Difference between revisions of "Chapter 3"

Revision as of 12:26, 29 May 2009

(incomplete)

NPC Evolution

Remember in Chapter 1 when we looked at that basic NPC script? It was a generic script to create a naked man (or a naked player). And it looked something like this:

[CHARDEF 0190]
DEFNAME=c_man
Name=Man
ICON=i_pet_MAN
CAN=MT_EQUIP|MT_WALK|MT_RUN|MT_USEHANDS
RESOURCES=i_flesh_head, i_flesh_torso, i_flesh_right_arm, i_flesh_left_arm
FOODTYPE=15 t_food, t_fruit
DESIRES=i_gold,e_notoriety
AVERSIONS=t_TRAP,t_eerie_stuff
SHELTER=r_house
BLOODCOLOR=0

TSPEECH=spk_human_prime
TSPEECH=spk_human_default
TEVENTS=e_Human_HearUnk
DESCRIPTION=Man
SUBSECTION=Miscellaneous
CATEGORY=Civilized

As you can see, this is a rather incomplete script. It's actually one of the least complete of any of the scripts available in the spherechar_*.scp files. Here is a more complete example of an NPC script:

[CHARDEF 0490]
DEFNAME=C_H_ALCHEMIST
NAME=#NAMES_HUMANMALE the Alchemist
ID=C_MAN

DESIRES=i_gold,e_notoriety,t_magic
AVERSIONS=t_TRAP,t_eerie_stuff

TSPEECH=spk_human_prime
TSPEECH=jobalchemist
TSPEECH=spk_shopkeep
TSPEECH=spk_needs
TSPEECH=spk_rehello
TSPEECH=spk_human_default

TEVENTS=e_Human_HearUnk
TEVENTS=e_Human_ConvInit
TEVENTS=e_Human_Greet
TEVENTS=e_Human_Space
TEVENTS=e_Human_Needs
TEVENTS=e_Human_Refuse
TEVENTS=e_Human_Environ

CATEGORY=Civilized
SUBSECTION=Tradesmen
DESCRIPTION=Alchemist (male)

ON=@Create

SELL=VENDOR_S_ALCHEMIST

BUY=VENDOR_B_ALCHEMIST

[CHARDEF 0490] We've seen this before. It says "Hey SPHERE! Everything after this line until the next header is going to define a character!" What is this character going to be? Well, right now we have no idea, it's just 0490 to SPHERE. The 0490 also shows the client what anim to show (except for monsters with the ID field, wich will show the ID field anim). You can also use the char defname in the [CHARDEF x] field instead of a number (wich is better for new npcs), for example: [CHARDEF c_new_monster]

DEFNAME=C_H_ALCHEMIST This is the defname for this script, obviously. We've seen things like this so many times, I don't believe I need to go over it. But now at least we have a more memorable name for this script. It's obviously a character (C), a human (H), and an alchemist (C_H_ALCHEMIST). Try to make your DEFNAMEs make sense based on what the character is. Calling this c_robed_man would have absolutely no memorable qualities.  :)

NAME=#NAMES_HUMANMALE the Alchemist This is where SPHERE does some funky stuff. First of all, if you remember from the SPHERE_NAME.SCP lesson in Chapter 2, it is going to replace #NAMES_HUMANMALE with an actual name for this NPC, such as "Fritz", "Bob" or the ever popular "Roderick". The second thing it is going to do is divide this name into a NAME and a TITLE. Where does it do this division? At the word "the". So writing this line is equivalent to:

NAME=#NAMES_HUMANMALE
TITLE=the Alchemist

ID=C_MAN Here is where we actually tell SPHERE what this thing is. What is C_MAN? It's a DEFNAME obviously, but for what? Look up toward the top of this file, and you'll see the definition of the C_MAN character.

