Fix (unreported) bad handling of brush's fill threshold value.

'1' threshold value would only allow to access a third of the basic
'color space' (from black to white, from 0.0 to 1.0 component values),
when you expect it to access the whole range.

Unfortunately, this needs a subversion bump to allow already defined
brushes to keep exact same behavior!

Also, did not change default value (0.2) for new brushes, think here
keeping current one makes more sense.

Thanks to @LucaRood for confirming the issue.

1 files changed, 7 insertions, 0 deletions

diff --git a/source/blender/blenloader/intern/versioning_270.c b/source/blender/blenloader/intern/versioning_270.c
index 8133d0496fa..25d78b73d59 100644
--- a/source/blender/blenloader/intern/versioning_270.c
+++ b/source/blender/blenloader/intern/versioning_270.c
@@ -1466,4 +1466,11 @@ void blo_do_versions_270(FileData *fd, Library *UNUSED(lib), Main *main)
 			}
 		}
 	}
+
+	if (!MAIN_VERSION_ATLEAST(main, 278, 4)) {
+		const float sqrt_3 = (float)M_SQRT3;
+		for (Brush *br = main->brush.first; br; br = br->id.next) {
+			br->fill_threshold /= sqrt_3;
+		}
+	}
 }