5427775fef
This patch adds two theme entries for data before/after the current frame. Those entries control what color to use when displaying reference data from a different point in time (motion path, onion skins). They are under the `3D Viewport` section of the theme in the user preferences. ## User Facing Changes ### Grease Pencil When `Custom Colors` is disabled it will now use the theme instead of the layer default color. Currently this setting is enabled by default. Disable it to get Blender to use the theme. ### Motion Path If Custom Color is disabled, read from the Theme. ### Annotations If onion skin is enabled, and custom onion skin colors is disabled, read from the theme. **Grease Pencil** * previously the color used for onion skinning (without custom colors) was `U.gpencil_new_layer_col`. This is used in other places as well so it cannot be removed with this PR * By default, custom colors are enabled with Grease Pencil objects. I specifically did **not** change that with this PR. I will instead let the GP module handle that on their terms. This PR has been discussed in the Grease Pencil module meeting https://devtalk.blender.org/t/2024-05-21-grease-pencil-module-meeting/34755#meeting-notes-2 and in the A&R module meeting https://devtalk.blender.org/t/2024-05-24-animation-rigging-module-meeting/34813#patches-review-decision-time-4 Pull Request: https://projects.blender.org/blender/blender/pulls/120558