diff --git a/include/pdal/PointBuffer.hpp b/include/pdal/PointBuffer.hpp
index a12fbe2be9..4beda80410 100644
--- a/include/pdal/PointBuffer.hpp
+++ b/include/pdal/PointBuffer.hpp
@@ -107,6 +107,12 @@ class PDAL_DLL PointBuffer
         m_size += buf.size();
         clearTemps();
     }
+    point_count_t append()
+    {
+        const PointId rawId(m_context.rawPtBuf()->addPoint());
+        m_index.push_back(rawId);
+        return m_size++;
+    }
 
     /// Return a new point buffer with the same point context as this
     /// point buffer.
@@ -205,6 +211,8 @@ class PDAL_DLL PointBuffer
         { return m_context.dimSize(id); }
     DimTypeList dimTypes() const
         { return m_context.dimTypes(); }
+    PointContextRef context() const
+        { return m_context; }
 
 
     /// Fill a buffer with point data specified by the dimension list.
@@ -488,7 +496,7 @@ bool PointBuffer::convertAndSet(Dimension::Id::Enum dim, PointId idx, T_IN in)
 //      block seemed somewhat expensive.
 //   2) Round to nearest instead of truncation without rounding before
 //      invoking the converter.
-// 
+//
     using namespace boost;
     static bool ok;
 
diff --git a/include/pdal/PointContext.hpp b/include/pdal/PointContext.hpp
index 548dd99e05..99b43af92b 100644
--- a/include/pdal/PointContext.hpp
+++ b/include/pdal/PointContext.hpp
@@ -76,10 +76,15 @@ class PointContext
     RawPtBufPtr m_ptBuf;
     // Metadata storage;
     MetadataPtr m_metadata;
+    // Combined size of all registered dimensions (in bytes).
+    std::size_t m_pointSize;
 
 public:
-    PointContext() : m_dims(new DimInfo()), m_ptBuf(new RawPtBuf()),
-        m_metadata(new Metadata)
+    PointContext()
+        : m_dims(new DimInfo())
+        , m_ptBuf(new RawPtBuf())
+        , m_metadata(new Metadata)
+        , m_pointSize(0)
     {}
 
     RawPtBuf *rawPtBuf() const
@@ -216,10 +221,7 @@ class PointContext
 
     size_t pointSize() const
     {
-        size_t size(0);
-        for (const auto& d : m_dims->m_detail)
-            size += d.size();
-        return size;
+        return m_pointSize;
     }
 
 private:
@@ -248,7 +250,8 @@ class PointContext
             m_dims->m_detail[*ui].m_offset = offset;
             offset += (int)m_dims->m_detail[*ui].size();
         }
-        m_ptBuf->setPointSize((size_t)offset);
+        m_pointSize = static_cast<std::size_t>(offset);
+        m_ptBuf->setPointSize(m_pointSize);
     }
 
     Dimension::Type::Enum resolveType(Dimension::Type::Enum t1,
diff --git a/include/pdal/RawPtBuf.hpp b/include/pdal/RawPtBuf.hpp
index fc32b18da7..f9b3ed5268 100644
--- a/include/pdal/RawPtBuf.hpp
+++ b/include/pdal/RawPtBuf.hpp
@@ -79,6 +79,20 @@ class RawPtBuf
         memcpy(value, buf + offset, d->size());
     }
 
+    void setPoint(PointId idx, const void *value)
+    {
+        char *buf = m_blocks[idx / m_blockPtCnt];
+        std::size_t offset = pointsToBytes(idx % m_blockPtCnt);
+        memcpy(buf + offset, value, m_pointSize);
+    }
+
+    void getPoint(PointId idx, void* value)
+    {
+        char *buf = m_blocks[idx / m_blockPtCnt];
+        std::size_t offset = pointsToBytes(idx % m_blockPtCnt);
+        memcpy(value, buf + offset, m_pointSize);
+    }
+
     void setPointSize(size_t size)
     {
         if (m_numPts != 0)
@@ -98,7 +112,7 @@ class RawPtBuf
 
     // The number of points in each memory block.
     static const point_count_t m_blockPtCnt = 65536;
-    
+
     std::size_t pointsToBytes(point_count_t numPts)
         { return m_pointSize * numPts; }
 };