_PAUSE;
break;
case PHYSICS_FORWARD:
debugDt = 0.0f;
state = PHYSICS_PAUSE;
break;
case PHYSICS_REVERSE:
debugDt = 0.0f;
state = PHYSICS_PAUSE;
break;
}
auto draw = true;
ImGui::Begin("Physics", &draw, ImVec2(350, 350), 0.5);
ImGui::Text("Use Space to Toogle play/pause");
ImGui::Text("Left arrow key for previous frame(when paused)");
ImGui::Text("Right arrow key for next frame(when paused)");
ImGui::Text("Use 1 to toogle debug draw");
ImGui::End();
}
void RigidBody2D::AddLinearImpulse(const Vector2& i_impulse)
{
//TODO //CHECK CHECKCHECK CHECKCHECK CHECKCHECK CHECKCHECK CHECKCHECK CHECK
m_linearVelocity += i_impulse * GetInverseMass();
}
