Tweak the behavior of viewscreens to what is more logical IMO.

- At a given time, at most one viewscreen may display TILE_VIEWSCR, namely
  that one which is g_curViewscreen
- sync kinds of distance to compare against VIEWSCREEN_ACTIVE_DISTANCE (was
  Manhattan vs. dist(), now both the latter)
- fix resetting to VIEWSCREEN tile when player is greater from it than that
  distance. When the player is closer to it again, it is *not* reset to
  TILE_VIEWSCR.
- more sync'd g_curViewscreen and sprite[i].yvel (for 'i' being the viewscreen
  sprite)

Note: in a multiplayer context, this needs to be thought about once more.

git-svn-id: https://svn.eduke32.com/eduke32@4843 1a8010ca-5511-0410-912e-c29ae57300e0

polymer/eduke32/build/src/polymost.c

@@ -3872,6 +3872,8 @@ void polymost_drawsprite(int32_t snum)
         }
         else if (tspr->cstat & 32)
         {
+            // XXX: such a z offset can be relatively large; for a given
+            // tsprite, not independent of the rest of the scene.
             if ((tspr->z - sec->ceilingz) < (sec->floorz - tspr->z))
                 tspr->z += snum;
             else tspr->z -= snum;

polymer/eduke32/source/actors.c

@@ -2232,21 +2232,25 @@ DETONATE:
             if (s->xrepeat == 0)
                 KILLIT(i);
 
-            A_FindPlayer(s, &x);
-
-            if (x < VIEWSCREEN_ACTIVE_DISTANCE)
             {
-                if (SP == 1)
+                const int32_t p = A_FindPlayer(s, &x);
+                const DukePlayer_t *const ps = g_player[p].ps;
+
+                if (dist(&sprite[ps->i], s) < VIEWSCREEN_ACTIVE_DISTANCE)
+                {
+#if 0
+                    if (sprite[i].yvel == 1)  // VIEWSCREEN_YVEL
                         g_curViewscreen = i;
+#endif
                 }
-            else if (g_curViewscreen != -1 && T1 == 1)
+                else if (g_curViewscreen == i /*&& T1 == 1*/)
                 {
                     g_curViewscreen = -1;
+                    sprite[i].yvel = 0;  // VIEWSCREEN_YVEL
                     T1 = 0;
-                //loadtile(s->picnum);
-                //invalidatetile(s->picnum,-1,255);
                     walock[TILE_VIEWSCR] = 199;
                 }
+            }
 
             goto BOLT;
 

polymer/eduke32/source/game.c

@@ -7163,7 +7163,7 @@ static inline void G_DoEventAnimSprites(int32_t j)
 
 void G_DoSpriteAnimations(int32_t ourx, int32_t oury, int32_t oura, int32_t smoothratio)
 {
-    int32_t j, k, p, sect;
+    int32_t j, k, p;
     intptr_t l;
 
     if (spritesortcnt == 0)
@@ -7317,6 +7317,8 @@ void G_DoSpriteAnimations(int32_t ourx, int32_t oury, int32_t oura, int32_t smoo
         if (t->statnum == TSPR_TEMP)
             continue;
 
+        Bassert(i >= 0);
+
         {
             int32_t snum = P_GetP(s);
             const DukePlayer_t *const ps = g_player[snum].ps;
@@ -7339,9 +7341,8 @@ void G_DoSpriteAnimations(int32_t ourx, int32_t oury, int32_t oura, int32_t smoo
             }
         }
 
-        sect = s->sectnum;
+        const int32_t sect = s->sectnum;
 
-        Bassert(i >= 0);
         curframe = AC_CURFRAME(actor[i].t_data);
 #if !defined LUNATIC
         scrofs_action = AC_ACTION_ID(actor[i].t_data);
@@ -7435,7 +7436,7 @@ void G_DoSpriteAnimations(int32_t ourx, int32_t oury, int32_t oura, int32_t smoo
                 t->xrepeat += 8;
                 t->yrepeat += 8;
             }
-            else if (g_curViewscreen >= 0 && OW != i && display_mirror != 3 && waloff[TILE_VIEWSCR] && walock[TILE_VIEWSCR] > 200)
+            else if (g_curViewscreen == i && display_mirror != 3 && waloff[TILE_VIEWSCR] && walock[TILE_VIEWSCR] > 200)
             {
                 // this exposes a sprite sorting issue which needs to be debugged further...
 #if 0
@@ -7457,11 +7458,6 @@ void G_DoSpriteAnimations(int32_t ourx, int32_t oury, int32_t oura, int32_t smoo
                 t->yrepeat = t->yrepeat & 1 ? (t->yrepeat>>2) + 1 : t->yrepeat>>2;
             }
 
-#if 0 // moved to polymost
-            t->x += (sintable[(t->ang+512)&2047]>>13);
-            t->y += (sintable[t->ang&2047]>>13);
-            updatesector(t->x, t->y, &t->sectnum);
-#endif
             break;
 
         case SHRINKSPARK__STATIC:

polymer/eduke32/source/sector.c

@@ -2828,7 +2828,7 @@ CHECKINV1:
                             p->holoduke_on = i = A_InsertSprite(p->cursectnum,p->pos.x,p->pos.y,
                                                                 p->pos.z+(30<<8),APLAYER,-64,0,0,p->ang,0,0,-1,10);
                             T4 = T5 = 0;
-                            SP = snum;
+                            sprite[i].yvel = snum;
                             sprite[i].extra = 0;
                             P_DoQuote(QUOTE_HOLODUKE_ON,p);
                             A_PlaySound(TELEPORTER,p->holoduke_on);
@@ -3220,11 +3220,12 @@ void P_CheckSectors(int32_t snum)
                 {
                     if (PN == CAMERA1 && SP == 0 && sprite[neartagsprite].hitag == SLT)
                     {
-                        SP = 1; //Using this camera
+                        sprite[i].yvel = 1;  // Using this camera
                         A_PlaySound(MONITOR_ACTIVE,p->i);
 
                         sprite[neartagsprite].owner = i;
-                        sprite[neartagsprite].yvel = 1;
+                        sprite[neartagsprite].yvel = 1;  // VIEWSCREEN_YVEL
+                        g_curViewscreen = neartagsprite;
 
                         {
                             int32_t j = p->cursectnum;