Workbench: Add back studio lighting presets

This changes a bit how the userprefs solid lights works. They are not
visible until enabling the "Edit Solid Light" checkbox. Once enabled the
current studiolight used for solid mode will be overwritten.

Once the lighting settings are tweaked, the user can click the
"Save as Studio light" button to save the current settings.
This makes it easy to create new lighting without messing the other
presets.

The studio lights are stored as ASCII files on the disk using a dead
simple custom format.

The UI/UX is not perfect and will be improved in other commits.

Also includes:
* Separate LookDev HDRI selection from Solid Lights
* Hide LookDev HDRIs from the Solid Lights selection list

1 files changed, 2 insertions, 1 deletions

diff --git a/source/blender/makesdna/DNA_userdef_types.h b/source/blender/makesdna/DNA_userdef_types.h
index 5bb3523a458..e0bed7216e2 100644
--- a/source/blender/makesdna/DNA_userdef_types.h
+++ b/source/blender/makesdna/DNA_userdef_types.h
@@ -589,7 +589,8 @@ typedef struct UserDef {
 	struct SolidLight light[3];
 	float light_ambient[3], pad7;
 	short gizmo_flag, gizmo_size;
-	short pad6[3];
+	short edit_solid_light;
+	short pad6[2];
 	short textimeout, texcollectrate;
 	short dragthreshold;
 	int memcachelimit;