updateForCamera method
Rebuilds the camera-facing strip for camera and viewportSize.
Call once per frame before rendering. Reuses the GPU buffers.
Implementation
void updateForCamera(Camera camera, ui.Size viewportSize) {
final expanded = expandPolyline(
_points,
widths: _widths,
widthMode: _widthMode,
diskPoints: _diskPoints,
drawStart: drawStart,
drawEnd: drawEnd,
viewProjection: camera.getViewTransform(viewportSize),
cameraPosition: camera.position,
viewportSize: viewportSize,
);
updatePositions(expanded.positions);
updateNormals(expanded.normals);
}