Ship Shaking

I think they were just lazy/didn’t have the time to fix it. I seriously see no advantage whatsoever, but I can see they haven’t fixed it because the systems they have didn’t get to a point where the shaking was really noticeable. It also goes in line with the large amount of stuff that’s half-done in the game.

You may find that it has to do with the integers Freelancer uses for the system. As you know it "plots"position coords.

There are two issues here and maybe this is what causes the shaking -
1. is the physical game default scale - which is 100kx100k
2. is the repositioning to check the players position with the navmap - which you scale to get the system larger

The engine is built on plotting to a standard size and therefore the “plotting” of the player ship will become more “inaccurate” the larger the system is. This is a common issue with largescale terrain in game engines which are not made for it.

My suggestion to fix this once and for all is to find the entry in the exe and increase the “standard” size (i.e. Li01 - doesnt have a navmapscale, its default), then see if the navmapscale in the universe.ini will work better.

The idea being that if the default size is only 100kx100k (New York, no nav map scale), And you set it to 100,000k or a similar multiple, the engine might cope with this better if its already the defult size.
either way, I do believe that the issue is the game trying to match your position in the actual game itself and the navmap, which are both updated at the same time.

**The error is actually due to matrix destabilization. The matrix for the camera is based off of the coordinates of the ship. Once the numbers get large the floating point errors start getting quite large. There is a fix but it would require an addition to the exe to fix it (w0dk4, a hook maybe?)

The quaternion matrix needs to be normalized right after its created and before it is transformed with the position vector. It is a single DX command but without the source I am unable to fix it.**

@Lancer:

**The error is actually due to matrix destabilization. The matrix for the camera is based off of the coordinates of the ship. Once the numbers get large the floating point errors start getting quite large. There is a fix but it would require an addition to the exe to fix it (w0dk4, a hook maybe?)

The quaternion matrix needs to be normalized right after its created and before it is transformed with the position vector. It is a single DX command but without the source I am unable to fix it.**

youll forever been an enourmous source of knowledge mate lol

@Lancer:

**The error is actually due to matrix destabilization. The matrix for the camera is based off of the coordinates of the ship. Once the numbers get large the floating point errors start getting quite large. There is a fix but it would require an addition to the exe to fix it (w0dk4, a hook maybe?)

The quaternion matrix needs to be normalized right after its created and before it is transformed with the position vector. It is a single DX command but without the source I am unable to fix it.**

As I understand it, the floating point errors increase simply because of the high float numbers, losing precision. How does your proposal help solve that?
I dont know a lot about 3D DirectX math stuff so please explain a little more

**Well, I ran into this exact same problem writing my game engine. It took some time to track it down but it turned out that one of the quaternion routines in DX requires a normalized matrix. Unfortunately I don’t know where it is stored in FL, I ran across it a couple of years ago.

Basically the matrix needs to be normalized (converted to a 0.0 to 1.0 range) after this command D3DXQuaternionRotationYawPitchRoll and before this command D3DXMatrixAffineTransformation. The command that needs to be called is D3DXQuaternionNormalize and it needs to be the output from D3DXQuaternionRotationYawPitchRoll.

Sorry, I said position earlier, I was at work and didn’t have the code to look at, still part of the position transform is done by D3DXMatrixAffineTransformation. .

BTW, it’s actually the camera shaking, not the ship.

Edit - forgot to mention this, but the fix can also be applied in the view matrix calculation routine…**

So, I have been doing some research on this and found quite a few things, sadly my conclusion is bad:
Not fixable.

I was right earlier in this thread, floating points simply lose precision and at values of like 5000k, this precision error is already 0.5m. Thats why your cockpit jumps all over your screen that far out in a system.

@LS: FL doesnt really use D3DX functions as far as Im aware, they have their own math library which can be found in x86math.dll.

I’ll look thru my math code and see if I ever wrote a matrix normalization routine.

i smell a hook plugin ^^

I’m crossing my little fingers and toes that it does mean that

@Sushi:

I’m crossing my little fingers and toes that it does mean that

im hoping so bad ill cross your fingers and toes FOR you ^^

edit cant believe i spelt toes as “tows” rofl

There is no real way to fix this. The important thing to understand here is that Freelancer uses floating points (and I think, D3D8 also only supports floating points for camera stuff, but I may be terribly wrong there) for everything related to space positions and the camera.
When you are at 1000k and 1.0 = 1m, you have a precision of around 6cm.

