Fix automap marks dissapering near left side of the screen

[JNechaevsky]

Fixes this case in widescreen mode:

crispy-doom.2023-12-17.17-49-01-406.mp4

Hovewer! There is a small problem with Doom, caused by flipscreenwidth. This is won't happent if just CXMTOF(pt.x) will be used. Note how 1 is blinking and appearing when it shouldn't. It was happening even before my fix.

crispy-doom.2023-12-17.18-45-56-925.mp4

Not sure how to fix this blinking, no ideas yet... 🤔

[fabiangreffrath]

LGTM, thanks!

[JNechaevsky]

Allow me please to break head more on flipscreenwidth issue, I don't want to leave this blinking. Marks itself are pretty useful when playing less familiar levels, for cases like "leave mega armor for next level, but mark it to don't loose it".

[JNechaevsky]

Hm, this seems to be working fine and fixing marks blinking in both normal and -fliplevels modes:

 void AM_drawMarks(void)
 {
-    int i, fx, fy, w, h;
+    int i, fx, fx_flip, fy, w, h;
     mpoint_t pt;
 
     for (i=0;i<AM_NUMMARKPOINTS;i++)
@@ -2068,10 +2068,11 @@
 	    {
 		AM_rotatePoint(&pt);
 	    }
-	    fx = (flipscreenwidth[CXMTOF(pt.x)] >> crispy->hires) - 1;
+	    fx = (CXMTOF(pt.x) >> crispy->hires) - 1;
 	    fy = (CYMTOF(pt.y) >> crispy->hires) - 2;
+	    fx_flip = (flipscreenwidth[CXMTOF(pt.x)] >> crispy->hires) - 1;
 	    if (fx >= f_x && fx <= (f_w >> crispy->hires) - w && fy >= f_y && fy <= (f_h >> crispy->hires) - h)
-		V_DrawPatch(fx - WIDESCREENDELTA, fy, marknums[i]);
+		V_DrawPatch(fx_flip - WIDESCREENDELTA, fy, marknums[i]);
 	}
     }

I.e., we are drawing mark patch with taking to account possible flipped screen width, but keeping it in strictly original/positive screen bounds (damn, language barriers!).

But I wonder if it could be simplified, such "doubling" doesn't looks nice. Simple fx_flip = (flipscreenwidth[fx]); doesn't work.

[JNechaevsky]

I think it's all done now. To summarize, this PR making two things:

• Fixes possible mark dissapearing and blinking in both normal and flipped levels mode.
• Fixes "mirrored" map panning by mouse movement left-right in flipped levels mode.

Still don't like that fx_flip doubler, but I don't see any ways to simplify it. @fabiangreffrath, your turn please, when you'll have a minute.

[fabiangreffrath]

Thanks for this! I never realized this was wrong, because honestly, how often do you play with flipped levels? 😁

[JNechaevsky]

Honestly? Pretty rarely and only in vanilla IWADs. But I still remember very well first time effect - dizziness and disorientation. Literally almost hit my face on the corner of the wall while trying to walk out from my room after one hour of playing. That's was quite something!

But it was 2017 I think. Far later, in the end of 2019 in pre- New Year celebration at day job, I have tried expensive VR helmet with some kind of zombie shooter game. While playing everything was okay. But about 10 minutes after, different feeling comes: like I was lost between two realities. It's hard to describe, but something like: eyes are seeing one, traditional scene and surroundings, while brain still thinks that I'm "somewhere else" and do not accepts current reality. But no dizziness and disorientation, just heavily annoying "desync" which was standing for a few hours.

Fortunately, my wife was near by, and walking to home was much easier than it could be. Well, she wasn't wife back then, it was happened just a 6 months later. 🙂

[fabiangreffrath]

Looks good, thank you!