[Software] LUA - Animation for LDcad

[kaanguyr]

Hi there.

I'm a one-year LDcad user and now a newbie with LUA and animation. I use LDcad v1.5 on Ubuntu 16.4 LTS. I have reproduced the example in the Roland Merkel Youtube, simplified it and, after some time to struggle, I have an error "Active refline link needed" in the line reading ax1:setOri(ori). I consulted the Message error script console ldcad1.5 topic in the LDraw forum, but this is not the case, and there is no information about LUA in the Internet.  I send the animation2.mpd and the .lua files for examination. All seems to be in order, but nothing happens.

Any suggestion? Thanks in advance for your help.

=========== animation2.mpd ===========================

0 FILE main.ldr
0 Author: Conrad G.-Anleo
0 !LDCAD SCRIPT [source=animation2.lua]
1 16 0 0 0 1 0 0 0 1 0 0 0 1 axel1.ldr
0 FILE axel1.ldr
0 Author: Conrad G.-Anleo
1 7 0 0 0 0 1 0 0 0 -1 -1 0 0 32073.dat
1 14 0 0 0 1 0 0 0 1 0 0 0 1 32072.dat

========== animation2.lua =================

--[[
     animation2.lua
     (c) Conrad G.-Anleo
]]

function register()

  local ani=ldc.animation('demo')
  ani:setLength(20)
  ani:setEvent('frame', 'onFrame')
end

function onFrame()

  local ani=ldc.animation('demo')
  local mainSf=ldc.subfile()
  local ori=ldc.matrix()
  local angle=-4*360*ani:getFrameTime()/ani:getLength()

  local ax1=mainSf:getRef('axle1')
  ori:setRotate(angle, 1, 0, 0)
  ax1:setOri(ori)
end

register()

============= END ==============================

 

[roland]

The setOri fails because the ax1 variable isn't set as 'axle1' is not found.

 

You must use

local ax1=mainSf:getRef('axel1.ldr')

Also to rotate the gear axle you'll need to rotate around the z axis: setRotate(angle, 0, 0, 1)

Hope this gets you back on track :)

 

[kaanguyr]

Ooooops!

I feel so stupid! So many times I reread the script without realizing the typing error: 'axel1' instead of 'axle1'. I corrected the mistyping and here you are: Same Error. There must be a 'newbie' error, I know, but I'm lost. That's the reason I reduced the example to your variables set, and to only one axe: simplicity.

Don't mind the matrix. I forget always which set of zeroes goes with a specific axle. I always solve it by 'try & error' (an a reread of your notes about LDCad)

Thanks for your patience and quick answer,

The script is unchanged, The modet now is:

0 FILE main.ldr
0 Author: Conrad G.-Anleo
0 !LDCAD SCRIPT [source=animation2.lua]
1 16 0 0 0 1 0 0 0 1 0 0 0 1 axle1.ldr
0 FILE axle1.ldr
0 Author: Conrad G.-Anleo
1 7 0 0 0 0 1 0 0 0 -1 -1 0 0 32073.dat
1 14 0 0 0 1 0 0 0 1 0 0 0 1 32072.dat

 

 

 

 

[roland]

42 minutes ago, kaanguyr said:

 typing error: 'axel1' instead of 'axle1'. I corrected the mistyping and here you are: Same Error. There must be a 'newbie' error, I know, but I'm lost.

Don't forget to include '.ldr' in the getRef line.

The getRef function needs the literal name of the (Nth) used part you want to link to, the easiest way to get that name is by copying it from the properties window (like i do in the second animation tutorial youtube clip.)

If that link fails (part not found) it will cause the mentioned error on the first usage attempt (setOri in this case).

Edited November 14, 2016 by roland

[kaanguyr]

Yeah!!!,

You got it!. It was the.ldr in the GetRef line. I presumed it was the block name, not the filename. Thank you. I owe you a postcard.

[kaanguyr]

Hello Roland. It's me again.

As you can see I'm learning LUA applied to LDCad in an intensive manner. It's something like "LUA - From Dummy to Expert in One Week"

Now, there is a new question: What Does the following error message mean? Playback is to slow for 25 fps at an avg frame time of 45.77ms. I got it just viewing one of your examples without changing anything, [5580.mpd and the corresponding .lua] and others. Playing a little with my files I get the same error (time (ms) changes, offcourse), specially with more "complex" models.  i.e.: Nothing to note with very simple models (a few parts), but error with the 42039.mpd trying to open the doors or the rear.

I've read all the documentation before writing this post, I promise.

Thanks to you in advance, as usual.

[Philo]

I can answer on this one... this means that your model is too complex and/or your computer hardware is not powerful enough to provide real time rendering at this frame rate. You'll have to lower required frame rate, either in default settings (prefs->animation), or using setFPS meta, or using the animation panel. Note that you can still generate a high fps video (but not real time) using the export function (view ->editing views -> openGL animation export)

[kaanguyr]

OK. Thanks, Philo. I'll put a new PC on my Christmas gift list.

[roland]

Slow playback is usually because of the rendering being to slow as the lua script execution itself is rarely above 1ms.

Also I did make some optimizations in 1.6 regarding the fps timing as 1.5 sometimes has false timings on that front.

Has the 5580 model a decent render time (e.g. <20ms reported in left bottom corner) during editing?