Submission #5729: DrD2k9, c-square & Radiant's DOS Space Quest: Chapter I - The Sarien Encounter in 00:52.04

Space Quest: Chapter 1 - The Sarien Encounter

Introduction/Story

• Escape the Arcada, as the self-destruct mechanism has been activated.
• Find out where the Sariens have gone.
• Find a way to prevent the Sariens from destroying his home planet.

Game objectives

• Aims for fastest time.
• Speed/Entertainment trade-offs: The speed eliminates nearly all opportunity to read the humorous text that would theoretically add entertainment value.

Challenges and Opportunities

Major 'Luck' manipulation--RNG was manipulated in multiple ways.

• The random seed is changed only when the random function is called, so the sequence of random seeds is calculable.
• Certain commands in the game advance the random seed by calling the random function to yield a random response from the game. One of these commands is simply typing 'y' and hitting enter to advance the RNG seed one step in its sequence. This was used frequently to obtain an ideal seed value for a desired outcome.
• A spreadsheet for the sequence of random seed values was developed based on the randomization formula. Though, this was initially created to aid in optimizing the slot machine sequence, we also realized that it could be used to predict and manipulate other aspects of RNG from Sarien guards, the rocks in the skimmer sequence, to even the drips of acid in the Kerona underground. Utilizing this RNG-seed spreadsheet we determined a value for the initial random seed that would yield no guards patrolling on the Arcada as well as opportunity to manipulate the longest delay for the arrival of the Spider droid on Kerona.
  • However, we were initially unsure how exactly to obtain this value for our initial random seed. We knew the value was tied to how many milliseconds after midnight the initial seed was set, but we did not know the exact mathematical formula for how it was calculated. Through a combination of brute force testing and mathematical calculations, we were able to craft a second spreadsheet which gave us the initial seed value based on the initial RTC time setting. We then started the run with this RTC value set at assembly in the emulator.
• Specific RNG manipulations (and some non-manipulations)
  • As mentioned above, the initial RTC time in JPC-rr was set to yield no Sarien guards showing up on the Arcada.
  • The initial RTC was also selected to yield an opportune random seed value for maximizing the delay of the arrival of the Sarien Spider Droid on Kerona; only one 'y' command was needed to advance the seed value to yield the longest delay.
  • A 'y' command is used to avoid acid drops in the Kerona underground.
  • Though possible, we did not use RNG manipulation to manipulate the rock placements during the Sand-Skimmer sequence. c-square developed an lua script that attempted to avoid/control rocks during the sequence, but it was not utilized in the final TAS, as the sequence itself is a timed event. Manipulating RNG would not have saved time, but may have made the movements easier.
  • We got lucky on the RNG for whether or not the skimmer is stolen in Ulence Flats and didn't require manipulation to not have it stolen.
  • We used a handful of 'y' commands to minimize the time before the alien at the slot machine gets vaporized. As can be seen, he is eliminated before we can even reach the slot machine in the bar.
  • Using the RNG sequence spreadsheet and about a dozen 'y' commands, we destroy the slot machine in a matter of seconds by controlling the RNG for the spins and maximizing payouts.
  • 'y' commands are used a couple times on the Deltaur after obtaining the Pulse Ray to manipulate the appearance of guards instead of the killer droid. Further manipulation could be utilized to eliminate guard encounters, but would take more time than just shooting the guards.

Area Specific Comments

• Slots (Major RNG dependency)
  • This was the most difficult and time consuming part of making this TAS.
  • Spins call the random function a different number times depending on whether or not the spin is a winning or losing spin. A randomized value determines whether or not a specific win result occurs, or whether a random sequence of symbols appears.
  • This submission's slot-machine sequence is GREATLY reduced compared to DrD2k9's first submission. This improvement is due to a better understanding and control of RNG.
• After obtaining the necessary funds to buy a ship (and a droid to pilot the ship), We do so and leave Ulence Flats.

• Star Generator Keypad
  • At 'Fastest' game speed, the cursor moves too fast to click the appropriate numbers, thus the speed is reduced to just 'Fast' for the numerical inputs, then returned to 'Fastest' to quickly access the 'Enter' button.
  • There are at least two layers of timing in this game. One for internal clock times (Star Generator self-destruct countdown, Arcada Self-Destruct countdown), and another for movement speeds. Unfortunately if the game in left in 'Fastest' mode after inputting the destruction code, the Deltaur will explode before the game leaves the keypad screen (itself a set timed delay after inputting the destruct code.). Therefore, we again slow the game speed to 'Fast' so that we can regain control of Roger and get him off the ship before it blows.
  • This is the single longest individual portion of the game. If the sound were left on, a VERY annoying alarm/beep goes continually throughout this wait. As such, we use an 'F2' input to turn the sound off just prior to the wait and another 'F2' input to turn it back on just following this wait.
• After initiating the self-destruct on the Star Generator, Roger escapes the Deltaur and (somehow) returns home.

Potential Improvements

• The most likely improvement possibility are based on better RNG manipulation; though the total time saved would likely be fairly minimal.
  • Actually manipulating the RNG during the skimmer sequence to yield a better string of random seed values for the slot machines could save time.
  • Determining a different starting RTC time for JPC-rr that yielded a string of random seeds that required less manipulation to begin with would also save time.
• The wait during the Detonator Keypad screen is preset in the game code. If someone were able to find a way to alter this in-game, quite a bit of time could be saved.
• Moving at the 'Fastest' pace used in this run is extremely difficult to end up where you want to go. There may be better movement patterns which we have not found.

Other Comments

• As this game foregoes multiple point gathering opportunities, it's definitely not a 100% run and one of those could theoretically be done as well.

Suggested Screenshot\

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