6 files changed, 35 insertions, 9 deletions
diff --git a/include/brain/bias_node.h b/include/brain/bias_node.h
new file mode 100644
index 0000000..501a0a0
--- /dev/null
+++ b/include/brain/bias_node.h
@@ -0,0 +1,10 @@
+#pragma once
+
+#include "brain/neural_node.h"
+
+class BiasNode: public NeuralNode
+{
+public:
+    BiasNode();
+    virtual double activation() const { return 1; }
+};
diff --git a/include/brain/neural_link.h b/include/brain/neural_link.h
index 447b26f..42ee2f9 100644
--- a/include/brain/neural_link.h
+++ b/include/brain/neural_link.h
@@ -7,7 +7,8 @@
 class NeuralLink
 {
 public:
-    double weightedActivation();
+    NeuralLink(double weight);
+    double weightedActivation() const;
     
 private:
     std::shared_ptr<NeuralNode> _input;
diff --git a/include/brain/neural_network.h b/include/brain/neural_network.h
index 37eb3a1..bb53079 100644
--- a/include/brain/neural_network.h
+++ b/include/brain/neural_network.h
@@ -15,8 +15,8 @@ public:
     void setInput(int inputIndex, double activation);
     int findMaxOutputIndex();
 
-    int numberOfSensors() { return _sensors.size(); }
-    int numberOfOutputs() { return _outputs.size(); }
+    int numberOfSensors() const { return _sensors.size(); }
+    int numberOfOutputs() const { return _outputs.size(); }
 	
 private:
     std::vector<std::shared_ptr<NeuralNode>> _nodes;
diff --git a/include/brain/neural_node.h b/include/brain/neural_node.h
index abc27b8..3c2a6cb 100644
--- a/include/brain/neural_node.h
+++ b/include/brain/neural_node.h
@@ -3,5 +3,14 @@
 class NeuralNode
 {
 public:
-    virtual double activation() = 0;
+    NeuralNode(char type, int id);
+    virtual ~NeuralNode() {};
+	
+    virtual double activation() const = 0;
+    
+    char type() const { return _type; }
+    int id() const { return _id; }
+private:
+    char _type;
+    int _id;
 };
diff --git a/include/brain/neuron.h b/include/brain/neuron.h
index 27d7202..1607cf0 100644
--- a/include/brain/neuron.h
+++ b/include/brain/neuron.h
@@ -9,8 +9,11 @@
 class Neuron : public NeuralNode
 {
 public:
-    virtual double activation() {}
+    Neuron(int id);
+    virtual ~Neuron() {}
+    virtual double activation() const;
 
 private:
     std::vector<std::shared_ptr<NeuralLink>> _inputLinks;
+    double sigmoid(double input) const;
 };
diff --git a/include/brain/sensor.h b/include/brain/sensor.h
index 06b96d0..b33080b 100644
--- a/include/brain/sensor.h
+++ b/include/brain/sensor.h
@@ -4,10 +4,13 @@
 
 class Sensor: public NeuralNode
 {
-private:
-    double _activation;
-    
 public:
+    Sensor(int id);
+    virtual ~Sensor() {}
+    
     void setActivation(double activation) { _activation = activation; }
-    virtual double activation() { return _activation; }
+    virtual double activation() const { return _activation; }
+    
+private:
+    double _activation;
 };