And so on. As you can see, we're just duplicating what we've written in the previous section. But with the newer versions of SPHERE we don't need to do that. Our character 0490 automatically gets everything that comes default on a C_MAN, including abilities, icons, and sounds, UNLESS WE SAY OTHERWISE. In programming, this is called inheritance. The new, more specific character inherits the properties of the less specific one.

You'll notice that we respecify DESIRES and AVERSIONS. Why do we do this if C_MAN has already told us what this type of character wants and doesn't want? Well I'm not sure in the case of AVERSIONS, because, well, they're the same. But the DESIRES of an alchemist are different than the DESIRES of a generic man, so we tell SPHERE, "Hey, replace the C_MAN desires with our new ones!"

TSPEECH= What do you suppose those cryptic names are following this statement? Of course, they're DEFNAMEs, but for what? If you look through your files, chances are you won't find those defined anywhere.. But what's this? We have a folder called speech that comes preconstructed in the zip file. Looking through those files reveals a wealth of [SPEECH] block definitions. The default ones can be found at the SPEECH folder on your scripts folder.

We'll look at a very simple speech script right now. I am not taking this from any file.

[SPEECH spk_human_test]
ON=*hello*
SAY Cheese!

In our script, if we were to write TSPEECH=spk_human_test, our NPC would respond with "Cheese!" any time we said "hello" to him. You might be wondering why I have surrounded this word with stars (*). In programming lingo, a star means "ANYTHING". So you could say "I want to eat you hello goodbye" and the NPC would still respond with "Cheese!", because the word "hello" was present.

Of course, SPEECH is much more complicated than that and we'll look at it again when we reach the chapter on basic event scripting. Just know for now that you can have as many TSPEECH lines as you wish in a CHARDEF section.

TEVENTS= We've already covered this in a very very tiny amount of detail in Chapter 1. This is where events for the creature are defined. As you can see, this creature contains a great deal of events. They define everything from what he says when he hears an unknown word ("Huh?"), to what he does when he sees a new player. We'll look at an event script in Chapter 8. You should learn the basics of item scripting before you try NPC event scripting. For now just know that you can retrieve all the TEVENTS of a npc by using <[REF].TEVENTS>.

ON=@Create Actually, I lied. @Create is an event, and we're going to talk about it right now. But it's a special event, as is the next one we're going to discuss. Basically, @Create causes every line after it to be processed (the entire section highlighted in red) when an object is Created. Creative eh? (Ha, ha.) In this case, I'm not going to concentrate on most of the lines following, as they should all make sense to you now. All you need to know at this point about @Create is that things you can change IN GAME go under this section. This includes stats, skills, unlootable items, colors, brain types, and TAGs (Although tags can be defined on CHARDEF too, it's a great way to set a tag to all npcs with that chardef without needing to do a restock or change one by one) (You don't know what a TAG is? Good, I haven't taught you yet.).

ALCHEMY={55.0 77.0} This line is very deceiving, and the reason for the deception is the way that SPHERE processes numbers. SPHERE cannot, ever, read a decimal number. 55.0 means nothing to SPHERE, and it simply strips out the decimal point. Now, isn't it convenient that internally, skills are stored as big numbers? Look at your skills menu in-game right now. Find a skill that isn't zero, obviously, and look at the value.

It looks like this: 42.0

Now, in-game again, type this command: .set [skillname] 42 (Of course, replacing [skillname] with the skill of your choice. Refer to spheretables.scp if the name you're typing doesn't work.) What happened? Your skill suddenly went to 4.2!! Is this an error in the game? No, actually it's because skills are stored by removing the decimal point. If you have 100.0 in blacksmithing, your skill is actually set to 1000. If you have 75.2 in a skill, that skill is 752.

This may seem like a simple concept, but it also applies to the REST of scripting as well. Any time you type a number like 55.0, SPHERE eliminates the decimal. So our example line above is actually this:

ALCHEMY={550 770}

Isn't that sneaky?

