#17 First Lighting
This week I took the 3D scan from last week, added it to a new Unreal project, and took a first pass at lighting it in the engine. While I’ve got a whole list of minor issues and problems to look into and fix, overall this has been fairly intuitive and a ton of fun to play around with.
I did have to convert my model to a .fbx to get it into Unreal. I’d downloaded an .obj file from the Kiri app since it’s one of the format options that I’m the most familiar with, but found that I wasn’t able to import that type of file into Unreal. I used Blender to convert it to a .fbx, which worked fine. I suppose in the future I should just download a .fbx to begin with.
Once it was in unreal, positioning and lighting the model was both intuitive and fun. Unreal has a handful of options for lighting sources, including the sun, omnidirectional light sources, spotlights, 2D lights, and directional light.
The Sun: Dropping the model in, adjusting the “solar time,” and lining up the model was the gateway drug of lighting in Unreal. It’s easy and beautiful and I can’t wait to see what it looks like on the wall in real life.
Omnidirectional light sources are fun to play with, and are easy to pick either a color or set a specific “white” by color temperature.
Spotlights are directional, and in addition to all the settings of an omnidirectional light, you can set a beam and field angle, and I’ve found these to be the most fun to play with. They’re great as sources for the wall sconces, as well as off to the side, and have the advantage (over their real-life counterparts) of having, essentially, infinite brightness.
2D lights are a rod of omnidirectional light in a set length, and fit great as a strip light below each window. It would be great if they could be directional too, but at the moment that doesn’t seem to be an issue.
Directional Light is confusing. It definitely washes the set in light, but I haven’t quite figured out where it comes from or how to control it.
In addition to the lights, I also used the existing camera to try lining up some projection angles. These cameras have a ton of features, letting you set basic stuff like FOV, but also a ton of details that would mean a lot to me if I did more cinematography. There are two cameras in this – one is inside the .fbx, and whenever I use that one there’s an orange “highlight” around the edges of and sometimes in the middle of the mesh that I don’t want in a projected image. Fortunately, there’s also a camera that’s not in the .fbx file and that one doesn’t include these orange lines.
I made a collection of first looks to experiment with these sources and the engine, ran into a ton of fun issues, and have a long list of questions to ask and things to do differently on a second pass at this.
Issues:
Model has floating blobs and other details (this currently causes unrealistic shadows in sunlight, and will definitely be a problem when 3D printing a scale model)
The model is just a shell, w/out any depth, and so isn’t printable at the moment and I’ll have to learn a bit of 3D modeling (probably in Blender) if I want to make that happen.
I wasn’t able to import an .obj file. This wasn’t a big issue, but is kind of surprising and I’m curious if I’m doing something wrong.
Object was not perfectly lined up with an axis when I started, which meant that duplicating sources along the wall took a bit of finesse (whereas, if the object were perfectly aligned with one axis, I would be able to single-click-and-drag to duplicate light sources along the wall)
Sunlight shines through the backside of the model. I’m sure there’s an easy fix for this, although making it a 3d-printable model likely be one.
