setup and tutorial for
running LSynth through MLCad

This tutorial will teach you how to set up MLCad to run the hose and band synthesizer LSynth through MLCad's interface. Furthermore it will show you tips and tricks and help troubleshoot problems you might encounter. The tutorial takes for granted that you have followed the installation advice for the LDraw Parts Library and MLCad, you have further downloaded and installed the package with unofficial parts from the LDraw Parts Tracker, your LDraw system is running smoothly and that you are at least a little familiar with the building editor. The tutorial is based on MLCad 3.2 and LSynth 3.1 and is grouped into the following sections:

installing LSynth
setting up MLCad
creating a LSynth synthesis

download:    LSynth_mpd_3-1.zip (6 KB)

Unzip the content to the \bin\ folder located in LSynth's root, overwriting the already existing file (but make sure you have created a backup file first ).

Download also the package with the latest constraint files. The LSynth constraints will be treated as unofficial LDraw part files and stored in a special folder. Make sure you understand how unofficial parts should be included in programs such as MLCad by reading the tutorial to customize MLCad a bit through the MLCad.ini file first.:

download:    Constraints_3-1.zip (13 KB)

This tutorial assumes that the base directory for LDraw containing the \PARTS\ and \P\ folder as well as the \Unofficial\ folder is C:\Programs\LDraw. Create a subfolder named "LSynth" in \Unofficial\ and unpack the content.

Before we dive into the nuts'n'bolts of part synthesis we have to make sure that MLCad and LSynth work well together. First we have to tell MLCad the absolute path to LSynth containing the \Bin\ folder as well as the location of the constraint files. Please download the latest MLCad.ini file which ships with all the new exciting synthesis types supported by LSynth 3.1 from the MLCad.ini tutorial page.

Unzip the content in MLCad's root folder overwriting the already existing file (but make sure you have created a backup file first in case you have customized the file to your needs). Open the MLCad.ini file in an editor or a word-processing program and scroll down towards the end of the document where it reads:  

; 3 = SHOW <LDRAWDIR>Unofficial\Parts
; 4 = HIDE <LDRAWDIR>Unofficial\P
; 5 = SHOW <LDRAWDIR>Unofficial\LSynth

in order to read:

[SCAN_ORDER]
1 = SHOW <LDRAWDIR>Parts
2 = HIDE <LDRAWDIR>P
3 = SHOW <LDRAWDIR>Unofficial\Parts
4 = HIDE <LDRAWDIR>Unofficial\P
5 = SHOW <LDRAWDIR>Unofficial\LSynth

NOTE! In case MLCad is unable to read the <LDRAWDIR> keyword indicating relative paths you have to either define LDRAWDIR as environmental variable in your OS or omit the keyword altogether and define the absolute path (if your filename contains spaces, the entire filename must be enclosed in double quotes which is standard for any Windows command line with long filenames). According to the assumption above the code would be:

3 = SHOW "C:\Programs\LDraw\Unofficial\Parts"
4 = HIDE "C:\Programs\LDraw\Unofficial\P"
5 = SHOW "C:\Programs\LDraw\Unofficial\LSynth"

3.

Substitute "Define the absolute path to LSynth" with: "C:\Programs\LSynth":

[LSYNTH]
%PATH = "C:\Programs\LSynth"
; Axle, cable, hose and string types LSynth knows about:
00 - VERSION 3.1 = VERSION 3.1
01 - BRICK_ARC = SYNTH BEGIN BRICK_ARC 16
...
Visibility Statement: HIDE = SYNTH HIDE

; End of file

NOTE! We define the path containing the bin\ folder and NOT the program lsynthcp - the console based synthesizer that reads in the DAT file and writes out a new DAT file with the synthesized parts. The quotes are important in case your path contains blanks. 

Users already familiar with LSynth will also recognize the typical META commands needed to synthesize hoses and bands. At the top of the .ini file the more skilled users will also find additional information about this section. For now save your work and close the file.

To easily access the LSynth constraint parts in the parts tree as well as the parts preview window it is wise to add a new category to MLCad's Parts Library Tree. Please launch MLCad to set up the program:

4.

Select the Settings menu, the Parts Tree tab, then Tree Configuration... (Settings > Parts Tree > Tree Configuration...).

5.

This will pop up the Parts Tree Configuration dialog.

6.

Enter the following two statements in the boxes at the bottom of the dialog:

Name: LSynth
Search string: <LSynth

7.

You might change the order of the categories by clicking the Move Up or Move Down buttons.

8.

Confirm your insertion and exit the Parts Tree Configuration dialog by selecting OK. At this point your Parts Tree should list the LSynth constraints as following:

9.

Select Extras > LSynth > Add Command... or click on the Add Command icon in the Expert Toolbar.

10.

