add GeometryBuffer class to pass data from MapDatabase to TileGenerator

src/org/oscim/core/GeometryBuffer.java

@@ -0,0 +1,42 @@
+package org.oscim.core;
+
+public class GeometryBuffer {
+	public float[] points;
+	public short[] index;
+	public int indexPos;
+	public int pointPos;
+
+	public GeometryBuffer(float[] points, short[] index){
+		this.points = points;
+		this.index = index;
+	}
+	public GeometryBuffer(int numPoints, int numIndices) {
+		this.points = new float[numPoints * 2];
+		this.index = new short[numIndices];
+	}
+
+	public float[] ensurePointSize(int size, boolean copy){
+		if (size * 2 < points.length)
+			return points;
+
+		float[] tmp = new float[size * 2 + 1024];
+		if (copy)
+			System.arraycopy(tmp, 0, points, 0, points.length);
+
+		points = tmp;
+		return points;
+	}
+
+	public short[] ensureIndexSize(int size, boolean copy){
+		if (size < index.length)
+			return index;
+
+		short[] tmp = new short[size + 128];
+		if (copy)
+			System.arraycopy(tmp, 0, index, 0, index.length);
+
+		index = tmp;
+
+		return index;
+	}
+}