Side Position Detection

11-04-2008, 04:30 PM

How would I be able to detect a unit within a 300 distance from an angle to another angle?
^ 45degrees
| /
| / x
| /
|/
| X
|\
| \ x
| \
| \
v 135degrees
For all the side detection I found on this site, are all "If attacked on the side then reduce/increase damage."(backstab/reduce side damage) None of them really detect if a unit were to enter a range of 300, order another unit to attack them (exp : turret of a ship, just wouldn't make sense to attack in a 360 degrees)

11-04-2008, 06:16 PM	#2
Vexorian	Two angles' "distance" cannot be bigger than 180 degrees, man Could you explain better what you want? For example try giving us sample input data and the result you want.

11-04-2008, 06:35 PM	#3
Raydude	Eh I probably should've explained more, sorry. I drew a little weird diagram, the angle I want isn't 180, that'd be weird, it's from Current facing angle + 45 to Current facing angle + 135, the side of the unit. I drew that with slashes, the straight line was just indicating the unit

11-04-2008, 08:54 PM

tamisrah

-First you have to detect that a unit comes in range of your "turret"
-Then compare the angle between the "turret" and the triggering unit to the "turret"s facing angle
-If the difference is lower than your limit (45°) then all thats left is check whether the triggering unit is in front or behind your tower (see backstab detection)

The reason for the additional check is that angleBetweenPoints returns an angle between 0 and 180° as Vexorian already mentioned.

11-04-2008, 11:48 PM

Raydude

This is what I got so far to detect if Target[0] is at the side, but I have questions. Whenever I use that custom script, it always asks for a variable name, didn't I alrdy put it in, also when using the real, what numbers do I use to be "less than or equal to" and "greater than or equal to" so it'd be the sides, not tbe back of the unit?

Trigger:

Events

Time - Every 0.25 seconds of game time

Conditions

Actions

Set Target[0] = (Random unit from (Units within 300.00 of (Position of Carrier 0000 <gen>) matching ((((Matching unit) is alive) Equal to True) and ((Owner of (Matching unit)) Not equal to Player 1 (Red)))))

Custom script: set Real = Backstab_GetAngleDifference(GetUnitFacing(Carrier_0000()), GetUnitFacing(Target[0]()))

If (All Conditions are True) then do (Then Actions) else do (Else Actions)

If - Conditions

Real Less than or equal to 60.00

Then - Actions

Floating Text - Create floating text that reads Works at (Position of Carrier 0000 <gen>) with Z offset 0.00, using font size 10.00, color (100.00%, 100.00%, 100.00%), and 0.00% transparency

Floating Text - Change the lifespan of (Last created floating text) to 0.20 seconds

Else - Actions

P.S. I did put the math codes in the map

Hidden information:

11-05-2008, 03:23 PM

tamisrah

EDIT: Not exactly what I thought first but here you are:

Trigger:

ANGLE TEST

Actions

Set a1 = (Angle from p1 to p2)

Set a2 = (Facing of Akolyt 0000 <gen>)

If (All Conditions are True) then do (Then Actions) else do (Else Actions)

If - Condition

a2 Greater Than 180.00

Then - Actions

Set a2 = (a2 - 360.00)

Else - Actions

Custom script: set udg_a1 = GetAngleDifference(udg_a1,udg_a2)

If (All Conditions are True) then do (Then Actions) else do (Else Actions)

If - Condition

a1 Less Than Or Equal 45.00

Then - Actions

<<Put your Actions here>>

Else - Actions

11-06-2008, 12:27 AM	#7
Anitarf	Try to use [jass] tags for your Jass code. I think you need to explain what you need this for.

11-06-2008, 08:40 PM	#8
Raydude	well, I'm trying to make a large ship with turrets/cannons that only shoots at units at port or portside that enter within 300 range and i can't get the measurements right

11-07-2008, 12:50 AM

PurplePoot

Try using the following for your angle measurement script: it's roughly 3 times faster than your function, though this is admittedly a pretty lame benchmark as I did it by freezing my game and counting (it ended up 2 for mine, 7 for yours, for several hundred thousand executions).

