LDCad 1.4 Beta 2 (win+linux)

[Roland Melkert]

Hi all,

I just released the second beta of LDCad 1.4

It has a boatload of bug fixes and two new major features, namely OpenGL export and 'triangle angle' selection information the later helps you create something like this:

   

See also this video clip

The first let you export the current editor view (without GUI items) into any size your VGA card supports. For example here's an exported snapshot of the new 8071 example model.

   


8071 includes an advanced animation script example which makes it's mechanics come to live. You can view the exported version of it on youtube. And I also made a second clip showcasing some of the internals.

As animation might be a difficult thing to get started with I also made a two part tutorial video on making an animation from scratch.

Part 1 The model
and
Part 2 The script

Like always you'll find the latest LDCad version at

www.melkert.net/LDCad

The next version will probably be the definitive 1.4 version without any major features as I'm taking a little break from working on LDCad for the next couple of weeks.

Have fun.

[Philippe Hurbain]

Great work! I tried the triangle solver, it works fine. Two questions:
- Your video shows sub bins in Technic bin, I don't seem to find that here?!
- How do I get parts snapping as described here http://forums.ldraw.org/showthread.php?t...6#pid11436 ? Or is this feature not ready for showtime yet?

[Roland Melkert]

Thanks,

Those technic groups are part of the 'sorted' (sorted by function) bin tree branch, accessible through the very first icon (little groups of parts picture) in the root group.

Part snapping is available since the 1.3 version, although it's more a guidance tool not full blown collision detecting etc. But it works quite well when used in combination with the relative grid.

You can enabled/disable it from the compass (GS/PS at the bottom) at any time or by using shift+p.

Do note not all parts have snapping info yet, currently I'm working towards having info for all parts in the sorted branch of the bin which is almost done having only a couple of subgroups remaining.

[Philippe Hurbain]

Those technic groups are part of the 'sorted' (sorted by function) bin tree branch, accessible through the very first icon (little groups of parts picture) in the root group.

OK, clearly I need new glasses - sorry!

You can enabled/disable it from the compass (GS/PS at the bottom) at any time or by using shift+p.

I missed that too... but the keyboard shortcut is not in the quick manual.

[Roland Melkert]

Yes the quick manual is a bit outdated on that front

I'll add a new shortkey table page to the site soon, I will also rewrite the basic usage (aka quickmanual) at some point in the near future, probably in union with one or more video clips and pictures.

[Merlijn Wissink]

Looks very nice!
Although, I've barely used LDCad, but I'd like to try it out. Is there maybe a more extensive manual somewhere than the quick guide on your website? I haven't read it yet, it's probably very useful, but I'm just wondering

I also have a two questions:
1- is there any way to resize the brick-selection images? I find them a little too big. Not that too big, but a little smaller would be much appreciated.
2- is there a way to view the steps and bricks in a list? Something like in MLCad or the Instructions Miner in SR3D Builder?

[Roland Melkert]

The brick sizes in the bin are determined by the current bin width and the current number of grid cell columns. 2 columns is the default but you can increase it by pressing '+' while the mouse is inside the part bin.

Used bricks in the current building step can be inspected/viewed by navigating to the special step content group in the part bin. Reachable from the root group by choosing the sessions group (icon with 'mpd' text in it), followed by going into the last group inside the sessions group (the one with '4' and a couple of beige bricks on it's icon).

That group will always show the current step's bricks in their used color and counts. If you need it often just point one of the last bin views (e.g. 6) to it and use the other ones for normal part navigating.

As for an extended manual, I'm afraid the quick manual is currently the only text available. I started writing a new (more extensive) one though.

In the meantime you could probably pick up the basic way of working from the more recent clips I made, I try to minimize keyboard usage in those.

[Jason Smith]

Hi Roland, thanks for the animation videos, I'm currently building something that I hope to animate at some point.

A couple requests or ideas if I may:

When hovering over the part area tabs (1-6), would it be possible for the text dialog to change showing what that tab has been filtered to? For example when working with technic parts I like to keep axles, beams, pins etc in the different tabs for quick reference. Except being old I forget which ones they are in. So if I hover over the tabs and if the text could change to say "Technic" with "Beam" or "Pin" that would be handy.



Also, is it possible to change the overall GUI theme of the program and it's areas. Being in Linux I like to use the darker "Pro" style look.

[Roland Melkert]

You mean display the filter text of the other view in the current view's filter text area (in green) just like the bin group caption does?

