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coding-horror / basic-computer-games

An updated version of the classic "Basic Computer Games" book, with well-written examples in a variety of common MEMORY SAFE, SCRIPTING programming languages. See https://coding-horror.github.io/basic-computer-games/
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Lunar lander initial weight #867

Open martincmartin opened 1 year ago

martincmartin commented 1 year ago

There was a change recently, by @sergev, to the initial weight of the Lunar Lander. It looks like it was changed to be faithful to the original Lunar Landing game from 1969 by Jim Storer in FOCAL.

However, BASIC Computer Games seems to have intentionally given the user extra fuel. The intro text says "To make the landing more of a challenge, but more closely approximate the real Apollo LEM capsule, you should make the available fuel at the start (N) equal to 16,000 lbs, and the weight of the capsule (M) equal to 32,500 lbs."

Note the N is not the available fuel at start, but the empty weight of the capsule. The available fuel is M - N.

In the original 1969 FOCAL code,

M=32500 N=16500 M-N = 16000

In BASIC Computer Games, we have:

M=33000 N=16500 N - M = 16500

So it looks like it was modified intentionally, to make things a little easier for the player.

If we want to go with the original values from 1969, we should remove the (erroneous) message from the intro.

If we want to stick with the BASIC Computer Games version of extra fuel, we should probably fix the intro text, or at least mention the bug that you only need to update M, since N is actually the empty weight.

coding-horror commented 1 year ago

Sure! Good idea. Maybe put that in the root porting notes for that program?