The (GPv2) fill tool has an "extension" mode to assist with filling
small gaps where strokes don't fully meet.
- Overlay: Draws various helpers during modal fill tool operation, using
the same functions as the render-to-image used for applying the fill
tool.
- Extension lines: Scrolling or page up/down extends the tips of strokes
and draws extra boundary lines to limit filling.
- Extension circles: Press S to toggle the mode. This draws circles
around stroke tips.
- Stroke overlay: This can be enabled in the brush settings
(_Advanced > Visual Aids_) to draw strokes in a simple color on top of
the viewport.
- Extension line collision: Tests for intersections of extension lines
with other lines and with strokes, and cuts them short. Enable in
brush settings (_Advanced > Strokes Collision_).
- Better defaults for extension increments: The values are in Blender
units, and quite arbitrary. Using lower values makes it feel more like
GPv2 in the 2D animation template.
- Draw functions in the `ed::greasepencil::image_render` namespace now
consistently expect coordinates in view space (avoids confusion and
works better for 2D elements).
- Some internal renaming and cleanup (many variable names come from GPv2
and were not very clear).
Pull Request: https://projects.blender.org/blender/blender/pulls/122771
3d4b8f91e7