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Doctor Who (Bally 1992)

A quick VPW Mod build for Bally's 1992 Doctor Who, notable for establishing the insert bloom sizing standard ("1/3 the size that feels natural"), documenting frame pacing vs FPS, and the GI ball reflection technique using elevated lights. Collaborative build between sixtoe, rothbauerw, apophis79, and lumigado.

Build Story

A relatively quick Lite/Mod build rather than a full Premium table. The project focused on physics integration, insert lighting upgrades, and desktop backdrop enhancements rather than a full Blender toolkit rebuild.

Table-Specific Details

Mechanisms & Hardware

Dr. Who uses lightning flippers at 2.875" (not the standard 3"). VP unit conversion: 2.875" = 135 VP units vs 141 for standard flippers. The shorter flippers create a wider gap between tips, making the game noticeably more difficult. Always check the machine manual for exact flipper bat part numbers rather than assuming standard dimensions.

Art & Visuals

  • Environment image caused asymmetric lighting -- a bright white bloom in the center made the left side washed out relative to the right. Replaced with Flupper's shinyenvironment image which has more even distribution without visible hotspot reflections.
  • Desktop backdrop with Doctor indicators around the DMD implemented using VPX light objects (not flashers -- flashers cannot be used on the backdrop) driven by Lampz via MassAssign with corresponding ROM lamp numbers. Light intensity around 2.5 works well for backdrop indicators. Backdrop lights made conditional on DesktopMode to prevent showing in cabinet mode.
  • DMD textbox aspect ratio should be set to approximately 300x90 to respect the display's native ratio -- the default DMD size is squished vertically.

Desktop DMD Visibility

The UseVPMColoredDMD constant controls desktop DMD visibility. For cabinet mode, the initial declaration must be False. A common release-day bug: forgetting to set the initial const to False causes the DMD to render in both desktop and cabinet modes.

Known Issues

  • Primitives with transparency settings caused light bleed-through in VR that was invisible in desktop mode. Fix: adjust material transparency amount in the VPX material editor.

Techniques Developed Here

  • Insert bloom sizing standard -- approximately 1/3 the size that feels natural when first placing them, tested on cabinet and VR setups
  • GI ball reflection technique -- VPX lights at Z=52 height around slingshots and high-traffic areas create visible GI reflections on the ball as it passes through ("Skitso-style")
  • Frame pacing vs FPS -- stable frame pacing matters more than raw FPS; 144 Hz vs 240 Hz indistinguishable
  • Alpha mask workflow for insert cutouts documented as "hours-long" but the mask-based approach is more forgiving than direct pixel deletion

See Also