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Coding Help
This is a counterpart to the "Mapping Help" thread. If you need help with QuakeC coding, or questions about how to do some engine modification, this is the place for you! We've got a few coders here on the forum and hopefully someone knows the answer.
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Sleep: No No 
implement rounding errors or some other form of sloppy calculations so it will feel just like using qoole! 
Thanks For The Tips 
I got my wad loader working ok and it renders textures from a 570 texture wad just fine. The code is a total mess and I still don't know what that weird 16 byte offset is, but I got Quake textures displaying on screen in sexy Quake colours, so I'm happy for today. Next step will be a map loader :)

I made a map compiler (not to bsp, but to a much simpler format that just uses polygons) before, so I still have some code that can create polys from brushes somewhere. I was going to use that. Pretty sure it uses the clipping method. The first solution sounds difficult :)

this?: http://en.wikipedia.org/wiki/Convex_polytope#Vertex_representation_.28Convex_hull.29


Math on wikipedia is always extremely hardcore sounding. 
Just Had A Look 
at my old brush compiler code and it appears to take a series of 3 planes to generate a vertex and then adds the generated vertex to a vertex list for the each face involved in its calculation. It iterates through this until it's done and looks very inefficient.

But if it works, I don't care :)

When editing a map, most of the brushes just sit there unselected. I would imagine the average user doesn't touch more than a handful at once, and even then most of the operations are probably moves. 
Probability Of Attack 
anyone who's studied this could answer a question?

if i've got a monster who has an 80% chance to attack when his checkAttack function is called:

if (random() < 0.8)
attack!

does that really mean he has an 80% chance to attack at all times? or is it more like 10.7% chance to attack every second? (0.8 ^ 10 since animation rate is 10fps)

probability has always been pretty impenetrable for me. :S

as a result, i tend to rely much more on 'cooldown' (attack_finished) timers to regulate monster attack rates. 
Geometric Distribution 
The code you posted means he has an 80% chance to attack each frame. One of the best ways to understand what this means is to look at the probability that the monster will start attacking before the 2nd, 3rd, 4th frames etc.

The easiest way to do the calculation is to flip the question on it's head. What is the probability that we are still not attacking on the 2nd, 3rd, 4th frame? For that to be the case, we must have failed to attack in all the previous frames, and the chance of that is 0.2 each time. Since each trial is independent, we can multiply them together, as follows:

Frame 2: 0.2 * 0.2 = 0.04. 4% chance of not attacking after the second frame

Frame 3: 0.2 * 0.04 = 0.008. A 0.8% chance of not attacking on the third frame or earlier.

Frame 4: 0.2 * 0.008 = 0.0016. Scarcely a 0.1% chance that we are not attacking 4 frames of considering it.


So it's pretty certain we'll attack within the first 3 frames, our code is largely creating variety in behaviour over a range of just 0.3 seconds. Even if we changed the probability to 0.5 we'd still expect the monster to attack quite quickly: 1 / (2^10) is the probability that we wouldn't have attacked after 1 second - which works out at > 0.1%.

Using attack_finished as a cooldown is probably the best way to to long pauses out of your monsters, if you want them to choose between attacking with a missile or closing the distance with the player. 
Yeah 
that makes a whole lot more sense. i confused myself over why the chance to attack would go down over time, which is just stupid because every time we check, we are giving a new chance to attack. 
Quick Question 
I have a feeling I could find this if I dug through the Quake source, but are the lengths of key/value pairs for map entities limited to 16 and 32 chars respectively? If not is there some other limit? Does anyone know.

On top of that, if anyone happens to know the max number of:
entities in a map
faces per brush (guess this is compiler limited)
key/value pairs per entity

I'd love to know them :) 
^^ 
Thanks 
1024 seems quite a lot. I'll just get rid of the limits I put on my map loader.

Texture names do appear to be limited to 16 chars though. 
 
Texture names do appear to be limited to 16 chars though.

15 chars unfortunately, since you need a null terminator. 
 
This is not QuakeC related. The answer is hopefully simple algebra but I am too stupid to figure it out for myself and Google is not helping.

