Gorf colors and the long time red shade color of the apple video output of Mr. Do Two of the more memorable color output issues either mentioned on old MAME.net forums and here as well. iirc Mr. Do red color output may have been resolved a long time ago, but it was an ongoing occasional topic on the forums for a few years.
Here are some detailed video output work updates that involved couriersud's work. The work on the Williams games is interesting by itself. If the monitors used with Midway Astrocade hardware is same monitor model used with some of the Williams games, maybe a similar approach can be done? I am unsure which monitors were used with Williams games and Midway Astrocade hardware.
Use netlist to calculate RGB values for Turkey Shoot. [Couriersud] This example shows how the netlist tools can be used to derive RGB tables from a schematic. All steps are given in serc/lib/netlist/examples/turkey_shoot.cpp
williams.cpp: Improve williams2 color display. [Couriersud] Change color levels for williams2 hardware to better color display. Output levels are computed in netlist. These levels are aligned to LTspice modelling I did. Also improved the modelling to do what the actual hardware for mysticm did: Color decoding depends on W13..W11. These are actually flip screen versions of V13..V11. Fixed treatment on Bit0 although not used by the game code. Added R,G,B gain and offset sliders for the williams2 hardware. MAME only supports one setting for all channels. This is not good enough to come close to video recordings found on youtube.
Minor changes to nltool to better measure time taken to run a simulation.
Williams2: Improve color processing. [Couriersud] offsets now cut off before gain is applied. This is how the "cutoff" monitor controls on arcade monitors worked. Adjusted R,G,B gains and offsets.
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Re: Correct colors in GORF
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