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-# topas-create-custom-mlc
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+# topas-create-custom-mlc
+
+## A GUI to automatically create a TOPAS-readable MLC simulation file
+
+Modern MLCs can have very compley leaf designs. Since not all geometries can be build using TOPAS, this script creates a custom MLC architecture from a CAD file describing a single leaf (.stl). Using a GUI, the positions of up to 64 leaf pairs can be individually customized - simply limited by the screen height. However, an arbitary amount of leaf pairs can be positioned using rectangular fields, or using presets.
+
+## Usage
+
+Before starting the script, a couple of options need to be set to fit the program to your .stl file.
+
+Change the values in the \###Setup\### portion of the script to match your requirements:
+
+- leaf_stl_path : Let TOPAS know where to find the .stl file describing the leaf
+- number_of_leaf_pairs : Number of leaf pairs in the MLC
+- MLC-TransZ : Distance from the Source to the top of the MLC, in cm
+- SSD : Source-Surface-Distance, in cm
+- dist_from_xy_plane_to_top_edge : Z-Coordinate of the .stl environment (ideally this would be 0), in mm
+- dist_from_z_axis_to_inner_edge : X-/Y-Coordinate of the .stl environment (deviation from centre axis), in mm  
+
+## Preview
+ 
+![Preview](https://user-images.githubusercontent.com/87897942/146832691-24346005-0484-402b-82e8-90ebb472417a.png)
+
+## Dependencies
+
+Requires python3, numpy, and tkinter.