Patch compatibility: Power Mode 2003

[florianessl]

This PR adds compatibility for the PowerMode 2003 patch.
Other than the missing support for AAC audio files & the mapping of mouse buttons, this patch implementation should be feature-complete. (and less buggy than the original patch)

Depends on PR #3378 because I didn't want to create a new file for this implementation alone.

I did some research on this obscure patch & documented my findings in more detail on Makerpendium:
https://www.makerpendium.de/index.php?title=PowerMode_2003

There's an article on Hellsoft about this patch, that also includes a small sample project:
https://www.hellsoft.net/H5/reportajes/95-reportajes-especiales/150-power-mode-2003

Implemented features

• Control Register 0
  • Opening Load Menu by setting V01:CR0 to 255
  • Exiting the game by setting V01:CR0 to 254
  • Retrieving value of V01:CR0 to check if Savefiles exist (Result = 1)
• Mouse Cursor Support
  • Writing current cursor X/Y to V02:MCOORDX & V03:MCOORDY whenever a value is written to V03:MCOORDY
• Full Keyboard Support using VirtualKey-IDs
  • Mode 0 will check entire Keyboard for presses and store pressed key with lowest priority to V04:KEY
  • Mode 1 to 255 will check a single Keycode and store its ID to V04:KEY (Otherwise 0)
• Floating point operations using V05:FVALUE1 / V06:FVALUE2 / V07:FCODE
  • Mode 1: Calculation of sin / cos
  • Mode 2: Calculation of tan
  • Mode 3: Calculation of sqrt, with natural & fractional parts of result stored separately
  • Mode 4: Calculation of flaot division, with natural & fractional parts of result stored separately
• "Special Mode" (Custom picture rotations)
  • Overriding the default rotation effect & rotating Pic-IDs 1-50 by a user-defined amount
    (Start of variable range stored in V08:SPECIAL - Block of 50 variables containing set rotation degrees from 0 - 256)
• Other / Behavior changes when patch is applied:
  • Detection of patch by checking existence of file warp.dll
  • Skipping the title screen by automatically setting "new-game" = 1
  • Support for AAC files (Not implemented - should be part of another PR)
  • Replacing the default behavior for picture setting 'bottom transparency'
    (Standard picture rotation effect will be applied counter-clockwise if this value is abova 49)
  • Mapping Mouse buttons LEFT / RIGHT to in-game buttons DECISION / CANCEL

[ghost]

Besides -Wunused warnings, looks good to me!

[ghost]

Mapping Mouse buttons LEFT / RIGHT to in-game buttons DECISION / CANCEL (Not implemented)

Related: #634

[florianessl]

Button mapping for Mouse L/R is now also implemented.

This fixes a screen for this Spanish zelda fangame: https://www.hellsoft.net/H5/component/remository/Juegos/Rpg-Maker-2003/The-Legend-of-Zelda-Necklace-of-Elements/?Itemid=537

[carstene1ns]

This needs to be documented (manual, help message)

[florianessl]

There's already a line for this patch option in the help message.
I don't have any idea about the state of the online manual - probably way out of date.

[Ghabry]

yeah the manual (manpage) is usually a bit behind because we forget updating it. I usually copy everything over before the next release xD.
Thanks for the PR. Will review it next week.