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Oh, dang, I was hoping you were doing something slightly more sophisticated like hooking writes to the frame buffer

Yes as it is the legislative capital. The question was framed along the lines of “name the south asian island nation whose capital is ‘Colombo’” to which my answer was of course Sri Lanka.

www.boredpanda.com/nobody-wants...

Very very cool.

Now we just need an easy way to replay Moraff's Revenge! :)

This is very cool, thank you for making and sharing it!

it would be even cooler if you included another screen that's the whole addressable space and you show read/write as different colors. we could see where sprites are being read from etc.

That's rad

Bro hit me with the Carmen Sandiego, I was not ready.

You could run the CPU at full speed but make each write to video memory take a gigantic amount of time? That way the gameplay will be normal speed.

That's so cool.

That's pretty cool.

This is COOL!

>> stretched aspect ratio

I remember there was a whole account dedicated to creating and posting these regularly, but I can't seem to find it here or on mastodon. Unless I misremember and I only followed it on Twitter.

3) I manually blanked VRAM before doing this experiment, then remapped color 0 to dark purple to highlight that the render engine does not allow horizontal gaps between geometry in the scene, and will fill them in with the background color of space.

Haha I just noticed the menus spell out GOAD

this is so cool I love it

This has scratched my nerd itch for the day. Thank you!

I'm not sure. I think it's doing some trickery with masks/xor that's not super clear from this render. I'll have to dig into it

I used double buffering exclusively once on the PC and would have sworn it was widely done. But maybe I just sucked at preventing flickering when writing to active framebuffers.

It's so beautiful.

test

I was gonna say insect-vision.

This is fascinating! Great visualization!

yep. VGA does support some very basic frame buffer, but this isn't using it

Feels like watching a page load from Prodigy over 2400 bps.

It's been 84 years... since I played this on a friend's Compaq Portable III

Reminds me of those text adventures with graphics e.g. The Hobbit on the ZX Spectrum - they would draw the graphics in a similar fashion (draw lines then add the colors via flood fills).

How it used to actually render real time like on the C64. Funny to see the cursor getting a constant refresh.

Reminds me of playing Legend of the Red Dragon on a BBS with like a 14.4 modem. 😄

yeah! Where in the World is Carmen Sandiego? (Enhanced, 1990, DOS)

the GUI system they're using (I'm just calling it the broderbund UI in my reverse engineering work) DOES support avoiding this mess: you can tell it to hide the cursor, then when each sub-command tries to hide/restore it, it stays hidden, but they're not using it here.

Any idea what would happen if you were moving the mouse while this was happening?

i love that they redraw the mouse cursor multiple times probably unnecessarily. and they paint mouse cursor mask first, and then paint the cursor over it too, instead of doing a single pass. very insightful.

That's brilliant! It really showcases how the games render, i wonder if the sorting order was taken in mind by developers or if it's just simple system limitations.

reminds me a bit of my old VTech Socrates, which would play out elaborate animations of each background being drawn using line and fill tools you could skip them, which makes me wonder whether the animations were for show and it could do those operations instantly, or if they were cached in the ROM

yup

Yeah, at its purest form DOS (including MS-DOS because there are *differences* between DOS-type systems of that era that I am not at all qualified to explain - something something IBM) has no need for mouse support. Drivers were made to add such later on, but the command prompt itself has no need to

A similar thing I did out of curiosity many years ago was hack DOSBox to dump EGA video memory on every frame, so I could see how various games implemented scrolling. Commander Keen 1 was famous for pioneering EGA scrolling, but CK4 refined it quite a bit.