P3D v4 Animating Propellers

[Adam_WMidsUK]

Hi All

I'm new to sim aircraft creation... but have spent hours and hours (at least 100!) reading, watching video tutorials and following 3DS Max and P3Dv4 SDK documentation. I have got a complete model, with animated landing gear, fully textured with LM, specular and bump maps. But am stuck with animating propellers at the moment.

I'm modelling a two engine prop for use as AI only, so am not concerned with animating the propellers for viewing from a virtual cockpit. I've searched forums, YouTube and read the SDK documentation and can't find anywhere which clearly explains the principle for animating the propellers.

I understand there are three animations to create which need to use the prop0/1_slow/still/blurred animation tags. I also understand that the propeller modelling will be used at slower speeds, but a blurred texture (I assume assigned to a 2d plane using the Propeller material settings as per the SDK) will be used to represent faster speeds. This I am fine with (assuming it is correct!).

What I can't find anywhere is any description of the technique used to ensure that only the 3d propeller modelling is visible at the slow speeds and the only the 2d texture with alpha for transparency is visible at higher speeds.

Does anybody know the best place to look for guidance on modelling propellers? Or does anybody have the time to write down some pointers for me? Or what search term I need as I'm not finding it from searches so far!

Any guidance is gratefully received!

Kind regards

Adam

 

[ErickC]

You have to assign the appropriate visibility tags as well.

 

[Roy Holmes]

The modeldef.xml file has the visibility of still, slow and blurred props. You need all three modeled.
Basically from zero to 6.25% of max RPM the still version will be visible, above 6.25 and below 12.5 you get the slow and the blurred is visible above 12.5.
Roy

 

[Adam_WMidsUK]

Really appreciate you takiing time to reply guys. I'll take a look at visibility tags in my next session.

Roy - When you say 'all three need to be modelled' do I need three distinct objects in my model to represent the three states? Or is it possible to animate the still state between frames 0-100, and slow between 100-200 both on the 3d modelled propeller and just tag the appropriate frame ranges for P3D? (And then the blurred state on the 2d plane only of course)?

Cheers

Adam

 

[hairyspin]

Adam, you do need a still, a slow and a blurred prop, each animated over the same keyframe range and tagged via the Animation Manager. I recommend 5 keyframes over a full revolution at 0, 90, 180, 270 and 360 degrees rotation for each. Each also has to be tagged with the appropriate visibility tag. Some modellers do without the slow prop, but that's a personal decision.

 

[tgibson]

I create all three props for AI aircraft:

1. Still prop, modeled as a propeller. Used when the engine is stopped.
2. Blurred prop, modeled as a disk with a partially transparent texture applied. Used for the engine when it is at greater than idle conditions.
3. Slow prop. This prop will be used for idle conditions on the ground and in the air. The blurred prop is used, but I cut out wedges of the disk until I have remaining only the number of wedges that the original prop has blades, in the correct radial orientation. I often reduce the transparency a bit to make it a little more opaque.

Hope this helps,

 

[Adam_WMidsUK]

Hi All!

Thanks for the pointers - got me to where I wanted to be! Visibility tags added and three objects for the different states created - It is working in MCX as a test.

Tgibson - Yeah I think I might re-do the Slow prop. At the moment I have still on 1 revolution in 100 frames, slow on 3 revolutions in 100 then a blurred texture on 1 revolution per 100. Blurred looks fine as does still, But I think slow is going to be too slow!

Thanks all - really appreciate it.

Regards

Adam

 

[tgibson]

An oddity with FS animations is that the slow and blurred props use "stroboscopic" animations that you see using a video or film movie camera. You do not see this looking at the plane with your own eyes. But it's been this way since the early days of prop animation in FS, and most people expect it. A few (Jens Kristensen is one) don't like it and make perfectly flat slow and blurred prop textures so there is no apparent movement at all, no matter the FS animation.

As for the speed of this animation, it can be changed with a line in each fltsim section of the aircraft.cfg file, like this:

prop_anim_ratio=0.9

Using a number other than 1.0 keeps the animation from being static at full throttle, etc.

 

[Heretic]

Since I was too lazy to deal with the prop disks, my FSX converted AI models have their props in "slow scan" mode. Not realistic, but it sure does look cool.

 

[kalong]

I have problem with "choopy", still finding way how to make a smooth flow rotation.

 

[tgibson]

Can you have more total keyframes? Never tried it.

 

[Heretic]

Can you have more total keyframes? Never tried it.

Anything supported by the animation length tag in the modeldef entry is possible, as long as you adjust the input variable processing accordingly. If you want, you can have 360 keyframes for a single prop animation.

 

[n4gix]

I have 1000 frames for one aircraft's still props. I needed to have it start very slowly (for 'dry' cranking) then gradually speed up during ignition.

 

[lionheart]

When I animate props, I do it in 90 deg segments, 25 Key Frames (KF's). 0-0, 25KF=90deg, 50KF=90deg (total 180deg), 75KF=90deg (270deg), 100KF=90deg (360deg).

Just turn it 90 deg, click the Key Frame Rotation button. No movement at zero point. Just 25, 50, 75, and 100 KF points.

1,000 key frames....!! Dang... That is some intense key frames. I'll bet its very smooth. Kalong, that is probably what you need.

 

[kalong]

I use 100 keyframe, use fmod(); in C++ to drive the prop and disk rotation. rotation value stop at 80 and steady as long as engine running
it smooth at start, choppy issue came when it at stable value ( 80 );

from default prop_anim it have:
<Scale>15.92</Scale>
can someone give a clear view about that <Scale>?

 

[tgibson]

From Bill's book of modeldef gospel:

To convert a simvar to keyframes: simvar * scale + bias = keyframes

get the details from:

http://www.fsdeveloper.com/forum/threads/timed-visibility-parts-yes-no.23316/#post-155674

http://www.fsdeveloper.com/forum/threads/rmi-needles-3d.20285/page-2#post-214379

http://www.fsdeveloper.com/forum/threads/kohlsman-scale-animation-code.440861/#post-779740

http://www.fsdeveloper.com/forum/threads/engine-gauge-needle-animation.440066/#post-771964

http://www.fsdeveloper.com/forum/threads/vc-elevator-trimtab-wheel.429841/#post-669034

http://www.fsdeveloper.com/forum/threads/fsx-xml-help.62680/page-2#post-210449

Hope this helps,

 

[Heretic]

I have 1000 frames for one aircraft's still props. I needed to have it start very slowly (for 'dry' cranking) then gradually speed up during ignition.

Interesting apporach.

I've created a custom animation using an L: var to control rotation for motoring the engine with a starter. Upon actual ignition, the default RPM variable takes over.

 

[n4gix]

Interesting apporach.

I've created a custom animation using an L: var to control rotation for motoring the engine with a starter. Upon actual ignition, the default RPM variable takes over.

Being concious of poly counts, I opted to use the first 100 frames for the motoring (dry cranking), and frames 101 to 1000 for the ignition animation. It only is seen for about 4 seconds before the prop0_slow animation takes over, but has the effect of spining faster and faster so the abrupt transition is minimized. This method only require one prop0_still object.