Acos(Cos(A-B)) where A, B, and the answer are all in radians.

So what you would do is detect:

JASS:

local unit u = //battleship
local unit u2 = //considered
local real a = Acos(Cos(Atan2(GetUnitY(u2)-GetUnitY(u),GetUnitX(u2)-GetUnitX(u)) - GetUnitFacing(u)*bj_DEGTORAD))
if a > bj_PI/4 and a < 3*bj_PI/4 then
    //go

If you want to go pure GUI,

Trigger:

Actions

-------- this leaks, too lazy to write in the fixes, you should know them --------

Set Angle = Acos(Cos(((Angle between (Position of (Battleship)) and (Position of (Considered))) - (Facing of (Battleship)))))

If (All Conditions are True) Then do (Then actions) Else do (Else actions)

If - Conditions

Angle > 45.00 Equal to True

Angle < 135.00 Equal to True

Then - Actions

-------- go nuts --------

11-07-2008, 03:14 PM	#10
tamisrah	@PurplePoot: You're version is only about twice as fast to my measurements but actually I'd like to ask you what your one actually does. What is the Acos(cos()) there for? In my opinion it should just nullify eachother but if I remove it the function returns false angles.

11-07-2008, 05:57 PM	#11
Anitarf	That's a common mistake. You forget that the Acos function only returns values between 0 and pi, while the subtration of two angles between 0 and 2pi could generate angles between -2pi and 2*pi. As a result, PurplePoot's function does not distinguish between targets on the left and targets on the right; he should be using Asin(Sin(...) instead.

11-07-2008, 10:57 PM

#12

Raydude

Ah, thanks you all! It works and only targets the left side, if I changed the angle check to >225 and < 315 and it'll be right side. Now I'ma just change the unit that's acting as the cannon to stop bumping into the main unit. Btw, it works, but I have a feeling that there's a much easier check...maybe.

Untitled Trigger 003:

Events

Time - Every 0.50 seconds of game time

Conditions

Actions

Unit - Move CarrierShoot instantly to (Position of Carrier 0000 <gen>)

Set TargetUnit = NoTarget

Set TargetUnit = (Random unit from (Units within 300.00 of (Position of Carrier 0000 <gen>) matching ((((Matching unit) is alive) Equal to True) and (((Matching unit) belongs to an enemy of Player 1 (Red)) Equal to True))))

Game - Display to (All players) for 1.00 seconds the text: (String((Unit-type of TargetUnit)))

If (All Conditions are True) then do (Then Actions) else do (Else Actions)

If - Conditions

(TargetUnit is alive) Equal to True

(Owner of TargetUnit) Not equal to Player 1 (Red)

Then - Actions

Trigger - Run Untitled Trigger 001 <gen> (ignoring conditions)

Else - Actions

Untitled Trigger 001:

Events

Conditions

Actions

Set CarrierSpot = (Position of Carrier 0000 <gen>)

Set TargetSpot = (Position of TargetUnit)

Set Angle = (Asin((Sin(((Angle from CarrierSpot to TargetSpot) - (Facing of Carrier 0000 <gen>))))))

If (All Conditions are True) then do (Then Actions) else do (Else Actions)

If - Conditions

(Angle Greater than or equal to 45.00) and (Angle Less than or equal to 135.00)

Then - Actions

Unit - Order CarrierShoot to Attack TargetUnit

Else - Actions

Do nothing

Custom script: call RemoveLocation (udg_CarrierSpot)

Custom script: call RemoveLocation (udg_TargetSpot)

11-08-2008, 12:01 AM

#13

PurplePoot

@Anitarf, I would personally just have another check completely for the right (especially since I assume it's a different cannon with a different cooldown). Perhaps a bad assumption, but meh.

EDIT: Ah, I see what you're getting it... Trust me to screw something like that up when being too lazy to just measure from facing + pi/2.

--

@tamisrah, in GUI or Jass? GUI hardly counts due to all the BJs.

11-08-2008, 11:04 AM	#14
tamisrah	JASS with StopWatch natives, but I'm not totally confident with how to ensure precise measurements (just took the example and inserted both codes and measured the time to execute each one a thousand times)