Talk:Venetian blind crash

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Now that both articles have actually been started, this one sounds like the same bug as Segfault/lightning flash near very tall structures.    Ryan W 22:59, 25 June 2006 (UTC)

Hm.  At least, the first paragraph of that article does.  Now that I think about it, the real meaning may be that (a) tall structures are one way of causing overflow, divide by zero, etc., and then (b) that overflow leads to a Venetian blind crash.  Right?    Ryan W 22:02, 26 June 2006 (UTC)
Yes. The tall-structures bug is a completely distinct phenomenon from venetian blind crashes. Anything that crashes DOOM may cause a venetian blind crash in DOOM, although I have on occasion seen it crash differently -- ie, with an actual stack dump from DOS4GW (very rare), or a single line of dark and unintelligible VGA text printed at the top of the screen over an otherwise normal but frozen frame of graphics. As explained in this article, venetian blind crashing is precisely the result one gets under DOS from not properly cleaning up a mess you've made. On the other hand, EE was suffering crashes due to deep holes as recently as the previous official release. --Quasar 05:26, 19 July 2006 (UTC)

The key to fixing most venetian blind crashes in dos is to run mode co 80, this is pretty old, added it to the wiki -zokum.

Horizontality[edit]

Everything in the description -- from the metaphor in the name of the bug, the comparison with scanlines, and the description about "alternating horizontal lines" is in contradiction with the screenshot and the linked video in which the bug causes vertical lines of darkened pixels. Either it's poorly phrased, or the examples given correspond to a different, perpendicular glitch. --Gez 14:27, 11 March 2013 (UTC)

After reading the article in December 2011, I couldn't figure out any other bug than the one displayed in the screenshot (DosBox). Furthermore, before linking the video to the article, I found content where the Venetian blind crash was mentioned. Once the "instructions" in the paragraph were carried out, there was a result identical with that in the screenshot, which enhanced my belief that it is the phenomenon in question. So, if it's not what the writer of the article has come across, at least it is a variant of the same glitch.
As for the horizontality, I interpreted that when the reader starts to move from the left edge of the screenshot towards the right edge, pixel by pixel, there will be regular alternating between black sections and gameplay sections. According to the screenshot, the x-coordinates of the former are 8–9, 16–17, 24–25, ... 616–617, 624–625 and 632–633. Thus, the entire column on a black x-coordinate from the top to the bottom is darkened, which causes vertical lines. But, it's just an interpretation, which shows that it could be explained in a clearer way. --Jartapran 16:18, 11 March 2013 (UTC)
I think it has to do with how vanilla render works with VGA hardware. Notice that you can see the (still working and responsive) DOS shell in the gaps between the "blinds", albeit the text is rather huge and oddly colored - this is a typical sight with fatal crashes of many DOS applications; the "big text bug", as it was poplularly called back in the day. Unmaker 21:44, 11 March 2013 (UTC)