Editing Talk:Engine bug (section) From DoomWiki.org Warning: You are not logged in. Your IP address will be recorded in this page's edit history. Anti-spam check. Do not fill this in! == Lower unpeg + sky hack == There is in Doom a hack that, according to the comment, is needed for height changes. This all happens in {{c|R_StoreWallRange}}. First, two values are defined, at separate places in the code but I'll put them together here: worldtop = frontsector->ceilingheight - viewz; worldhigh = backsector->ceilingheight - viewz; So, worldtop is the front sector's height, and worldhigh is the back sector's. // hack to allow height changes in outdoor areas if (frontsector->ceilingpic == skyflatnum && backsector->ceilingpic == skyflatnum) { worldtop = worldhigh; } But it has a side-effect for lower-unpegged textures: if (worldlow > worldbottom) { // bottom texture bottomtexture = texturetranslation[sidedef->bottomtexture]; if (linedef->flags & ML_DONTPEGBOTTOM ) { // bottom of texture at bottom // top of texture at top rw_bottomtexturemid = worldtop; } else // top of texture at top rw_bottomtexturemid = worldlow; } Lower-unpegged textures use the "worldtop" (front) value, and this hack has set it to "worldhigh" (back) instead of what it should be without the hack. So in an outside area, lower-unpegged textures are aligned according to their back sector instead of their front sector. To me, this looks like a bug as I don't believe "allowing height changes in outdoor areas" translates to "changing the way lower unpegged textures work" and it can break texture alignment. Some source ports with a renderer not derived from Doom's original software renderer may also miss this entirely (this is notably the case for GLBoom+ and Eternity), while others like GZDoom take it into account and imitate vanilla's discrepancy. Questions: 1. How to call it, "Lower-unpegged inconsistency in outside sectors"? 2. Would this be disputed or undisputed as a bug? 3. Why do height changes require this hack exactly? --[[User:Gez|Gez]] ([[User talk:Gez|talk]]) 22:01, 9 May 2015 (UTC) : 1. How about "Lower unpegged inconsistency in sky sectors"? It avoids a hyphen which I don't feel is necesssary, and also is more explicit about what triggers the problem (versus "outside" which is vague even if probably obvious to most Doom editors). 2. I hate having that field on this article, as has been discussed several times before, so I am not sure how or if I want to answer that. 3. I have no idea and, if I did, Eternity certainly wouldn't have been broken all these years. I really don't know how it has gone unnoticed for so long. --[[User:Quasar|Quasar]] ([[User talk:Quasar|talk]]) 22:12, 9 May 2015 (UTC) Summary: All contributions to DoomWiki.org are considered to be released under the CC BY-SA 4.0 International (see Doom Wiki:Copyrights for details). By contributing, you agree to be bound by the Terms of Use. Your changes will be visible immediately. Please enter a summary of your changes above. Do not submit copyrighted images or text without permission! This includes text taken from in-game codices or logbooks, or from official instruction manuals, strategy guides, and other such books. This project is not affiliated with id Software, Raven Software, ZeniMax Media, Bethesda SoftWorks, or any other commercial software developer or publisher. Use of trademarked logos and other protected intellectual property is solely for the purpose of analysis and critical commentary on the identified products and associated fan community activity, and does not imply any endorsement by any of these organizations or their employees, past or present. Upload images to the wiki. Don't forget to categorize pages! For testing, please use a sandbox. View this template Cancel | Editing help (opens in new window)