Occasional gaps in lines

[olavolav]

Sometimes there are gaps at the end of lines.

To reproduce

>>> from uniplot import plot
>>> plot(xs=[0.433,0.6666], ys=[0.8,0.1133], x_min=0, x_max=1, y_min=0, y_max=1, lines=True)
DEBUG indices_slope -0.8571428571428571 slope -2.939640410958905
DEBUG x_index_start 51
DEBUG x_index_stop 79
DEBUG x_indices_of_line [52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75
 76 77 78]
┌────────────────────────────────────────────────────────────┐
││                                                           │ 1.0
││                                                           │ 
││                                                           │ 
││                        ▝▖                                 │ 
││                         ▝▚                                │ 0.7
││                           ▚                               │ 
││                            ▚▖                             │ 
││                             ▝▖                            │ 
││                              ▝▖                           │ 0.5
││                               ▝▚                          │ 
││                                 ▚                         │ 
││                                  ▚▖                       │ 
││                                   ▝▖                      │ 0.3
││                                    ▝▖                     │ 
││                                     ▝▘                    │ 
││                                      ▝                    │ 
││▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁│ 0.0
└────────────────────────────────────────────────────────────┘
 0                                                          1

This is not a bug, but an artifact of the line drawing attempting to be accurate. If the end pixel is drawn because of an end pint that is significantly away from the center of the pixel then this is possible.

Possible solutions

• The obvious solution would be to draw the line between the middle points of the start and end pixel, not the actual line.
• An alternative might be to check for gaps and correct it by drawing another pixel.

[olavolav]

Let's go with the first solution for the moment. The result looks like this:

>>> from uniplot import plot
>>> plot(xs=[0.433,0.6666], ys=[0.8,0.1133], x_min=0, x_max=1, y_min=0, y_max=1, lines=True)
┌────────────────────────────────────────────────────────────┐
││                                                           │ 1.0
││                                                           │ 
││                                                           │ 
││                        ▝▖                                 │ 
││                         ▝▚                                │ 0.7
││                           ▚                               │ 
││                            ▚▖                             │ 
││                             ▝▖                            │ 
││                              ▝▖                           │ 0.5
││                               ▝▚                          │ 
││                                 ▚                         │ 
││                                  ▚▖                       │ 
││                                   ▝▖                      │ 0.3
││                                    ▝▖                     │ 
││                                     ▝▚                    │ 
││                                      ▝                    │ 
││▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁│ 0.0
└────────────────────────────────────────────────────────────┘
 0                                                          1

[olavolav]

Actually, the fix that is implemented now does the above but will also reject "overshoot". So it's even a mix between the above solutions.