I have made a quick animation of what I think the lighting scheme could look like. Here is a sample image:
There are a few parameters that I messed around with such as the spotlight angle (20 degrees as pictured above), the shine distance (~45 or 50 as pictured), and the light dropoff rate (I'll explain more about this for anyone interested, but it's not an important detail).
I support this idea, but I think it might be a little hard to implement due to the janky and laggy way Minecraft calculates lighting. They could, of course, rework the lighting system but you might not get the result you want without a raytracer.
In addition, maybe this could be a toggle-able light source using redstone?
I used a program called Autodesk Maya to make the lamp. This is a program commonly used for 3D work in movies such as the ones from DisneyToon.
While it has an extremely efficient viewport with live lighting preview, it still struggled to keep up when I rotated the lamp which is why I have concerns regarding the performance of this ingame. If the lamp doesn't have to rotate while on, then they would only have to calculate it once and it should be OK.
How far do you think the light should shine? Should it have something like a linear, or quadratic falloff rate?
@RavbugAnimations I like Autodesk's tools, though I have used Maya probably only twice. Cool stuff!
The way I like to think of the lighting mechanics as it pertains to the spotlight is as though the spotlight is a directed torch. This way, the game can compute the lighting for the affected blocks one time, then maintain that light level until pertinent block updates are made. I think this would resolve the laggy lighting issue.
As for the lighting profile, I like to think of it (in mathematical terms) as the following:
In a continuous space, consider a direction unit vector (representative of the light orientation) about a point (representative of the light position). Consider a disk normal to this vector and centered along its axis with a radius that scales with the distance of its center to the location of the spotlight. The union of all of these disks (up to a fixed limit) defines a cone oriented somewhere in space. All blocks that are inclusively inside this cone would have light level 15, and then the light level would trail off after that (see: Spread). Obstructions are handled as they are in the case of torches.
I would suggest a fixed limit of around 40-50 blocks.
I'll try to make a visual for this here soon - I do not currently have access to most of my digital tools, but I'll figure something out!