This had two different flags that were checked totally inconsistently, and one was not even saved.
Moved everything into a few subfunctions so that these checks do not have to be scattered all over the code.
Many uses of random() & value have been turned into random(0, value).
This is not only more efficient, it also ensures better random distribution because the parameter-less variant only returns values between 0 and 255.
There was a clear attempt here to let the item keep control of the remaining morph time, but since the item would have gotten destroyed right afterward it just shot itself in the foot badly by doing so.
Just leaving the remaining work to the main unmorphing check in the PlayerThink code by doing nothing will avoid the bad situation where a player gets stuck in its morphed form.
- replaced Inventory.DrawPowerup with a GetPowerupIcon method so that the calling code can handle the drawing and apply its own rules. This was a major design flaw of allowing the inventory items to handle the drawing themselves, because they were unable to adjust to different HUD frontends. Note that any mod that overrides DrawPowerup will not draw any icon that expects to be handled that way!
- the alternative HUD now has its own, separate drawer that obeys the AltHUD's rules, and not the ones of the normal fullscreen HUD.
- the standard drawer has been scriptified as a virtual function.
- Both drawers now handle positioning of the icon inside its assigned box themselves instead of trusting the powerup item to do it correctly.
- DTA_HUDRules and Screen.DrawHUDTexture are to be considered deprecated because both do not integrate into the redesigned HUD code.
Clearscope is a dangerous context and should be limited to the minimum extent possible and preferably be blocked in user code.
This may still need some work on const functions but better have it in now.
- handle these powerups by actual item checks instead of cheat flags. (The same should also be done for the Frightener and Buddha but those are a bit more complex because they are also real cheats.)
- ensure that actor defaults contain a valid virtual table and class pointer so that they can actually use virtual and class-dependent method functions. This is needed for retrieving script variables from them.
- added some helpers to set scripted member variables through the native property parser.
Unfortunately some classes, e.g. PowerMorph, MorphProjectile and the powerup contain some that cannot be handled through the 'property' definition on the script side so they need to be done from the native side.
This revealed an interesting bug: When the berserk fadout formula was changed in 2005 the result was essentially broken, resulting in values around 7000 - it only worked by happenstance because the lower 8 bits of the resulting values just happened to work to some degree and never overflowed. But the resulting fade was far too weak and a slightly different handling of the color composition code for the VM made it break down entirely.
This restores the pre-2005 formula but weakened intensity which now comes a lot closer to how it is supposed to look.