The LSynth Command dialog will pop up. The drop down box shows all the LSynth META statement previously inserted in the MLCad.ini file.

NOTE! The numbers in front of the meta commands have no other significance then to ensure that the statements get listed accordingly to their type instead of an alphabetical order.

11.

Pick the type you like and confirm your choice by clicking the OK button. For this tutorial we will move on using a simple TECHNIC_PNEUMATIC_HOSE.

12.

MLCad inserts the corresponding LSynth META statement followed by a SHOW and END statement.

SYNTH BEGIN TECHNIC_PNEUMATIC_HOSE 16
SYNTH SHOW
SYNTH END

The number at the end of the SYNTH BEGIN command defines the LDraw color number of the synthesized result.

13.

You might change the color once the synthesis has been generated by selecting all the synthesis parts using the menu Edit > Select > Same Type but, taking advantage of LSynth's color support , it's much more convenient defining the color right from the start. Select Edit > Modify... from the menu bar or click the appropriate icon in the Objectbar or directly double-click the comment in the File Parts List pane. This will open the Comment dialog.

14.

Substitute the default main color 16 with your desired LDraw color number and click the OK button. Make sure that Old style comment or meta command is checked.

NOTE! The default color 16 - Main Color is defined in the MLCad.ini file. Edit the file to change the color permanently:

01 ELECTRIC_NXT_CABLE = SYNTH BEGIN ELECTRIC_NXT_CABLE 25
11 TECHNIC_PNEUMATIC_HOSE = SYNTH BEGIN TECHNIC_PNEUMATIC_HOSE 4
...

15.

NOTE! To get a straight section in the synthesis made of a stretched element position your constraints on a virtual straight line. In the example above the blue constraint number 3 and the red end constraint share the same coordinates on the Y and Z axis.

17.

While the SYNTH END command is crucial only for LSynth the SYNTH SHOW statement will also be used by MLCad for internal handling, defining the hidden status of constraint parts and synthesized parts. All hose and band constraints MUST be placed between the visibility statement SYNTH SHOW or HIDE and the SYNTH END statement!

As pointed out above the provided constraints look different but will be treated by LSynth the same with the exception that constraints with green and red rings should be used exclusively for hose-type synthesis with a fixed lenght such as Minifig chains or Strings with a "xxL" identifier.
You can even use LS01.dat as start constraint, LS03.dat as pass-through and end with LS02.dat. It's just a matter of taste. This is even true for LS04.dat - LSynth Constraint Part - Type 4 - "String" or LS06.dat - LSynth Constraint Part - Type 6 - "Power Functions Cable" though they have been specially designed for the STRING_HOSE or a ELECTRIC_POWER_FUNCTIONS_CABLE.
You have however to take care how you're going to position them in the 3D-environment, because the constraints have two characteristics: the origin plane and the flag indicating its orientation:

• The origin defines the start and end points of the synthesis. In LS03.dat it is the bulls eye, in LS02.dat or LS04.dat the constraints' bottom. Do you wonder why the TECHNIC_RIBBED_HOSE's end in the image above does not meet the end constraints' bulls eye? Since the synthesis is build by parts with a fixed length there wasn't room left to fit in another ripped segment. If this happens you will have to re-arrange the synthesis parts a bit to fill the gap or move your end constraint out some LDUs (LDraw Units).
• The flag tells LSynth if it should rotate the individual parts making up the synthesis by some amount. Obviously the orientation/rotation has little influence on uniform synthesis parts like the TECHNIC_PNEUMATIC_HOSE or a STRING_HOSE unless there are no loops or complicated pass-throughs but it is vital for ELECTRIC_RCX_CABLE or ELECTRIC_NXT_CABLE.

18.

Once all constraints are in place choose Extras > LSynth > Run LSynth from the menu bar or click the icon with the command mirrored in the Expert Toolbar.

19.

When working on a new file which has never been saved, MLCad will ask you if you want to save your work before sending the package to LSynth. It is highly recommended to do so 'cos this will function as workaround for MLCad's missing Undo. This will be covered in greater detail later in the tutorial - for now save your work by naming it LSynth_Tutorial_Constraints-only.ldr.

20.

On a slow computer you will glimpse popping up a DOS command prompt window performing the synthesis and closing immediately afterwards. In fact MLCad does nothing else than creating a temporary file and batch-filing LSynth.

21.

Congratulation! At this point you should have created your first pneumatic hose. You haven't?! Have a look at the troubleshooting chapter.

23.

Once the synthesis has been performed MLCad assigns a hidden status to the constraint parts. Use the visibility commands from the Extras > LSynth menu or the icons in the Expert Toolbar to:

download:		LSynth_Tutorial_Constraints-only.zip	(1KB)
		LSynth_Tutorial_Synthesis.zip	(4 KB)

Happy lsynthing!