[NAB] Documentation updates

README.md

@@ -3,29 +3,32 @@
 Fully integrated system to convert GDSII format files, such as the ones exported from Cadence Virtuoso, into SVG graphics for printing or display.
 
 Prerequisites:
-- [.NET 5](https://dotnet.microsoft.com/download/dotnet)
+- [.NET 6](https://dotnet.microsoft.com/download/dotnet)
+- [Clipper 2](https://github.com/AngusJohnson/Clipper2) (included)
 
 Should work on Windows, Linux, and Mac. Theoretically big-endian platforms are also supported (untested).
 
 ## Usage
 1) Export your layout as GDSII format from the CAD software you're using. (see below)
 2) Run this utility in info mode to determine layers, by running `GDStoSVG.exe <myfile.gds> -info`
-3) It will output design units and layer info to the console. Using this layer list, and the generated SVG file (same name as the input GDS), locate components on a specific layer (all items on a layer are grouped together), and determine what each layer ID corresponds to.
-    - If your SVG file is too large to open, you may want to export only a sub-unit to start, by using the `-unit <UNIT>` parameter, with one of the units listed from step 2.
-4) Create a CSV file with your layer IDs, names, colours, and opacities in the required format (see `GDStoSVG.exe -help` for info).
-5) Test your CSV file by running `GDStoSVG.exe <myfile.gds> -csv <layers.csv> -info`.
-6) Repeat until you are happy with the layer assignments, and there are no unassigned layers remaining (unless you don't care about those layers).
+3) Using the layer list the tool outputs and the generated SVG file (same name as the input GDS), determine what each layer ID corresponds to in your PDK's stackup
+    - If your SVG file is too large to open, you may want to export only a sub-unit to start, by using the `-unit <UNIT>` parameter, with one of the units listed from step 2
+4) Create a CSV file with your layer IDs, names, colours, and opacities in the required format:
+    - `<Name>,<ID in range -32768 to 32767>,<Colour, RRGGBB hex>,<Opacity in range 0.0 to 1.0>`
+    - Example: `M1,50,3333CC,0.8`
+5) Test your CSV file by running `GDStoSVG.exe <myfile.gds> -csv <layers.csv> -info`
+6) Repeat until you are happy with the layer assignments, and there are no unassigned layers remaining (unless you don't care about those layers)
 7) The CSV can be reused for any further exports using the same PDK. In the future, simply run `GDStoSVG.exe <myfile.gds> -csv <layer.csv> [-svg output.svg]`
+8) You can optionally export with `-optimize` to attempt to simplify the resulting geometry into as few shapes as possible. This will make the process take much longer, but is still several orders of magnitude faster than a union operation in Inkscape
 
 ## Exporting from Cadence Virtuoso 6.1.6
-1) From the main Virtuoso window, go to File -> Export -> Stream.
-2) Type in a file name, and select your library and top-level cell.
-3) Make sure "Translate entire hierarchy" is checked on the "General" tab.
-4) Other default configuration should be OK.
-5) Use the exported GDS file as directed above.
+1) From the main Virtuoso window, go to File -> Export -> Stream
+2) Type in a file name, and select your library and top-level cell
+3) Make sure "Translate entire hierarchy" is checked on the "General" tab
+4) Other default configuration should be OK
+5) Use the exported GDS file as directed above
 
 ## Notes
 - This is still unfinished. Expect bugs.
-- Polygons and paths are output as-is. This means a ton of individual, potentially overlapping polygons. You may want to run a Union in Inkscape or similar software to resolve this.
 - Text is not fully working yet.
 - Arrays are not yet implemented.