One of the times you might want to remember this is later, if you are multiplying numbers:

4 * 0.5

Sphere translates this as "4 times 5" and you get 20, rather than the 2 you were expecting. As you can see, this may cause serious problems. I'll show in later chapters how to get around this problem. I just wanted to point out here that it exists. (Look back at the resource tables in sphereregion.scp for another example of where sneaky decimal points are used.)

NPC=brain_vendor Ok, so I'm out of order. Deal with it.

All NPCs in the game are controlled by specific intelligences, which direct the way they act in certain situations. For instance, this alchemist is a brain_vendor, which means he responds to commands like "buy" and "sell" by opening up a trade window. It also means that he is allowed to have extra storage space for information dealing with the items he can buy and sell. (Actually they are additional containers stored on the vendor, but we shall see that later.) Here is a list of the other intelligences available (I bet you can't guess which file I pulled this from):

[DEFNAME brains]
BRAIN_NONE 0 // Players: No brain. Convenient eh?  :)
BRAIN_ANIMAL 1 // Animals: wander, attack only if attacked
BRAIN_HUMAN 2 // Human: wander and speak
BRAIN_HEALER 3 // Healer: heal ghosts in proximity
BRAIN_GUARD 4 // Guard: attack bad guys I see
BRAIN_BANKER 5 // Banker: you can access your bank through him
BRAIN_VENDOR 6 // Vendor: buys and sells things
BRAIN_BEGGAR 7 // Beggar: follows players around asking irritating questions
BRAIN_ANIMAL_TRAINER 8 // Trainer: can stable animals
BRAIN_THIEF 9 // Thief: no effect right now
BRAIN_MONSTER 10 // Evil: attack all players we see
BRAIN_BESERK 11 // Crazy: attack anything we see
BRAIN_UNDEAD 12 // Undead: same as evil, just used for identification
BRAIN_DRAGON 13 // Dragon: breathes fire (set this on a rabbit)
BRAIN_VENDOR_OFFDUTY 14 // No idea what the difference is here
BRAIN_TOWNCRIER 2 // Same number as brain_human, same effect
brain_beserk brain_berserk //Same thing as brain_berserk, just to avoid some errors by typos

ITEMNEWBIE= This creates the specified item with the attr_newbie on the char.

ON=@NPCRestock I lied twice! This is the SECOND event you're going to learn in this script. This event is triggered when a "restock" happens in-game. This occurs once every few real-time hours, or if a staff member types ".sector.restock". What you should put here is anything lootable from this NPC, along with the definitions of things they buy and sell. Once again, this is just a template in most cases, so you should know how to deal with it. I'm going to examine two lines though:

SELL=VENDOR_S_ALCHEMIST
BUY=VENDOR_B_ALCHEMIST

This defines what the vendor buys and sells? But where are these mysterious lists of items coming from? Actually, they're templates, in the file spheretemp_vend.scp. (Templates for vendors. Those developers are so creative.) Actually it's a good thing to name files after what's inside of them.  :)

Price is not defined anywhere on these BUY and SELL lines. Price is defined in a VALUE= line in an individual item script. If an item script does not have a VALUE= line, price is determined by multiplying the value of the resources in that item by the number of resources required. For example, if an item takes 8 iron ingots to make, and each ingot has a VALUE of 8 gold pieces, the entire item is going to be worth 64 gold. By default, things sell for half of the price you can buy them for.

I think that's all you need to know for now about scripting a new NPC. Right now, with your abilities, you can create new vendors, new monsters, and new animals that wander your world. But they don't do anything unique yet. They just behave like stronger or weaker versions of the same monsters. And they're probably pretty colors, too, judging from the recent use of my hues.mul file for colors 077a and 07a1. (I really should release a DEFNAME script for those.)

Now that you know how to make a decent NPC, let's explore ways to make unique items to put on him as loot. In the next section, we're going to make a SUPER DUPER BOW OF FIRE AND BRIMSTONE! *trumpet fanfare*