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README.md

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+# NX Curve Sampling
+
+The NX Curve Sampling user function will read coordinates on a curve and print the coordinates of uniformly
+spaced points along the curve to the "Information" window. This is typically used to transfer coordinates to
+other tools, such as robot path planners, that need curve information based on CAD geometry.
+
+The uniform points are generated using the `UF_MODL_ask_curve_points` NX Open function.
+
+## Download
+
+See "Releases" for built files. The `nx_curve_sampler.dll` file is a compiled version of the user function.
+
+## Usage
+
+The `nx_curve_sampler.dll` is an "NX Open" function that is applied to a model. Begin by opening a model
+that has a curve to be sampled. Click "File" -> "Execute" -> "NX Open".
+
+![](docs/figures/execute_nx_open.png)
+
+Select `nx_curve_sampling.dll` in the open dialog and click "OK".
+
+Set the "Chord", "Angle", and "Point distance" parameters.
+
+| Parameter | Definition | Remarks |
+| ---       | ---        | ---     |
+| Chord | Chordal tolerance | Maximum allowable distance from a chord to the curve between ends of the chord |
+| Angle | Angular tolerance | Maximum allowable sum of the angles between the chord and the tangents to the curve at the ends of the chord |
+| Point distance | Maximum allowable chordal length | |
+
+Click OK once the parameters have been configured.
+
+![](docs/figures/parameters.png)
+
+"Select a Curve" will be displayed. Click on the curve of interest. The "Information" window will
+show with the coordinates of the points on the curve. The points will also be displayed on the part.
+Cut and paste the coordinates from the "Information" window to a text file or Excel.
+
+![](docs/figures/curve_selected.png)
+
+Press "Cancel" to exit the curve selection. Use "Undo" to remove the points from the object if they do not clear.
+
+# Building
+
+The user function is compiled using CMake. The DLL must be built using Visual Studio 2015 (toolkit v140). This
+can be selected during configuration. The Visual Studio 2015 C++ Toolchain can be installed using the Visual Studio
+Installer, and is an optional package available for all versions of Visual Studio. The `NX_ROOT_DIR` CMake variable
+can be used to specify the install location of NX if it is not detected automatically.
+
+Most users will not need to build the DLL, and can use the binary file found in "Releases".
+