Let's say I have these 2D coordinates:
1) 10;10
2) 54321;12345

and want to fit them into a smaller (let's say 800x800) window. How would I code that? Do I really need to make an affine transformation? If yes, no need to explain the how, I should know that. 
";" Is Not A Name 
frikqcc keeps complaining about ";" not being a name in the following function, but I can't any ;'s being used as names, or any stray ones that might being messing with things. This is just the BackpackTouch func from progs106
<code>
/* PLAYER BACKPACKS */
void() BackpackTouch =
{
local string s;
local float best, old, new;
local entity stemp;
local float acount;

if(other.classname != "player")
return;
if(other.health <= 0)
return;

acount = 0;
sprint(other, "You get ");

if(self.items)
if((other.items & self.items) == 0) {
acount = 1;
sprint(other, "the ");
sprint(other, self.netname);
}

// if the player was using his best weapon, change up to the new one if better
stemp = self;
self = other;
best = W_BestWeapon();
self = stemp;

// change weapons
other.ammo_shells = other.ammo_shells + self.ammo_shells;
other.ammo_nails = other.ammo_nails + self.ammo_nails;
other.ammo_rockets = other.ammo_rockets + self.ammo_rockets;
other.ammo_cells = other.ammo_cells + self.ammo_cells;

new = self.items;
if(!new)
new = other.weapon;
old = other.items;
other.items = other.items | new;

bound_other_ammo();

if(self.ammo_shells) {
if(acount)
sprint(other, ", ");
acount = 1;
s = ftos(self.ammo_shells);
sprint(other, s);
sprint(other, " shells");
}
if(self.ammo_nails) {
if(acount)
sprint(other, ", ");
acount = 1;
s = ftos(self.ammo_nails);
sprint(other, s);
sprint(other, " nails");
}
if(self.ammo_rockets) {
if(acount)
sprint(other, ", ");
acount = 1;
s = ftos(self.ammo_rockets);
sprint(other, s);
sprint(other, " rockets");
}
if(self.ammo_cells) {
if(acount)
sprint(other, ", ");
acount = 1;
s = ftos(self.ammo_cells);
sprint(other, s);
sprint(other, " cells");

sprint(other, "\n");
// backpack touch sound
sound(other, CHAN_ITEM, "weapons/lock4.wav", 1, ATTN_NORM);
stuffcmd(other, "bf\n");

// remove the backpack, change self to the player
remove(self);
self = other;

// change to the weapon
if(!deathmatch)
self.weapon = new;
else
Deathmatch_Weapon(old, new);

W_SetCurrentAmmo();
};</code> 
Deception 
The error message is true but unhelpful. It's trying to use a ; as a name, but what that means is that it's reading a line in a way you didn't intend. Often you get unexpected parsing errors when you leave a function earlier or later than expected. In this case you're missing the closing braces for the self.ammo_cells block, and so it's reading some further code incorrectly.

I know that func_ eats indentation(unless you're really patient with inserting nbsp character entities) so I can't say if missing indentation might have made this harder to spot. But I can recommend editing code in something that can highlight matching braces in some way - I pasted the code into notepad++ to check the matching. I will concede that knowing it could be a mismatched brace based on the error was really key, so it's not all software solutions. 
Hat Tip 
That was it, thanks Preach. In my editor (acme) everything is indented fine, but as you said func_ at them. Wish func_ has support for <code></code> tags. 
Don't Forget To Spellcheck... 
s/at/&e 
 
a preformatted tag would be nice, but that would likely break the forum width?

mind you, the forum could probably get twice as wide without bothering anyone. 
 
No, absolutely not. Apart from the colours and no-clutter, the 72-80 character line length ensures the great readability of func. Forums that spread to full-width (or anything remotely like that) are an abomination.

Use http://www.inside3d.com/pastebin.php , that even gives you syntax highlighting. Also be aware that func has a preview button. ;) 
Yeah 
No offence to Quakeone.com for example, but having like more than 12 words on a line is a bit of a no-no. Just hurts my eyes :) 
Good Point 
 
Ok... 
 
Ropes... 
so i was wondering... how hard would it be to create some kind of dynamic rope thing in QC?

i'm thinking, you would put down a func_rope and then specify the length of the rope. then target at an info_notnull.

for the code, i first thought it would be pretty easy, all you'd have to do is first spawn an entity chain and then set each of the nodes in the chain to obey quake gravity.
then, all you'd need to do is check every frame to make sure the next link hasn't moved out of range and if it has, move it back along a straight vector.

but then i started thinking that you can't just iterate forward through the chain because you would have two anchored positions with only the center moving freely and then my head exploded. :( 
Oh 
and this is the best part: i started trying to code it because i was too lazy to make brushwork wires in my map. �_� 
 
ropes are easy enough, just set up a havok-like physics system and include inverse kinematics, then set up the constraints between your rope links, and mark the two ends as unmoveable. :) 
You Have To Burn The Rope From Both Ends At Once 
With two anchor points, you have the trail of gravity come from both at once. The only tricky situation is in the middle. 
Actually.... 
if all you want is a rope that doesn't collide with anything, including itself... it's doable.

To solve the rope position for a static rope, you just set it up at spawn: guess and then iteratively refine the locations of all entities until it's within a certain tolerance.

If you want it to be dynamic, you don't need iteration, but you give the rope some elasticity and then have it accelerate to the correct position every frame. With the right values, it will look pretty good. Otherwise it will be bouncy and rubbery and go crazy. 
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