Skip to main content

Speed improvements.

Yesterday was headache day, so no development.

Today was coding day. Found a big BUG!

I've been using a dictionary to contain my navigation data, that's to remove the need to recalculate the graph after every run of A*. I just made a deep copy of the original dictionary. I was deep copying the dictionary, then cropping the new dictionary to a bounding box around the start and finish points, by reducing the size of the graph it makes A* run faster.

Unfortunately deep copy, or even dict.copy() are very slow operations.

So while a long distance calculation of A* was taking 0.012 seconds, the deep copy operation was taking 0.12 seconds! 10 times slower than the A* function. A big drain on resources indeed. (nearly half a second for just six enemies!)

So I started by rewriting the cropping function. Now it crops data out of the original dictionary, copying entries and appending them to a new dictionary. Because it only copies entries inside the bounding area this is much faster and the resulting graph is much smaller. This takes just 0.01 seconds, much better and still somewhat faster than rebuilding the graph from scratch every time.

I've also done some work with the AI so it won't try to move if there's no route. It gets this info from the AI tactical map, though this is another area that is a little slow to calculate, but improved 10 fold since last week.

AI maps themselves are coming along rather nicely:

LOS is now calculated for each player character and also a fleeing map, so the enemies can get away to an unseen region. Archers will be able to move to a distant spot where the Player can still be seen and fire from there. If you pull out a bow and start shooting, enemies will take cover if far away, or move to engage quickly if they are close by. The more complex I make this part of the game, the slower the AI turns are going to be, so I have to find a compromise.

Again, cropping the area of calculation to include only the active players and a moderate border should speed things up. While allowing me to make the AI a little smarter. At the moment it only calculates areas which are accessible, i.e. not behind shut doors viewable. That's very fast but it means you can seal an enemy in a room and it won't move or do anything until the door is opened again. You could also avoid enemies by not looking at them. This obviously needs to be changed.

The AI maps are not very useful for the player, but they could be rewritten to use different calculations during the player's turn. LOS is useful for simulating guards, while accessibility maps can be used to make sure an A* pathfinding check isn't run if there's no valid route to that point, thus saving time.

One thing I have to look at is how opening a door during the AI turn immediately requires a re-run of the AI map generator if it makes new areas visible or accessible to the player's characters.

More experiments and refinements tomorrow.

Comments

Popular posts from this blog

Make your game models POP with fake rim lighting.

I was watching one of my son's cartoons today and I noticed they models were using serious amounts of simulated rim lighting. Even though it wasn't a dark scene where you'd usually see such an effect, the result was actually quite effective.



The white edge highlighting and ambient occluded creases give a kind of high contrast that is similar to, but different from traditional comic book ink work.


I'll be honest, I don't know if there's a specific term for this effect in 3d design, since my major at university was in traditional art. I learned it as part of photography.


You can find plenty of tutorials on "what is rim lighting" for photography. It basically means putting your main sources of light behind your subject so that they are lit around the edges. It can produce very arresting photographs, either with an obvious effect when used on a dark subject...


..,or as part of a fully lit scene to add some subtle highlights. See how alive the subject look…

How to... build a strong art concept.

So you want to make some art assets for your game. The first on the list is a Steampunk Revolver for your main character to shoot up Cthulhu with. Quickly opening your internet browser you start with a Google image search. Ah, there is is!

It might be a good idea to find a few influences so you don't accidentally end up copying a famous design.


Just mash them up and you're ready to go! Off to your favorite modeling program.
But wait! isn't there more to building a strong design concept than that?

Of course there is.
One of the diseases of modern design is that of recursion. Everything is a copy of a copy of a copy. This is especially a problem with "historical" concepts. Over the course of that recursive process the concept becomes infected with modern design elements, and ends up looking very similar to everything else that anyone else has ever made.
If you want to come up with a really fresh idea, you have to get beyond secondary references and go look at real …

Rockets

I finished working on the code for adding foliage and having some extra time I decided to experiment with the code for rockets.

The original idea I had was that rockets would be large vehicle components that can be fired very quickly, regardless of how much manpower is used for reloading.






They would use up a lot of ammo, so they would run dry after a short but devastating barrage.
The problem here is that it's easy to take advantage of this by adding a lot of ammo, which is much smaller than in bulk than the rockets.

There's also the problem of firing large caliber rockets. In real life rockets of up to 30cm were used, but I think that will be too powerful for the scale of combat in this game.



lol. Somehow that one trooper survived the mother of all explosions...

A 30cm rocket could contain nearly 30KG of explosive. That would be a very large explosion.

I've tried to balance the game by using a simple equation to make bigger guns more powerful, but hopefully not too powerf…