diff --git a/src/modules/graphics/opengl/SpriteBatch.cpp b/src/modules/graphics/opengl/SpriteBatch.cpp
index d7ce83a7f..c645b916b 100644
--- a/src/modules/graphics/opengl/SpriteBatch.cpp
+++ b/src/modules/graphics/opengl/SpriteBatch.cpp
@@ -69,7 +69,7 @@ namespace opengl
 		// Fill element buffer.
 		{
 			VertexBuffer::Bind bind(*element_buf);
-			VertexBuffer::Mapper mapper(*element_buf, GL_WRITE_ONLY);
+			VertexBuffer::Mapper mapper(*element_buf);
 
 			GLushort *indices = static_cast<GLushort*>(mapper.get());
 
@@ -158,7 +158,7 @@ namespace opengl
 	{
 		VertexBuffer::Bind bind(*array_buf);
 
-		return array_buf->map(GL_READ_WRITE);
+		return array_buf->map();
 	}
 
 	void SpriteBatch::unlock()
diff --git a/src/modules/graphics/opengl/VertexBuffer.cpp b/src/modules/graphics/opengl/VertexBuffer.cpp
index e1dfed529..d5f969356 100644
--- a/src/modules/graphics/opengl/VertexBuffer.cpp
+++ b/src/modules/graphics/opengl/VertexBuffer.cpp
@@ -72,7 +72,7 @@ namespace opengl
 		delete [] buf;
 	}
 
-	void *VertexArray::map(GLenum/* access*/)
+	void *VertexArray::map()
 	{
 		return buf;
 	}
@@ -122,20 +122,21 @@ namespace opengl
 			unload(false);
 	}
 
-	void *VBO::map(GLenum access)
+	void *VBO::map()
 	{
-		// Don't map twice.
+		// mapping twice could result in memory leaks
 		if (mapped)
-			return mapped;
+			throw love::Exception("VBO is already mapped!");
 
-		mapped = glMapBufferARB(getTarget(), access);
+		mapped = malloc(getSize());
 
 		return mapped;
 	}
 
 	void VBO::unmap()
 	{
-		glUnmapBufferARB(getTarget());
+		glBufferSubDataARB(getTarget(), 0, getSize(), (void*)mapped);
+		free(mapped);
 		mapped = 0;
 	}
 
@@ -209,7 +210,7 @@ namespace opengl
 			GLint size;
 			glGetBufferParameterivARB(getTarget(), GL_BUFFER_SIZE, &size);
 
-			const char *src = static_cast<char *>(map(GL_READ_ONLY));
+			const char *src = static_cast<char *>(map());
 
 			if (src)
 			{
diff --git a/src/modules/graphics/opengl/VertexBuffer.h b/src/modules/graphics/opengl/VertexBuffer.h
index a9e13c8c8..1fc1f7c74 100644
--- a/src/modules/graphics/opengl/VertexBuffer.h
+++ b/src/modules/graphics/opengl/VertexBuffer.h
@@ -104,10 +104,9 @@ namespace opengl
 		 *
 		 * The VertexBuffer must be bound to use this function.
 		 *
-		 * @param access GL_READ_ONLY, GL_WRITE_ONLY, GL_READ_WRITE.
 		 * @return A pointer to memory which represents the buffer.
 		 */
-		virtual void *map(GLenum access) = 0;
+		virtual void *map() = 0;
 
 		/**
 		 * Unmap a previously mapped VertexBuffer. The buffer must be unmapped
@@ -182,9 +181,9 @@ namespace opengl
 			/**
 			 * Memory-maps a VertexBuffer.
 			 */
-			Mapper(VertexBuffer& buffer, GLenum access)
+			Mapper(VertexBuffer& buffer)
 				: buf(buffer)
-			{ elems = buf.map(access); }
+			{ elems = buf.map(); }
 
 			/**
 			 * unmaps the buffer
@@ -236,7 +235,7 @@ namespace opengl
 		virtual ~VertexArray();
 
 		// Implements VertexBuffer.
-		virtual void *map(GLenum access);
+		virtual void *map();
 		virtual void unmap();
 		virtual void bind();
 		virtual void unbind();
@@ -270,7 +269,7 @@ namespace opengl
 		virtual ~VBO();
 
 		// Implements VertexBuffer.
-		virtual void *map(GLenum access);
+		virtual void *map();
 		virtual void unmap();
 		virtual void bind();
 		virtual void unbind();
@@ -307,6 +306,10 @@ namespace opengl
 		// A pointer to mapped memory. Zero if memory is currently
 		// not mapped.
 		void *mapped;
+
+		// Usage hint for map()/unmap() pair. Same as `access' parameter in
+		// glBufferData or 0 if not mapped.
+		GLenum mapped_access;
 	};
 
 } // opengl