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 * modification, are permitted provided that the following conditions are
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 *
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 * notice, this list of conditions and the following disclaimer.
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 * in the documentation and/or other materials provided with the
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// This file contains the implementation of Function.

#include "core/cross/function.h"

namespace o3d {

O3D_DEFN_CLASS(FunctionContext, ObjectBase);
O3D_DEFN_CLASS(Function, NamedObject);
O3D_DEFN_CLASS(ParamFunction, RefParamBase);
O3D_DEFN_CLASS(FunctionEval, ParamObject);

FunctionContext::FunctionContext(ServiceLocator* service_locator)
    : ObjectBase(service_locator) {
}

Function::Function(ServiceLocator* service_locator)
    : NamedObject(service_locator),
      weak_pointer_manager_(this) {
}

const char* FunctionEval::kInputParamName =
    O3D_STRING_CONSTANT("input");
const char* FunctionEval::kFunctionObjectParamName =
    O3D_STRING_CONSTANT("functionObject");
const char* FunctionEval::kOutputParamName =
    O3D_STRING_CONSTANT("output");

FunctionEval::FunctionEval(ServiceLocator* service_locator)
    : ParamObject(service_locator),
      function_context_(NULL) {
  RegisterParamRef(kInputParamName, &input_param_);
  RegisterParamRef(kFunctionObjectParamName, &function_object_param_);
  SlaveParamFloat::RegisterParamRef(kOutputParamName,
                                    &output_param_,
                                    this);
}

void FunctionEval::UpdateOutputs() {
  if (output_param_->input_connection() == NULL) {
    Function* function = function_object_param_->value();
    if (function) {
      // If we don't have a function context or if the one we have is the wrong
      // type then get a new one.
      if (!function_context_ ||
          !function_context_->IsA(function->GetFunctionContextClass())) {
        function_context_.Reset();
        function_context_ = FunctionContext::Ref(
            function->CreateFunctionContext());
      }
      output_param_->set_dynamic_value(
          function->Evaluate(input_param_->value(), function_context_.Get()));
    } else {
      output_param_->set_dynamic_value(input_param_->value());
    }
  }
}

ObjectBase::Ref FunctionEval::Create(ServiceLocator* service_locator) {
  return ObjectBase::Ref(new FunctionEval(service_locator));
}

ObjectBase::Ref ParamFunction::Create(ServiceLocator* service_locator) {
  return ObjectBase::Ref(new ParamFunction(service_locator, false, false));
}

}  // namespace o3d