[Pekka] set himself up with rather the difficulty – utilize an oscilloscope screen to screen Quake in realtime – might it even be done? Old analog range screens are just monochromatic CRTs however they are developed to draw waveforms, not render graphics.
Over the years Hackaday has tracked the development of scope-as-display hacks: Pong, Tetris, vector screen as well as pre-rendered videos. nothing that pushed limits rather like this.
[Pekka]’s service starts off the exact same as numerous others, put the range in X-Y mode as well as splice up your headphone cable television – easy. He then had to figure out some method to produce an audio signal that corresponded to the wish image. The well-known “Youscope” example demos this, however that demo is pre-rendered. [Pekka] wished to play Quake in realtime on the range itself, not just view a recording.
With only so much bandwidth offered utilizing a soundcard, [Pekka] figured he might draw a maximum of about a thousand lines on screen at a time. The very first headache was that all of his audio cards had low-pass filters on them. No method around it, he changed his ceiling accordingly. ASIO as well as PortAudio were his tools of option to produce the audio on the fly from a queue of XY lines given.
To tell his audio engine what lines to draw, he solicited Darkplaces – an open source Quake rendering engine – as well as had it strip polygons down to the bare minimum. then he had to whip out the digital hedge trimmers as well as continue pruning. This writeup truly cannot do justice to all the ingenious techniques utilized to shove the most helpful data possible with a headphone jack. If this type of thing interests you at all, do yourself a favor as well as inspect out his well-illustrated job log.
In the end [Pekka] was not completely pleased with the results. The result is playable, however only just barely. The laptop struggles to keep it easy enough, the soundcard struggles to add sufficient detail as well as the range struggles to screen everything rapidly enough. At the extremely least it sets the bar extraordinarily high for anybody wanting to one-up him utilizing this method. There is only so much water that can be squeezed from a rock.
See the video below of [Pekka] playing the very first level of Quake.
Thanks to: [Mr. Jay], [james], [gudenau], [AltMarcs], [Alogus], [Daniel] as well as last however not least [ProfFartSparkles] who all truly desired us to function this hack as well as sent in a tip.