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ibl format specifications


New member
I need to write an .ibl exporter but I can't find the spec in the behemoth of a website at ptc.

Can anyone point me to the right page?
This was taken from Pro/E help:

Importing a Datum Curve

An imported datum curve can consist of one or more segments. Multiple segments are not necessarily connected.

The From File option imports a datum curve from a Pro/ENGINEER .ibl, IGES, SET, or VDA file. Pro/ENGINEER does not automatically combine the curves imported using From File into a composite curve.

Pro/ENGINEER reads all the curves from an IGES or SET file, then converts them to spline curves. When you import a VDA

file, the system reads the VDA spline entities only.

The .ibl file format is very much like that of a blend file, except you should precede the coordinates of each segment of the curve with both begin section and begin curve. Two points in a section define a line, while more than two define a spline.

To connect curve segments, make sure the coordinates of the first point are the same as the last point in the previous


You can redefine datum curves that are created from a file and you can trim or split them with other curves that are imported from a file.

Also do a search on:

Example: Sample Datum Curve File

A simple example using arclength blending is given in the help.
Try another search on:

Example: Importing Blend File

PTC documentation is extremely poor on ibl files, it's hard to find what arcwise blending and pointwise blending is.

From experience for pointwise blending the number of data points per section must be the same, if not use arclength (i.e. blending from one line segment to another).

One interesting thing occurs if you import curves from file and import an iges file. If you then go in and redefine to edit the datum-curve file Pro/E will write a file called feat_1111.ibl

You can use this to see ibl structure for yourself...


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