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

Advice needed on tilesets...

I need some advice on which is the best way to handle building the dungeon. Right now I'm using prefabs for my dungeon, they have a north south east and west section for each "room": The basic tileset. This has several advantages, and also several disadvantages. Firstly I can have curved rooms, I can have tunnels and other interesting shapes. The tilesets can look quite nice with a little work. On the other hand I can't easily get the navigation data before building the map and once the map has been built I can't make changes to the layout, like having active pit traps or believable secret doors. Although the rooms are interesting, they are quite repetitive, and it takes a lot of effort to make even a few different variations. Also rooms are constrained to one size. A newer version of the tileset with a lot of variant parts for making more interesting rooms. To create a tile set is a real headache too. Planning how to lay out the UVs, trying to cra...

Upstairs / Downstairs.

I've decided to make my prefabs multilevel. Later this should allow me to add pit traps and other great stuff. It also makes it easier to line up stairs so that you can exit them on the same co-ordinates where you entered them. The prefab editor is pretty much finished, it just needs some code for loading up prefabs from a saved dictionary, so that they can be checked or edited. The entries will need to be forwards compatible, so I'll be loading each tile and then translating the indexes to a new array, that way if I add extra indexes or extra info (like traps or puzzles) I'll be able to update existing prefabs to work with the new standard. Click for a video.

Video Diary 8

Things are moving along well, there's been a lot of progress on the action manager side of things. Actions have finally moved to the UI, so you can initiate actions by clicking the appropriate button. I've set up some dummy actions to show what happens visually when actions are taken, but the actual dice rolls and such are yet to be integrated. The UI objects are also being added, though some are non functional or empty at the moment. Click on the image to see this week's development video. Every time I add something big I also add about a dozen small things. Like the selection box visualization. Previously this was using render.drawline, and old fashioned Blender function which can be impossible to see at certain resolutions, or at certain frequencies. I replaced it with a function that adds planes of the right size and scale in the right location. I also made all characters a little bigger. I still need to do some work with vectors and final target locations t...