Now imagine your ship standing at position 0, 1000000.03, 0
Since floating points cannot hold 1000000.03, but only 1000000.0 and 1000000.063, your ship and/or the camera may jump 6cm all the time. You see your ship shaking.
Also, what is important to understand: At those precision errors you can no longer fly in a straight line, your ship will shake when flying (or lets say, your ship will fly in zig-zag-pattern). This is especially visible at extreme distances, like 10000k, if you would login with 2 chars and would spectate the other player flying around.

This happens also to sur files, I’ve noticed that my station at 140000, 105000, 120000 has nearly no collision detection, so i moved the station to 100000, 70000, 95000 and the collision detection is back as it should be.

Greetz
Mind

Note: Its a modul station made of 12 parts + the dock.

Hmm, that’s interesting. We haven’t noticed this effect at FWs, and we have stations 500km from the centre.

@Sushi:

Hmm, that’s interesting. We haven’t noticed this effect at FWs, and we have stations 500km from the centre.

Can we have a look at your constants.ini Sushi please?

[Constants]
COLLISION_DAMAGE_FACTOR = 2
MUSIC_CROSS_FADE_DELAY = 10.000000
MUZZLE_CONE_ANGLE = 25 ;Cannot be zero
PLAYER_COLLISION_GROUP_HIT_PTS_SCALE = 1
PLAYER_ATTACHED_EQUIP_HIT_PTS_SCALE = 1
MAX_PLAYER_AMMO = 1000000000

[EngineEquipConsts]
CRUISE_DISRUPT_TIME = 1
MAX_DELTA_FX_THROTTLE = 0.250000
THROTTLE_STEADY_TIME = 0.500000
THROTTLE_ATTEN_MOD_RANGE = 8.000000
DELTA_THROTTLE_ATTEN_MOD_CHANGING = 8.000000
DELTA_THROTTLE_ATTEN_MOD_STEADY = -1.000000
CRUISE_STEADY_TIME = 10.0;0.100000
DELTA_CRUISE_ATTEN_MOD_STEADY = -5;-1.000000
CRUISE_ATTEN_MOD_RANGE = 8.000000
CRUISING_SPEED = 5000		;10000
CRUISE_ACCEL_TIME = 5		;0.5
CRUISE_DRAG = 85		;250

[ShieldEquipConsts]
HULL_DAMAGE_FACTOR = 1.0

[PhySysConsts]
MATERIAL_FRICTION = 0.001;0.100000
MATERIAL_ELASTICITY = 0.2;0.500000
DEFAULT_LINEAR_DAMPING = 0.500000
DEFAULT_ANGULAR_DAMPING = 0.200000, 0.200000, 0.200000
ANOM_LIMITS_MAX_VELOCITY = 1000000
ANOM_LIMITS_MAX_ANGULAR_VELOCITY_PER_PSI = 0.04
;RMGR_LOOK_AHEAD_TIME_WORLD = 0	;no idea what I'm doing here
;RMGR_LOOK_AHEAD_TIME_INTRA = 0

[CommConsts]
COMM_PLAYER_FAR_DIST = 6000.000000
COMM_PLAYER_FAR_DIST_ATTEN = 0.000000
CHATTER_MAX_DIST = 100000;3500.000000
CHATTER_MAX_DIST_ATTEN = -8;-16.000000
CHATTER_START_ATTEN = -2.000000
COMM_CONFLICT_PRIORITY_CUTOFF = -10;-3
WALLA_MAX_DIST = 100000;3500.000000
WALLA_MAX_DIST_ATTEN = -8;-24.000000
WALLA_START_ATTEN = -2;-8.000000
WALLA_PRIORITY_CUTOFF = -10;-3

[AsteroidConsts]
MAX_ASTEROID_LOOT_DAMAGE = 20000.000000
MAX_LOOT_PER_ASTEROID = 3

Well, I stand corrected. The base collision works about 70% of the time at this distance from the centre. Very interesting. I’ll have to get my guys on it to see what’s going on.

What’s even stranger is that collision detection works fine on the ships at this distance.