Optimize vertex buffer writing in Debug Draw

Source/Engine/Graphics/DynamicBuffer.h

@@ -75,6 +75,27 @@ public:
         Data.Add((byte*)bytes, size);
     }
 
+    /// <summary>
+    /// Allocates bytes in the buffer by resizing the buffer for new memory and returns the pointer to the start of the allocated space.
+    /// </summary>
+    /// <param name="size">Amount of data to allocate (in bytes)</param>
+    FORCE_INLINE byte* WriteReserve(int32 size)
+    {
+        const int32 start = Data.Count();
+        Data.AddUninitialized(size);
+        return Data.Get() + start;
+    }
+    
+    /// <summary>
+    /// Allocates bytes in the buffer by resizing the buffer for new memory and returns the pointer to the start of the allocated space.
+    /// </summary>
+    /// <param name="count">Amount of items to allocate</param>
+    template<typename T>
+    FORCE_INLINE T* WriteReserve(int32 count)
+    {
+        return (T*)WriteReserve(count * sizeof(T));
+    }
+
     /// <summary>
     /// Unlock buffer and flush data with a buffer (it will be ready for an immediate draw).
     /// </summary>