Here's the run down:
- Brake Cylinder Animation: Use an animation matrix with a name that begins with ORTSBRAKECYLINDER (if you need multiple animated brake cylinders, names like ORTSBRAKECYLINDER1, ORTSBRAKECYLINDER2, etc will work, this is true of all the shape animations)
- Handbrake Wheel Animation: Animation matrix name beginning with ORTSHANDBRAKE
- Brake Rigging and Brake Shoe Animation: Animation matrix name beginning with ORTSBRAKERIGGING
Use ORTSBRAKECYLINDER for any brake equipment that ONLY moves when the brake cylinder moves and does NOT move when the handbrake is applied (typically, this is the brake cylinder itself, but sometimes the brake cylinder is actuated by the handbrake!)
Conversely, use ORTSHANDBRAKE for any brake equipment that ONLY moves when the handbrake is applied but does NOT move when the brake cylinder moves (typically, this would be the handbrake wheel because the handbrake wheel does not spin when the train brakes apply...looking at you, TSW).
Finally, ORTSBRAKERIGGING is for all the other brake equipment-the things that can be moved by BOTH a handbrake application and automatic brake application (typically, this is the brake levers and brake shoes, but sometimes the brake cylinders fit into this category).
On equipment with disc brakes, you can use these animations to animate brake applied/released indicators too!
There are a few things to consider setting up these animations. For the animations driven by brake cylinder travel (that is, ORTSBRAKECYLINDER and ORTSBRAKERIGGING), the selected animation frame will depend on the simulated brake cylinder travel. This means that you really should use the advanced brake cylinder parameters ORTSBrakeCylinderDiameter and ORTSBrakeCylinderPistonTravel to give reasonable animation in response to the simulation. You can use the animations without the advanced brake cylinder simulation but it may not look as convincing. Now, the values assigned to the animation keys are vital, as the animation key itself represents the amount of brake cylinder travel. So a key value of "8" doesn't mean 8 seconds like in other animations, it means a brake cylinder travel of "8" (the value is normalized, so 8 doesn't actually have units, it isn't a number measured in inches or meters).
The animation values to consider are:
- 0 - brakes fully released, no brake cylinder motion
- 8 - the brakes are applied enough for all slack to be removed from the brake rigging; any brake shoe animation should set the brake shoes to touch the friction surface at the 8 keyframe (after this, the brake shoes should not move, but other components can still move due to flexibility in the rods and levers)
- 10 - the brake cylinder pressure is 50 psi/3.5 bar, this animation should represent the 'normal' amount of brake cylinder travel; note that the animation will run up to the 10 keyframe over 1 second whenever the brakes are applied on trains without advanced brake cylinder simulation (also, for ORTSBRAKERIGGING objects, the handbrake will set the animation to the 10 keyframe)
- 16 - the maximum possible brake cylinder travel allowed in the simulation, occurs around 200 psi brake cylinder pressure (ie: shouldn't ever happen); if your animation looks good up to the 16 keyframe you are good to go for everything the sim throws at your train car
Note that these rules do NOT apply to the ORTSHANDBRAKE animations. Those behave like a normal two-state animation where the keyframes represent time.
Also, there is no need to make an animation that covers the entire range of motion of the brake equipment. If you want something that just shows the brake cylinder extending enough to take up slack and nothing more, then simply don't define any keyframes greater than 8. If you don't think you need 8 individual animation frames, simply skip the keyframes that seem unneeded. OR is smart enough to smoothly animate in between missing keyframes, and will stop the animation when it reaches its maximum value.