Editor, Fog of War

The editor saves and loads now.  I know it's a stupid little thing, but it was exciting to save a level and open it again.  Also, I tried to make the file browser as convenient as possible.  I even added the path buttons at the top (a button for each folder; if the user clicks one, it backs up to that folder).  However, the scrollwheel doesn't scroll the listbox.  Instead, it just zooms out on the map in the background.  It's not that big of a deal because I can just grab the scrollbar and scroll fast that way, but I forget every time and try to scroll.  It's really annoying.  I think I'll add it just so it stops bothering me.

I tested the editor by making a level with the player and the opponent on opposite sides of the map.  It was exciting to actually play a map created with the editor.  However, there was an issue that I hadn't run into before.  Previously, I always had the player and the AI really close to each other on the map, so I didn't have to zoom out so much to see what was going on.  However, with the players so far apart, I zoomed out quite a bit on the new map.  Unfortunately, this meant that it was displaying alot more fog of war than usual.  This was a problem.

The way I implemented the fog of war was using a simple grid.  Initially, every square in the grid is considered unexplored.  When a new node is built, a circle is drawn in the grid, marking each square in the circle as explored.  When the fog of war is drawn, it just draws a black square on the unexplored squares.  When zoomed out over a large map, that's alot of squares to draw!  The framerate dropped considerably.

I searched the internet for solutions.  One said to stop the camera if it tries to enter unexplored parts of the map, so you don't even have to draw any fog of war.  That's a hack, in my opinion.  Plus, it would be a pain to play the game with that constraint.  However, that's the only optimization I could really find for actually "drawing" the fog of war.  There were plenty of articles about everything else concerning fog of war.  Maybe if I looked for a few more hours, I would have found something.  However, I was tired of looking.

I had an idea that I wanted to try.  I saw that there were big portions of the map that were completely covered in fog, and you could cover most of it with one big rectangle.  So I decided to try to fill up the fog with as many big rectangles as possible, and fill in the rest with smaller rectangles, thereby reducing the number of sprites to draw.  I wasn't sure if it would be faster because it was more processing (though the algorithm is as optimized as it can be), but when I tried it, it was lightning fast!  Fog of war no longer even comes close to lowering the framerate at all, even when zoomed out all the way.

I was really surprised that I didn't see this trick online.  I'm sure it's somewhere out there, but it should be more common because it worked extremely well for me.

My next step, I think is to put some work into the AI.  My currently AI doesn't path-find well enough for most of the maps that I'll be making, so I'll be improving that.

Thanks for reading!
clevceo