checkpoint: thinking out loud

Author: philiplinden

Cargo.lock

@@ -1,6 +1,6 @@
 [package]
 name = "spacetime"
-version = "0.2.0"
+version = "0.2.2"
 authors = ["Philip Linden <lindenphilipj@gmail.com>"]
 edition = "2021"
 
@@ -34,13 +34,12 @@ avian2d = { version = "0.1.1", features = [
     "serialize",
 ] }
 bevy_lit = "0.3.0"
-bevy-inspector-egui = { version = "0.25.1", features = ["highlight_changes"] }
 bevy_pancam = { version = "0.14.0", features = ["bevy_egui"] }
 serde = { version = "1.0.209", features = ["derive"] }
 nyx-space = "1.1.2"
 
 [dev-dependencies]
-bevy-inspector-egui = { version = "0.25.1", features = ["highlight_changes"] }
+bevy-inspector-egui = { version = "0.26.0", features = ["highlight_changes"] }
 bevy_mod_debugdump = "0.11.0"
 
 [features]

Cargo.toml

@@ -1,8 +1,20 @@
-# 2D, not 3D
+# 2D or 3D?
 
-In 2D physics-space, rendering-space, and screen-space are basically the same thing. We can hand-wave away translations
-therein and all the complexities of visualizing information about a 3D volume in 2D screen-space. 
+In 2D physics-space, rendering-space, and screen-space are basically the same
+thing. We can hand-wave away translations therein and all the complexities of
+visualizing information about a 3D volume in 2D screen-space. 
 
-2D simulation space was selected mainly because it simplifies visualizations of information like gravitational potential
-over large areas and it makes the use of compute shaders simpler as well. For example, offloading those gravity field
-calculations to the GPU with a shader and then recovering that information back on the CPU later.
+2D simplifies visualizations of information like gravitational potential over
+large areas and it makes the use of compute shaders simpler as well. For
+example, offloading those gravity field calculations to the GPU with a shader
+and then recovering that information back on the CPU later.
+
+We can skip the complexities of general physics by using Nyx and other vetted
+libraries. These libraries take complicated 3D interactions, NASA almanacs, and
+other intracies into account under the hood. Nyx gives us the 3D engine "for
+free" so to speak, so we can focus on the time dilation aspect of relativity
+without having to worry about the complexities of general physics. However, we
+are limited by the number of bodies we can simulate. 
+
+The benefit of 2D physics is that it's easier to simulate. The benefit of 3D
+physics is that it's more realistic.

docs/design/simulation_limits.md

@@ -113,3 +113,13 @@ anymore. Honestly this might also rule out the necessity for Avian as well.
 Since Nyx is a real astrodynamics crate, I'm basically locked into 3D as well.
 
 I put settings, constants, etc. in another RON file for safe keeping.
+
+# 2024-09-16
+This video
+[series](https://www.youtube.com/playlist?list=PLu7cY2CPiRjVY-VaUZ69bXHZr5QslKbzo)
+on relativity is very helpful. I'm going to watch it through a few times and try
+to implement some of the examples in code.
+
+I also read [some additional research](docs/research-papers/Meyers_1999_LunarTime.pdf)
+on defining a lunar time scale and it looks simple enough to implement. Famous
+last words.

docs/devlog/v0.2.2.md

@@ -1,3 +1,4 @@
+# these packages are required to build the docs site
 jupyter>=1.0.0
 mkdocs>=1.5.3
 mkdocs-material>=9.4.8