ItemWorldMap.java

    public WorldMap a(ItemStack itemstack, World world) {

        WorldMap worldmap = (WorldMap) world.a(WorldMap.class, "map_" + itemstack.getData());

        if (worldmap == null) {
            itemstack.b(world.b("map"));
            String s = "map_" + itemstack.getData();

            worldmap = new WorldMap(s);
            worldmap.b = world.q().c();
            worldmap.c = world.q().e();
            worldmap.e = 3;
            worldmap.map = (byte) world.worldProvider.dimension;
            worldmap.a();
            world.a(s, (WorldMapBase) worldmap);
            
            // Insert event here
        }

        return worldmap;
    }

WorldMapHumanTracker.java

            // CraftBukkit start
            for (i = 0; i < render.cursors.size(); ++i) {
                MapCursor cursor = render.cursors.get(i);
                if (!cursor.isVisible()) continue;
                
                byte value = (byte) (((cursor.getType() == 0 || cursor.getDirection() < 8 ? cursor.getDirection() : cursor.getDirection() - 1) & 15) * 16);
                abyte[i * 3 + 1] = (byte) (value | (value < 0 ? 16 - cursor.getType() : cursor.getType()));
                abyte[i * 3 + 2] = (byte) cursor.getX();
                abyte[i * 3 + 3] = (byte) cursor.getY();
            }
            // CraftBukkit end