If so I like that, and it's a small change so I will add it to the next version. Thanks for the idea.

As for the colors, you are the second person in as many days who thinks the theme is to bright. 1.0 and 1.1 used a more gray theme but people were complaining about that too

Therefore the current theme is somewhat taken from the official LEGO building booklets, but if you want you can change pretty much any color as the theme colors are read from the GUI/default/main.gui file. I think if you change all the 'BG' items in that file to something dark you basically get what your preview shows.

But be aware a future update will overwrite your changes, unless you copy the whole default folder and change the 'guiTemplate' section in the main.cfg file accordingly.

[Jason Smith]

Yep that's exactly what I meant, you got it. Thank you so much for adding it.

I know it's a tough thing coming up with pgm colors so they don't interfere with part colors etc. I'll play around with a few options and maybe we can share them or keep them someplace.

[Jason Smith]

Here's a copy of the main.gui file that I quickly played with to match the theme of my Ubuntu PC. I find due to the darker shades it's a bit easier on my tired eyes after a while as well. It looks like the image below if anyone would like to try it out. So far I can't find any visual issues.

[Merlijn Wissink]

Ok, I've played a bit with LDCad and I have to say I quite like it and it looks very promising.
A few things I've found a bit annoying so far (and remember, I've only used it for about an hour now, so some of these things are just annoying because I'm new to it):
- I'd like to have a base/floor grid. I quite like the grid that moves, but a floor that would stay in place whatever camera position I'm at would be very nice, especially when at the start of building something, I can get quite confused about that's on top and what's at the bottom.
- I don't like the way you control the camera. I know the camera control as it is now is very normal, but still, I don't like it. SR3D Builder also as this camera control as default, but it has a setting to use "LDD-like" camera control and I like that so much more. I've tried to use this type for camera control in SR3D Builder for quite some time, but I wasn't able to use it as easy and as quickly as the "LDD-like" one. And, more importantly, can get quite dizzy with this type of camera control. I have no idea why....
- It would be nice if it would automaticly color the selected bricks when I select another color.

Other than those (personal) things, I haven't found anything that just doesn't work (bugs). Again, it looks very nice to me and I'm definitely trying to get more used to it

Btw, thanks for the tip to use + in the parts bin, that was exactly what I was looking for!

[Roland Melkert]

It looks more like the older version now, maybe I'll add an internal color/theme editor one day to make this kind of tweaking easier.

[Roland Melkert]

I think we can solve some of your points.

- You could place a real baseplate part at 0,0,0 when starting a model or maybe use a custom placeholder .dat with something flat.

- The default camera is a trackball control, as far I know that's the 3D standard as it's impossible to 'gimbal lock' and thus gives you 100% rotational freedom. But if you like the LDD way better you can set the camera into a similar mode by clicking on the 'TBL' text at the right bottom of the compass (visible in Jason's picture above). While in that (SPN) mode you can't tilt left/right anymore and only rotate up to 180 degrees forward/backwards.

- A double click on a wheel segment will apply it imminently instead of just stetting the working color.

Hope that helps.

[Jason Smith]

It looks more like the older version now, maybe I'll add an internal color/theme editor one day to make this kind of tweaking easier.

That would be an awesome feature, thank you.

A quick question, how do I select a whole bunch of parts at once? I think I'm looking for a click drag and select everything but that's just moving the camera.

[Roland Melkert]

Actually that's one key feature which is still missing, mainly because I keep postponing it as I'm not sure how to handle the depth while selecting.

I'll put it on my to do list for 1.5, If anyone has some ideas on this point I'm very open to suggestions.

In the mean time you might be able to partly select the parts needed by using the select menu.

[Jason Smith]

Ya I thought about the depth issue as well. Maybe when evoked the selection box could be 3d ish allowing us to rotate the camera about adjusting all the angles before we execute the selection. Similar to when we crop a photo but more of a 3d perspective. Otherwise to start off with just a simple draw and select everything. Even just a keypress to disable the camera and allow a click and selection draw.

[Jason Smith]

Bug report:

When I click on a previous 1-6 tab in the parts bin it sometimes it often doesn't switch the name to that filter tab unless I go back out then in again. Sometimes I need to click on a un-filtered tab to make it switch but then it will get stuck on the first filtered tab I select.

For example:

- I'm in tab 4 which is beams and tab 3 is pins.
- I click on tab 3 and the parts switch to pins but the filter name stays on beams.
- If I go back to tab 4 and then to tab 3 it might switch to pins.
- Sometimes I have to go to say tab 6 that isn't used to get it to switch.

