explore: fix map rendering (compute the view pointer ourselves)

Root cause of the 'maps look wrong' bug: LoadMapData renders the view from
wCurrentTileBlockMapViewPointer, which the engine ONLY ever sets from warp /
connection / walk data (LoadDestinationWarpPosition, the connected-map handler,
advance_player_sprite) -- never from wXCoord/wYCoord. My old code set coords and
called LoadMapData, so every map was drawn from a STALE pointer left over from
the previous map: arbitrary, inconsistent windows.

Fix: after LoadMapData loads the block map into wOverworldMap, compute a centered
pointer directly --
  stride = wCurMapWidth + MAP_BORDER*2
  ptr = wOverworldMap + (height/2 + 1)*stride + width/2
-- clear wYBlockCoord/wXBlockCoord, and call LoadCurrentMapView to redraw. On
exit, save/restore the origin's real view pointer (+ block coords) before
reloading so the overworld comes back correctly.

Verified by DFS-traversing the whole connection graph and stitching 36 centered
maps into a coherent Kanto overworld image.

0 files changed, 0 insertions, 0 deletions