It is definitely not symmetrical , not even close, and this is disregarding the additional height added by the minimap and move/attack/patrol HUD, which makes it even worse. When it centers your vision, the amount you can see above the center point is substantially more than what you can see below, even checking at the horizontal center. Check the distances on either side and of course it's even worse.
To better illustrate the problem he's having, for anyone not entirely sure what he's talking about, I'll supply some visuals.
1) I've centered view on a location here. The patch of water is dead center.
2) The blue outline here shows the outline of the location.
3) The red lines mark the horizontal and vertical centers.
4) Finally, the main square of terrain being centered on has been highlighted in green.
The issues here are abundant. For one, you can see that the terrain tiles do not match up with the screen. There is 1/3 a tile of terrain visible at the top of the screen, above the location. There is also about 1/3 a tile of terrain at the bottom center, and 1/2 a tile above the bottom left.
Second, the 1/3 tiles are not the same distance from the center. As you can see above in the green highlighted area, the entire square is visible at the top along with 1/3 tile of extra terrain above that, while only 1/3 of the bottom row of the same square is visible.
This is the problem which he is trying to overcome.
As for a solution, the only way to fix it is to make the camera center at a point below where the unit is actually at, as others here have been discussing methods of accomplishing. I wish you the best of luck in this because it's quite a troublesome thing to get around. Chances are good that you will end up redesigning the map to take this issue into account, rather than managing to solve the issue itself in a practical way.
Post has been edited 3 time(s), last time on Oct 12 2010, 12:23 pm by DevliN. Reason: Mineral abuse.