Filters - Bush | Axle | Shock

[Roland Melkert]

I redone the shortcut keys table.

http://www.melkert.net/LDCad/docs/keys

I'm pretty sure it holds everything as I walked the keyboard handling source code.

[Roland Melkert]

Seems I've been a bit to greedy while recycling OpenGL resources. It seems to be visual only so it should not interfere with the filter results.

Thanks for reporting I'll fix it for the one.

[Philippe Hurbain]

I'm trying to do an animation (rotor of 42020 helicopter B-model). Got it to work fine when I attach the script to the submodel referencing the rotor and crank submodels to be animated (no rocket science since it's just an adaptation of your video). But I can't seem to be able to do that from main level model, I guess I'm missing a referencing step... I have had a look at the example scripts that come with LDCad but it didn't help me much despite the detailed comments you provide - I must say I am always struggling with high level languages ("My favorite programming language? Soldering iron!").

Edit... I am still interessed in the answer for projects to come, but I realized that the submodels I created (following official BIs) were not fitting mechanical entities and were thus not suitable anyway for animation. So I inlined intermediate submodel.

[Philippe Hurbain]

I just realized that LDCad doesn't complain when it opens a model with missing part in library. No need to open a dialog box for each instance of a missing part (and request to press a button for each as in MLCad!!!), but some warning would be useful...

[Philippe Hurbain]

Groups:
- how do I name groups? I see from your examples that it's possible, but I don't find this in the interface.
- Is it possible to add a part to an existing group?

[Max Martin Richter]

Maybe all missing parts could be saved in an array and displayed afterwards in one warning window?!

/Max

[Philippe Hurbain]

Yes, that's what LDView does, it works well...

[Roland Melkert]

Did you link to the subfile/model the reference to the rotor lives in? This is needed when the reference you want to use is not in the top level ldr (as ldc.subfile() links to toplevel by default), e.g.:

Code:

local roof=ldc.subfile('roof.ldr')
local rotor1=roof:getRef('rotorpart.dat', 1)
local rotor2=roof:getRef('rotorpart.dat', 2)

Alternatively you could create a nested group at top level, but if it's a single part or submodel you want to rotate walking the model tree is the better / cleaner solution.

Groups can be (re)named by opening the selection properties dialog, click on the coordinates panel or enter key while the group is selected.

You can add items to a group by selecting it, followed by also selecting the items you want to add from the grouping menu (listed one level up in the default sel rightclick menu) and then choose 'add selection to group'.

[Roland Melkert]

Currently missing parts are only mentioned in the logfile and rendered using red crosses (which you can still move around etc).

I have been thinking about adding a special dialog or part bin group for listing missing files, but up to now I never really needed it myself and thus forgot all about it

[Philippe Hurbain]

Did you link to the subfile/model the reference to the rotor lives in? This is needed when the reference you want to use is not in the top level ldr (as ldc.subfile() links to toplevel by default), e.g.:

Code:

local roof=ldc.subfile('roof.ldr')
local rotor1=roof:getRef('rotorpart.dat', 1)
local rotor2=roof:getRef('rotorpart.dat', 2)

Obvious now that you tell me! And works fine... (42020-B2.zip)

Alternatively you could create a nested group at top level, but if it's a single part or submodel you want to rotate walking the model tree is the better / cleaner solution.

Maybe cleaner, but nested group has a big plus: it makes animation independant of subfiles organized for building sequence, not for mechanical functional groups.
I tried this idea, but I clearly have a group origin problem that make them rotate around world origin... Tried many things, but always the same result
See 42020-B-nestedGr.zip

Groups can be (re)named by opening the selection properties dialog, click on the coordinates panel or enter key while the group is selected.

Why group properties entry doesn't appear in grouping menu you described below?

You can add items to a group by selecting it, followed by also selecting the items you want to add from the grouping menu (listed one level up in the default sel rightclick menu) and then choose 'add selection to group'.

I wouldn't have found this menu alone...
Same question for submodel: is it possible to move a part from top level to existing subfile?

[Roland Melkert]

I'm sorry your script is correct minus a minor detail (you need to compensate for the non id group ori), but the groups should rotate around their main item position not the abs 0,0,0 origin like it does now.

It seems you discovered a bug concerning the nested groups ori only manipulations it goes wrong when the main group item is not at toplevel. I'll fix this for the next version, in the mean time you could try building the correct matrix your self or make the groups at the level their main part is at and rotate them from there.

