Class: CP::DampedSpring

Inherits:
Object
  • Object
show all
Includes:
Constraint
Defined in:
lib/chipmunk-ffi/constraints/damped_spring.rb

Constant Summary

Constants included from Constraint

Constraint::DampedRotarySpring, Constraint::DampedSpring, Constraint::GearJoint, Constraint::GrooveJoint, Constraint::PinJoint, Constraint::PivotJoint, Constraint::RatchetJoint, Constraint::RotaryLimitJoint, Constraint::SimpleMotor, Constraint::SlideJoint

Instance Attribute Summary

Attributes included from Constraint

#body_a, #body_b, #struct

Instance Method Summary collapse

Methods included from Constraint

included, #set_data_pointer

Constructor Details

#initialize(a_body, b_body, anchr_one, anchr_two, rest_length, stiffness, damping) ⇒ DampedSpring

Returns a new instance of DampedSpring.



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# File 'lib/chipmunk-ffi/constraints/damped_spring.rb', line 26

def initialize(a_body, b_body, anchr_one, anchr_two, 
               rest_length, stiffness, damping)
  @body_a, @body_b = a_body, b_body
  @struct = DampedSpringStruct.new(CP.cpDampedSpringNew(
    a_body.struct.pointer,b_body.struct.pointer,anchr_one.struct,anchr_two.struct,
    rest_length, stiffness, damping))
  set_data_pointer
  set_initial_force_proc
end

Instance Method Details

#spring_force_func ⇒ Object 



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# File 'lib/chipmunk-ffi/constraints/damped_spring.rb', line 36

def spring_force_func
  @user_level_force_lambda
end

#spring_force_func=(l) ⇒ Object 



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# File 'lib/chipmunk-ffi/constraints/damped_spring.rb', line 40

def spring_force_func=(l)
  @user_level_force_lambda = l
  
  # We keep the lambda in an ivar to keep it from being GCed
  @spring_force_lambda = Proc.new do |spring_ptr,dist|
    spring_struct = DampedSpringStruct.new(spring_ptr)
    obj_id = spring_struct.constraint.data.get_long(0)
    spring = ObjectSpace._id2ref(obj_id)
    l.call(spring,dist)
  end
  @struct.spring_force_func = @spring_force_lambda
end