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In between work, sleep, family, home and yard projects, and being sick (all the usual bull-shit cop-out excuses you have all come to expect from me over the years) I have been getting in some work on Goblinson Crusoe.

So, the Great AI Refactor has begun in earnest, and as I suspected it would, it has run its tentacles all throughout the project. Up til now, the enemies have all been running off a script object creatively titled TestRandomWanderAI, which obviously randomly selects between FireShotgun, Melee and Area Heal to cast, and which tries to approach GC if a path presents itself. (The class has, uh... grown, somewhat, since it was first created.) Creation-time conditionals in the class designate some loose class-ish tendencies to favor one or the other of the skills. For example, the red-skinned 'shamans' favor fire and healing, while the blue-skinned 'bruisers' favor melee. I've kept this TestRandomWander component around, because inside it are templates and patterns for many of the actions an AI needs to perform. But it is no longer instanced into any of the enemies. In its place is the more generic AIController component.

AIController supplies a healthy set of generic functions (many of them derived, with refactoring and improvement, from the patterns inside TestRandomWander) that provide common functionality. However, instead of the hard-coded think() method of TestRandomWander, the AIController must be supplied a think() function at creation time. Much of the hard work of abstracting out the think() process was already done; I just needed to formalize the structure of the AIController, and re-factor out some of the behavior into separate think() functions supplied when instancing a mob of a given type. I've now finished specifying the existing shaman, bruiser and looter AIs, as a proof-of-concept for myself, and the new system works well. A great deal of 'test code' and placeholder stuff has vanished, in favor of more flexible, more 'real' code.

However, some expected issues are rearing their heads. So far, I have been operating on a very loose, ad-hoc 'design' for the combat system, as regards stats (which stats? what do they do?), buffs, how damage is specified in skill casts, and so forth. I have purposely kept the system flexible. I don't, for example, have a specific set of damage types in play. Damage types are possible, and I use quite a few of them. For example, all the test fire skills deal some measure of fire and siege damage. And some of the test equipment confers bonuses such as +fire_attack and -siege_defense, as a proof of concept. But any given skill could specify any kind of arbitrary damage type if desired. You could conceivably have a Fireball that does 16 to 47 base points of "happy silt stuffing" damage. This damage would apply, taking into consideration any "happy silt stuffing" attack and defense bonuses, if any. The flexibility has been nice, but I think it's probably time to start nailing down concrete damage types and thus simplifying the combat resolution code.

Additionally, with the addition some time back of the Melee skill, I ran into a conflict. When I first started fleshing out the skill system, along with the set of test skills, I imagined the skill system operating such that each skill had a different specification for each rank of the skill, and the damage ranges for the skill would be encoded in the data description for the skill. For example, a Fireball with one single point (assuming a Diablo 2-style skill point advancement system, as I currently envision) might do 3 to 6 damage, while a L2 Fireball might do 7 to 10. Numbers are for illustrative purposes only. I would list the various ranks of Fireball in an array, index it by the caster's Fireball skill level to get the proper one to cast. Segregating it by ranks this way more easily allows me to add extra 'juicy bits' to higher-ranked skills. For example, adding additional bounces to the bouncing fireball spell, adding some kind of DoT ignition debuff at higher ranks, etc...

The system has worked well, but Melee plays differently. In fact, in most games of this basic nature, Melee plays differently. It makes sense to encode the base damage of a fireball skill in the skill itself, and buff/debuff the final values based on caster stats. However, the base damage of a melee swing typically is determined by the equipped weapon, rather than the skill itself. And so, just like that, the addition of Melee has caused a necessary re-design. All of a sudden, for one particular special skill, I have to obtain the base damage ranges from somewhere else other than the skill description itself. It's a relatively minor issue on the face of it. Just call (?) and obtain melee ranges, where (?) is... And there we have the next issue. I don't have the formalized equipment system in place yet. I have A equipment system in place, but not THE equipment system. The test weapons in place can do things such as switch stance and apply stat buffs/debuffs, but that's it. There is nowhere I can currently call up to ask "what is my base damage range for a melee swing?" That ? just doesn't exist yet. And so, with the melee controller, I have added another set of hard-coded test values, to my shame. I need that melee-ing bruiser to do SOMETHING when he swings. So I hardcode some values, and add yet more items to the TODO list.

Still, these kinds of small-but-annoying issues help to refine the various interfaces between components that make up the guts of a game like this. A simple question of "where do base range values come from?" can have far-reaching implications in your design. So many factors can affect it--weapon type, character level, skill level, etc--and all of these factors can possibly live in different places depending on the structure of your combat-enabled entities.

Additional things have also cropped up in this refactor. At any given time, I have more units on the battlefield now than I used to, and a lot more 'things' happening around the map. So my non-polished UI is really starting to show its cracks. I made a few enhancements, but I still have far to go. For example, I added the capability of highlighting the currently-hovered unit with a halo color of green for friendly units, red for enemies, and yellow for neutrals, in order to help make decisions on the battlefield:


This really helps, especially since I'm using the same goblin model and skin(s) for so many different unit types, both friend and foe. However, I still have not updated the hover UI panel to show things such as health, class/unit type, etc... all the vital information you need to decide whether to approach a unit or run away. (The UI, I fear, is going to continue to haunt me for a long time.)

Another thing that has cropped up is a big one that I have been putting off for awhile: performance. In fact, I've been systematically making this problem worse, with my shader-based shenanigans. But the performance is really starting to become critical now, as I add more units, more lights, and just more stuff in general, to the play field. I've made some preliminary stabs at optimizing things: LoD models and materials, tweaking draw distance to strike a happy medium between tactical awareness and performance, etc... But I am still hitting low double-digits to high single-digits framerate on a depressingly consistent basis, and the visual lag and general unresponsiveness makes it feel janky and rough.

That quad-planar shader, with its 32+ texture samples per light in forward rendering, is just one expensive heavyweight bastard, and I really need to start figuring out how to take back some of my framerate. For now, I have 'disabled' the quad-planar texturing on the vertical surfaces of the hex cells; those are now simply wrapped in a standard diffuse+normalmap texture, with only the cap still receiving the quad-planar. The long and short of it is, the quad-planar shader is probably going to go away. In it's place, I am working on a shader that blends from the diff+normal of the hex pillar's vertical surfaces, to the existing texture blend that occurs on the tops of the hexes. I have decided it probably isn't necessary to permit more than one stone/dirt type on a single hex cell, as long as the 'interesting' blending occurring on the tops remains. And by making that simple adjustment, I can eliminate a metric fuckton of texture samples per light. Even with just the temporary placeholder material with a single rock texture, I have already gained back enough framerate to put me back in the high 20s, low 30s on a fairly consistent basis, and with more LoD refinement I can certainly get even more. Hopefully, I can manage to keep the look-and-feel I have enjoyed so far (if with a few limitations that didn't exist before).

Anyway, just thought I'd drop a few lines to let folks know I am still working on GC, if slowly and extremely painfully.



Some fun things in this shot. I added a code path to these goblin types to enable them to build bridges in order to reach Crusoe. These particular guys are Fireball casters, and I gave them Chain Fireball as well. In this shot, 3 of the mobs started building bridges to get to GC, then one of them randomly chose to cast a Chain Fireball at GC. The chain struck the other two goblins, as well as obliterating a number of already-constructed bridge sections, and triggered a 3-way brawl between the goblin and his now-pissed-off colleagues.

AI is fun.

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I did fire up Programmer's Notepad this morning to start re-refamiliarizing myself with the game. Starting to get back into it, and have a little bit of time this week to do so.

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