Funny this never was a problem in my demo animations and yet it's the first thing a new user walks into

On the group properties, it's not in the group menu because I thought it's more of a selection thing. But you are right that's probably the place where most people would look for it, so I will add a properties item to it.

You can move any part to any level in the model tree through nesting mode combined with a correct 'insertion target'. While in nesting mode click on any part you know is part of the model you want to move something to. Then click the 'insert into' text in the session panel. This will change the insertion target for all editing activities. Next you select the part(s) you want to move and select 'move to current level' from the selection menu.

I do this (probably way to fast ) in the 2nd animation tutorial as I discovered I forgot to add the wheel's pin to the axle1 sub model.

Do note there is a known bug when you do this and the selection you want to move contains grouped items (will also be fixed in the next version). So it's provably best to un group any grouped things you want to move first.

[Roland Melkert]

I've looked into this a bit more and it turns out it's not a group matrix bug, it's event related. Nesting is fun but all the internal matrix stuff introduced rounding problems in my early alpha's after a couple of frames so I implemented caching etc. Problem is the current version only initializes this cache when the start event is used in your script. This is why my examples all work fine

Anyhow a workaround is very simple, just add a (dummy) start event handler. Here is your corrected script it should work on your existing model without problems now.

Code:

function register()
  local ani=ldc.animation('42020-B')
  ani:setLength(5)
  ani:setEvent('frame', 'onFrame')
  ani:setEvent('start', 'onStart')
end

function onStart()
  --grp ori bug prevention
end
  
function onFrame()
  local ani=ldc.animation.getCurrent()
  local mainSf=ldc.subfile()
  local ori=ldc.matrix()

  local angle=720*ani:getFrameTime()/ani:getLength()
  
  ax1=mainSf:getGroup('crank')
  ori:set(0, 0, 1, 0, 1, 0, -1, 0, 0) --group has non id main item
  ori:mulRotateAB(angle, 1, 0, 0)
  ax1:setOri(ori)
  
  local ax2=mainSf:getGroup('TopRotor')
  ori:set(0, 0, 1, -1, 0, 0, 0, -1, 0)  --group has non id main item
  ori:mulRotateAB(-angle, 0, 1, 0)
  ax2:setOri(ori)
  
  local ax3=mainSf:getGroup('TailRotor')
  ori:setRotate(angle, 1, 0, 0)
  ax3:setOri(ori)

end

register()

I also corrected for the non id placements. The next version won't need the workaround anymore.

[Trevor Sandy]

I think being able to select "connected" parts would satisfy this request. It's also a common feature of CAD SW. One approach could be to look at tolerance between parts to determine if they are "connected."

[Jason Smith]

Would a in program, active model animation script building tool be worth looking into? For example you've made a simple model with an axle and gear. A user could select the script building tool which would pop up and ask you to fill in the basics such as animation time etc, hit next and it asks you what parts you want to animate, hit next and fill in the movements and in the background it would write the script. I'm not a programmer so I have no idea on the implications of what I'm asking so forgive me. I'm guessing many of the lines are the same for each animation, it's really just specific variables such as parts, movements etc. The basics such as which sub file or part locations could be pre-filled in the background when the part is selected. The very basic animation attributes such as animation time could also be asked during the set up.

I think keeping the user within the program and simplifying the process would make it more user friendly and approachable.

Sorry if this is too crazy of an idea.

[Roland Melkert]

I did consider adding a built in script editor, but dropped it thinking most people have some kind of favorite editor they like best when programming/scripting.

As for generating basic scripts, the problem is there are quite a few variables even for very simple model/animations. So the user would have to fill out a whole list of questions they might not completely grasp (like rotation vector directions etc).

With 1.5 I'm considering extending the scripting api into macro's so you can also generate (sub) models using script. With macro's in place it might be far more productive to let people write (and share) little scripts able to generate little starting scripts tailored to their own needs etc instead of having a couple of static wizards.

[Jason Smith]

I did consider adding a built in script editor, but dropped it thinking most people have some kind of favorite editor they like best when programming/scripting.

...With macro's in place it might be far more productive to let people write (and share) little scripts able to generate little starting scripts tailored to their own needs etc instead of having a couple of static wizards.

