qumas.MicrolensingMaps.micro_maps_tracks_func module

bresenham_line(r0, c0, r1, c1)[source]

Classic Bresenham line between (r0, c0) and (r1, c1), inclusive. Returns arrays rr, cc of same length.

Parameters:

  • r0 (int)

  • c0 (int)

  • r1 (int)

  • c1 (int)

Return type:

Tuple[ndarray, ndarray]

generate_random_tracks(shape, lengths, *, n_tracks=None, seed=None, max_attempts=5000, extent=None, avoid_overlap=False)[source]

Generate straight tracks (Bresenham lines) with exact pixel lengths.

Angles are no longer biased: endpoints are sampled uniformly on the Chebyshev perimeter { (dr,dc): max(|dr|,|dc|)=L-1 }, which admits all lattice directions including true 45° diagonals and guarantees a Bresenham path of length L (unless border clipping occurs, in which case we retry).

Parameters:

  • shape ((H, W))

  • lengths (list[int] or int) – If int, you must also pass n_tracks (all tracks same length). If list, its length is the number of tracks and each entry is the pixel length.

  • n_tracks (int | None) – Number of tracks if lengths is an int.

  • seed (int | None) – RNG seed.

  • max_attempts (int) – Max attempts per track to find a valid line of exact length.

  • extent ((xmin, xmax, ymin, ymax) | None) – If provided, data coords (p0, p1) and data-space angle will be included.

  • avoid_overlap (bool) – If True, tries to avoid reusing pixels used by previous tracks.

Returns:

tracks –

Each dict has:

  • ’pix0’: (r0, c0)

  • ’pix1’: (r1, c1)

  • ’rr’: array of row indices (Bresenham path)

  • ’cc’: array of col indices (Bresenham path)

  • ’length’: int (number of pixels)

  • ’angle_deg’: float (pixel-space, y-down convention, [0,360))

  • ’p0’: (x0, y0) [only if extent provided]

  • ’p1’: (x1, y1) [only if extent provided]

  • ’angle_deg_data’: float [only if extent provided]

  • ’coords’: ((r0,c0),(r1,c1))

  • ’coords_pix’: (rr,cc)

Return type:

list of dict