Lesson 4 - game fix

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Summary

This lesson will show one way to go about fixing the entire game, getting it playable as quickly as possible.


Level of difficulty: Easy
Time required: 25 minutes

Video Walkthrough on YouTube
Video Walkthrough direct download link

Objective

Fix the entire game, all shaders that cause 3D glitches, making it playable.
Learn how HelixMod constants work.


Quiz

Save and upload two screen shots. This time, using the on/off key mechanism to show any scene with glitches, then all of them fixed.


Even with the tiny information that we have so far, we can still fix entire games!

Let's go through The Ball and fix every broken effect that we find. After we finish disabling all the broken effects, we will have a fully playable game in 3D.

There is a trade-off between fixing effects and simply disabling them. Naturally, we'd want to fix things instead of just disabling them, but fixing things is quite a lot harder and more time-consuming than simply disabling them.

There is an artistic balance to be struck between how much an effect is worth, compared to how bad it looks in 3D. This is simply a judgment call, and everyone will have a different opinion. In general, we try to lean toward fixing everything, but if you only have a little bit of time, it's far better to have a game that runs with effects disabled, than no game at all. For this Lesson we are going to concentrate upon getting results quickly, not necessarily the best results.

As we go through this Lesson, we'll get a chance to see how that balance plays out with different effects.


Before we get started disabling effects, let's take a quick look at another HelixMod feature that we are going to use extensively it the future. Our use here will be a simple version, but a good introduction.

In the HelixMod d3dx.ini file, we can add Constants, and we can then use those constants in any Pixel or Vertex Shader. They are provided by the tool as a convenience, and for any purpose that we wish.

For our simpler example here, let's make a simple on/off mechanism, where we can decide in each shader whether to show the original shader, or our disabled version. There is no particular advantage to do this, other than it's interesting, but it can make it easier to decide whether something needs to be fixed or if disabled is good enough.

  • Create an on/off mechanism using HelixMod constants
    1. Remove dumpall for speed.
    2. Show constant use in shaders.
    3. Demo constant for on/off display use.



As a first pass, let's find and mark all the broken shaders. We'll still look for them one at a time, so we can easily keep track of what we need to do.

In a later Lesson, we'll come back to these disabled shaders in order to actually fix them. Having them all in the same spot, with good comments will make it easy for us to find effects, and decide which are worth more time to actually fix. In a very real sense, this is a working ToDo list, but without us having to write a bunch of notes.


  • Creating a complete list of shaders.
    1. Since we want quick results, we can turn effects off with UI instead of fixing or disabling them.
    2. First pass in game, finding broken shaders.
    3. Relaunch at different saves to shorten active search list.
    4. Mark every shader that needs fixing. Comment each one in the Dumps folder.



With all the broken shaders saved in the ..\Dumps\SingleShaders\ folder, we can now go through and disable each of them. We'll use our on/off mechanism so that we can decide how much of an impact disabling each effect has.

  • Editing shaders to disable effects
    1. Fix full game. All shaders gone.
    2. Most are no big loss, but what about lava?
    3. Fix lava by killing one layer instead.



That's all there is to disabling effects in a game, and hopefully you see how quickly and easily you can fix an entire game. It can be improved, but isn't it already far better than when we started?

Time for the Quiz, for you to demonstrate that you successfully disabled some effects, using the on/off constants mechanism.


  • Save and upload before and after 3D snapshots
    1. Find a good spot in the game where something was fixed.
    2. Set the fixes to off, and snapshot the broken image with Alt-F1.
    3. Set the fixes to on, and snapshot the new and improved image with Alt-F1.
    4. Upload your two snapshots, using the Special:Upload link.
    5. Navigate to your personal wiki page from the upper right.
    6. Edit your personal page, and add == Lesson 3 == and any comments you'd like.
    7. Add Before: and your before filename reference as: [[File:before filename|700px]]
    8. Add After: and your after filename reference as: [[File:after filename|700px]]
    9. Check your page with Preview to be sure you like it.
    10. When you are satisfied, click Save Page.



Did you successfully disable every annoying effect? You just fixed a complete game. Incredible!


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