I hear ya, I guess I'm looking at it from a different perspective. I'm not a programmer, no nothing about scripting, just like to play with Lego. The requirement to program and script as a necessity for a huge and super cool feature of the program is going to limit it's usability for some. Again this is all a simple non programmers point of view. I'm your guy if you want usability suggestions for the simple person

[Philippe Hurbain]

Maybe you should have a look at SR3Dbuilder that does simple animations without any programming.

[Philippe Hurbain]

(you need to compensate for the non id group ori)

Could you elaborate on this? I see how to do this in your code, but I don't understand the rationale...

Funny this never was a problem in my demo animations and yet it's the first thing a new user walks into

Monkey test, you know...

[Roland Melkert]

(you need to compensate for the non id group ori)

Could you elaborate on this? I see how to do this in your code, but I don't understand the rationale...

groupetOri replaces the group's main item matrix rotational part. This is fine when that's an id but if not you will loose the original orientation. To prevent that you need to ADD the animation rotation to the existing rest state. I usually use the start event to cache the rest state if needed, but in the above script i just copied and paste the rotation from the group properties dialog.

[Jason Smith]

Maybe you should have a look at SR3Dbuilder that does simple animations without any programming.

I've used it and liked it. It's animation ability is what set it apart from MLCad but since the authors sad passing the future of it is uncertain. I was just thinking that LDCad would make an excellent alternative and I'm sure it will for many since it appears to be the only Lego CAD program actively supported (Windows and Linux). This is an awesome program and since I work in Ubuntu it saves me from dual booting. I can live without animations.

Keep up the great work Roland

[Jason Smith]

I was watching your video and was amazed at how quickly you were able to place pieces. I'm just starting to get used to the select and "insert" a part method, I love it! I've 50% quicker now.

Is it possible to assign the insert function to the mouse somehow? I find I can do most things without using the KB but often have to reach and hit the insert button. Would be cool and even faster if say a middle click or some other button was able to insert.

[Jason Smith]

Oh my goodness, the rubber, chain etc templates are so easy. Of course I tried it the super hard way first which took a while and was messy.

[Roland Melkert]

Oh my goodness, the rubber, chain etc templates are so easy.

Glad you like it.

Is it possible to assign the insert function to the mouse somehow?

The middle mouse button is already assigned, but I'm considering implementing custom key bindings in 1.5 (or maybe 1.6 depending on free time etc).

But it probably would still be faster to use the mouse/kb combo while working with angled technic models like the one from you picture above.

[Roland Melkert]

Question to the Linux users:

I was playing around in the new Ubuntu 14.10 and Kubuntu 14.10 releases with beta 2, and I noticed some of the arrow keys seem to misbehave.

It's very weird because it seems to vary between Linux versions (Ubuntu does weird with left/right while Kubuntu only seems to dislike down.)

As far I know this was ok in the previous versions of Ubuntu/Kubuntu. Anyone having these problems on other distro's?

[Jason Smith]

I've only used this on 12.04, soon to be 14.04. What's happening exactly?

[Roland Melkert]

It seems (e.g. during part rotation while inserting) to pause the gui on those key events freezing the gui until you click somewhere with the mouse or (sometimes) press the key again.

[Jason Smith]

I have had that happen, but not very often. I also get a whole gui freeze in a similar fashion if I leave it open in the background and come back to the program some time later. Usually takes a click or more to wake it up again.

[Richard Speyer]

I've noticed it on Slackware. I thought it was my keyboard (which is a it dodgy.)
It's the down key for me.

[Jason Smith]

What determines the angle at which parts enter the workspace from the parts bin? I'm working on a project with some angles as you know. I'm doing something wrong causing parts to come in at all wonky angles causing me to have to change the placement mode to fine and rotation to 1 degree to correct them.

[Roland Melkert]

Parts are always inserted using the orientation of the last selection. You can reset the ori for the 'floating' part by pressing 'home' before placement. Or by ctrl+home (on a selection) after placement.

Also while working with angled models like yours you'll probably want to change the grid orientation now and then to match alignment with the thing you want to add stuff to (e.g. one beam parallel to another.). This is done using 'o' on a selection, when done use 'o' again while nothing is selected to go back to the normal grid.

The upcoming updated manual will address this way of working a deeper.

[Jason Smith]

Ah, I get it, thank you. I need to start using that home key more often. Maybe I'll make a keyboard overlay or print out a cheat sheet or something.

[Roland Melkert]

I think i fixed it.

It seems to be caused by the default ((k)ubuntu menu nav) handling for those keys which the new version now blocks for the 3D panel.