Rtm (Animation) File Format

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Binary Format

For binary rtm's see Rtm Binarised File Format

Conventions

see Generic FileFormat Data Types

Animations

• RTM files are applied to any P3d that has a 'skeleton'. Not ALL p3d's have them.

• The appropriately termed 'skeleton' consists of 'bones' such as heads, arms, legs, feet, doors.

• The skeleton as such, is not used by an rtm file. Part, or all, of the bones of the skeleton are.

• An rtm frame consists of a collection of bones. Each frame contains identical bones but each of those bones are individually displayed at differing orientations.
• The same rtm file can be applied to different p3d's on the assumption of course that the bone names in each of those p3d's are identical. This would be reasonable for a collection of soldiers eg.

And so:

RtmFile

RtmFile 
{
 char       Signature[8];          // "RTM_0101" note. This is not asciiz
 XYZTriplet Vertex;                // Total Moving XZY. At 0,0,0 'soldier' runs in same spot.
 ulong      nFrames;               // Self Explanatory?
 ulong      nBones;                //
 BoneName   BoneNames[nBones];     // 
 RtmFrame   Frames[nFrames];
};

The number of frames (and bones in each frame) extend to the end of file. There is no checksum or end of file signature.

BoneName

char BoneName[32];   //fixed 32 byte record for each bone. NOT asciiz

RtmFrame

RtmFrame
(
  float          FrameTime; // Values 0.0 to 1.0
  BoneTransform  Bone[nBones];
};

Frametime

Represents a percentage of 'time' relative to the total time taken to display all frames. The overall time is not indicated in the rtm. External sources cause the 'frames' to move fast, or slow, or whatever.

This is one of those parameters that are easy to understand, and difficult to explain.

The value represents percentage of the expiry time for the entire frameset.

Given ten frames, all of which you want displayed for the same amount of time. the frametime value would progress, 0,0.1,0.2,0.3 etc, not, as would be intuitive, 0.1,0.1,0.1,0.1.........

BoneTransform

BoneTransform
{
  BoneName   BoneName;      //Identical to that found in header above, and in same relative order
  Transform  Transform;     //The orientation of the model.
};

The exact same number of bonesis specified inside every Frame, as per the initial list in exactly the same order. In effect, naming again, in every component, in every frame is redundant. This has since been corrected in the binarised rtm version.

Transform

Transform
{
  XYZTriplet Triplet[4]; // eg float[4][3]
};

This is the transform matrix used directly by Microsoft DirectX engines.

In fact, the 'correct' matrix is actually 4 x 4, but the last column always represents 0,0,0,1 thus

M11,M12 M13 (0.0)
M21,M22,M23 (0.0)
M31,M32,M33 (0.0)
M41,M42,M43 (1.0)

and so is never stored.

similar Transform matrices are used for WRP and P3d files as well.

The last row (M41...) happens to be the position of the object X Z Y co-ordinates, and is often referred to separately.

For further information visit

Microsoft Transforms (Direct3D 9)

Examples

Bonenames apply to p3d models that have skeleton structure. This, chiefly, to class man objects (soldiers, civilians, etc). They are internal to the engines.

There are 25 bone names in ofp, and 65 in arma1.

Ofp

           hlava(Head)
           krk(Neck)
           zebra(Spine) //ribs
           hrudnik(Spine1 2 or 3) //chest
            bricho(Pelvis) //abdomen
lrameno(LeftShoulder) prameno(RightShoulder)
lbiceps(LeftArm)      pbiceps(RightArm)
lloket(LeftForeArm)   ploket(RightForeArm)
lruka(LeftHand)       pruka(RightHand) //right fist
lprsty(LeftHand)      pprsty(RightHand) //left right fingers
lstehno(LeftUpLeg)    pstehno(RightUpLeg)
lholen(LeftLeg)       pholen(RightLeg) // lower legs
lchodidlo(LeftFoot)   pchodidlo(RightFoot)
lzadek                pzadek          // right buttock
           zbran(weapon)   //primary weapon proxy
           roura(launcher) //secondary weapon proxy

Arma

          Head
          Neck
          Neck1
          Spine
          Spine1
          Spine2
          Spine3
          Pelvis
LeftShoulder  RightShoulder
LeftArm       RightArm
LeftArmRoll   RightArmRoll
LeftForeArm   RightForeArm
LeftForeArmRoll RightForeArmRoll
LeftHand      RightHand
LeftHandThumb1  RightHandThumb1
LeftHandThumb2  RightHandThumb2
LeftHandThumb3  RightHandThumb3
LeftHandIndex1  RightHandIndex1
LeftHandIndex2  RightHandIndex2
LeftHandIndex3  RightHandIndex3
LeftHandMiddle1 RightHandMiddle1
LeftHandMiddle2 RightHandMiddle2
LeftHandMiddle3 RightHandMiddle3
LeftHandRing    RightHandRing
LeftHandRing1   RightHandRing1
LeftHandRing2   RightHandRing2
LeftHandRing3   RightHandRing3
LeftHandPinky1  RightHandPinky1
LeftHandPinky2  RightHandPinky2
LeftHandPinky3  RightHandPinky3
LeftUpLeg              RightUpLeg
LeftUpLegRoll          RightUpLegRoll 
LeftLeg                RightLeg
LeftLegRoll            RightLegRoll
LeftFoot(pchodidlo)    RightFoot
LeftToeBase            RightToeBase
           weapon
           launcher
           camera