fix superclip renderer

Include world center point. Fixes Warbirds horizon.

lynx/susie.cpp

@@ -649,8 +649,8 @@ ULONG CSusie::PaintSprites(void)
          int screen_v_start=(SWORD)mVOFF.Word;
          int screen_v_end=(SWORD)mVOFF.Word+SCREEN_HEIGHT;
 
-         int world_h_mid=screen_h_start+0x8000+(SCREEN_WIDTH/2);
-         int world_v_mid=screen_v_start+0x8000+(SCREEN_HEIGHT/2);
+         int world_h_mid=screen_h_start+(SCREEN_WIDTH/2);
+         int world_v_mid=screen_v_start+(SCREEN_HEIGHT/2);
 
          TRACE_SUSIE2("PaintSprites() screen_h_start $%04x screen_h_end $%04x",screen_h_start,screen_h_end);
          TRACE_SUSIE2("PaintSprites() screen_v_start $%04x screen_v_end $%04x",screen_v_start,screen_v_end);
@@ -672,7 +672,7 @@ ULONG CSusie::PaintSprites(void)
          // Check ref is inside screen area
 
          if((SWORD)mHPOSSTRT.Word<screen_h_start || (SWORD)mHPOSSTRT.Word>=screen_h_end ||
-               (SWORD)mVPOSSTRT.Word<screen_v_start || (SWORD)mVPOSSTRT.Word>=screen_v_end) superclip=TRUE;
+            (SWORD)mVPOSSTRT.Word<screen_v_start || (SWORD)mVPOSSTRT.Word>=screen_v_end) superclip=TRUE;
 
          TRACE_SUSIE1("PaintSprites() Superclip=%d",superclip);
 
@@ -719,7 +719,7 @@ ULONG CSusie::PaintSprites(void)
             // line, BUT on superclip we draw all the way to the end of any
             // given line checking each pixel is on screen.
 
-            if(superclip & 0) {
+            if(superclip) {
                // Check on the basis of each quad, we only render the quad
                // IF the screen is in the quad, relative to the centre of
                // the screen which is calculated below.
@@ -749,16 +749,16 @@ ULONG CSusie::PaintSprites(void)
 
                switch(modquad) {
                   case 3:
-                     if((sprite_h>=screen_h_start || sprite_h<world_h_mid) && (sprite_v<screen_v_end   || sprite_v>world_v_mid)) render=TRUE;
+                     if((sprite_h>=screen_h_start || sprite_h<=world_h_mid) && (sprite_v<screen_v_end    || sprite_v>=world_v_mid)) render=TRUE;
                      break;
                   case 2:
-                     if((sprite_h>=screen_h_start || sprite_h<world_h_mid) && (sprite_v>=screen_v_start || sprite_v<world_v_mid)) render=TRUE;
+                     if((sprite_h>=screen_h_start || sprite_h<=world_h_mid) && (sprite_v>=screen_v_start || sprite_v<=world_v_mid)) render=TRUE;
                      break;
                   case 1:
-                     if((sprite_h<screen_h_end   || sprite_h>world_h_mid) && (sprite_v>=screen_v_start || sprite_v<world_v_mid)) render=TRUE;
+                     if((sprite_h<screen_h_end    || sprite_h>=world_h_mid) && (sprite_v>=screen_v_start || sprite_v<=world_v_mid)) render=TRUE;
                      break;
                   default:
-                     if((sprite_h<screen_h_end   || sprite_h>world_h_mid) && (sprite_v<screen_v_end   || sprite_v>world_v_mid)) render=TRUE;
+                     if((sprite_h<screen_h_end    || sprite_h>=world_h_mid) && (sprite_v<screen_v_end    || sprite_v>=world_v_mid)) render=TRUE;
                      break;
                }
             } else {