# Line joints and caps

Every Line2D joint, cap and gradient side by side.

```{raw} html
<a class="example-run-button" href="../demos/features_2d_line_joints_and_caps.html">▶ Run in browser</a>


```

**Tags:** `2d`

A `Line2D` is more than a run of segments. Where it bends it leaves a notch,
and `joint_mode` decides what fills it; where it ends it stops flat, and
`begin_cap_mode` / `end_cap_mode` decide whether it rounds off; and `gradient`
colours it along its own length instead of flat.

## How it works

Four rows, each the same zigzag drawn with a different setting so the
difference is visible rather than described:

1. `joint_mode` is `"sharp"` (a miter), `"bevel"` (a flat corner) or `"round"`
   (an arc). A miter that would shoot a spike off a near-reversal falls back to
   a bevel on its own.
2. `begin_cap_mode` and `end_cap_mode` are `"none"` or `"round"`, and each end
   is set independently.
3. `gradient` is a list of `(t, colour)` stops. `t` runs from 0 at the first
   point to 1 at the last, measured along the line, and the gradient replaces
   `colour` rather than tinting it.
4. A `width` of 1.0 or less is a hairline: it rides the one-pixel line pipeline
   whatever the camera is doing, so it has no width for a joint or a cap to
   fill and neither is drawn.

The alpha on the top row is deliberately low: a joint fills the outside of a
bend only, so a translucent line does not darken along its own corners.

## Source

```{literalinclude} ../../examples/features/2d/line_joints_and_caps.py
:language: python
:linenos:
```