/** Add a ring to a builder */
private void addRing(LineString r, Geobuf.Data.Geometry.Builder builder) {
// skip last point, same as first
builder.addLengths(r.getNumPoints() - 1);
long x, y, prevX = 0, prevY = 0;
// last point is same as first, skip
for (int i = 0; i < r.getNumPoints() - 1; i++) {
// delta code
Coordinate coord = r.getCoordinateN(i);
// note that roundoff errors do not accumulate
x = (long) (coord.x * precisionMultiplier);
y = (long) (coord.y * precisionMultiplier);
builder.addCoords(x - prevX);
builder.addCoords(y - prevY);
prevX = x;
prevY = y;
}
}
/** Moves the iterator ahead to the next vertex and (possibly) linear component. */
public void next() {
if (!hasNext()) return;
vertexIndex++;
if (vertexIndex >= currentLine.getNumPoints()) {
componentIndex++;
loadCurrentLine();
vertexIndex = 0;
}
}
/**
* Tests whether there are any vertices left to iterator over. Specifically, hasNext() return
* <tt>true</tt> if the current state of the iterator represents a valid location on the linear
* geometry.
*
* @return <code>true</code> if there are more vertices to scan
*/
public boolean hasNext() {
if (componentIndex >= numLines) return false;
if (componentIndex == numLines - 1 && vertexIndex >= currentLine.getNumPoints()) return false;
return true;
}
/**
* Checks whether the iterator cursor is pointing to the
* endpoint of a component {@link LineString}.
*
* @return <code>true</true> if the iterator is at an endpoint
*/
public boolean isEndOfLine() {
if (componentIndex >= numLines) return false;
// LineString currentLine = (LineString) linear.getGeometryN(componentIndex);
if (vertexIndex < currentLine.getNumPoints() - 1) return false;
return true;
}