Circle buffer and png cleaning.

src/core/data_structures/CircleBuffer.h

@@ -0,0 +1,64 @@
+#pragma once
+
+#include <vector>
+
+#include <iostream>
+
+template<typename T>
+class CircleBuffer
+{
+public:
+    CircleBuffer(std::size_t size)
+        : mData(size)
+    {
+
+    }
+
+    void addItem(const T& item)
+    {
+        if (mEndPointer < mData.size())
+        {
+            mData[mEndPointer] = item;
+            mEndPointer++;
+        }
+        else
+        {
+            mData[mStartPointer] = item;
+            if (mStartPointer < mData.size() - 1)
+            {
+                mStartPointer++;
+            }
+            else
+            {
+                mStartPointer = 0;
+            }
+        }
+    }
+
+    std::size_t getNumItems() const
+    {
+        return mEndPointer;
+    }
+
+    const T& getItem(std::size_t index) const
+    {
+        if (mEndPointer < mData.size())
+        {
+            return mData[index];
+        }
+        else
+        {
+            auto offset = mStartPointer + index;
+            if (offset >= mData.size())
+            {
+                offset -= mData.size();
+            }
+            return mData[offset];
+        }
+    }
+
+private:
+    std::size_t mStartPointer{0};
+    std::size_t mEndPointer{0};
+    std::vector<T> mData;
+};