Add script to generate KiCad footprints from keyboard layouts

.gitignore

@@ -26,3 +26,5 @@ fp-info-cache
 # Exported BOM files
 *.xml
 *.csv
+
+*.old

scripts/layout2footprint.py

@@ -0,0 +1,132 @@
+#!/usr/bin/env python3
+
+from argparse import ArgumentParser
+from json import loads
+from os.path import dirname, join, realpath
+from time import time
+
+SCRIPT_DIR = dirname(realpath(__file__))
+
+def compute_dimensions(layout):
+    max_x = 0
+
+    x = 0
+    y = 0
+    shape_override = {}
+    for row in layout:
+        # ignore metadata
+        if isinstance(row, dict):
+            continue
+
+        for key in row:
+            if isinstance(key, dict):
+                x += key.get('x', 0)
+                y += key.get('y', 0)
+                shape_override = key
+                continue
+
+            x += shape_override.get('w', 1)
+            shape_override = {}
+
+        max_x = max(x, max_x)
+        x = 0
+        y += 1
+
+    return (max_x, y)
+
+def make_rect(x, y, w, h):
+    return [
+        (x,   y  ),
+        (x+w, y  ),
+        (x+w, y+h),
+        (x,   y+h),
+    ]
+
+def write(f, points, r):
+    points = ' '.join(map(lambda p: f'(xy {p[0]} {p[1]})', points))
+    f.write(f'  (fp_poly (pts {points}) (layer F.Cu) (width {2*r}))\n')
+    f.write(f'  (fp_poly (pts {points}) (layer F.Mask) (width {2*r-0.05}))\n')
+
+def plot_shape(f, shape, args, offset_x, offset_y):
+    p = args.padding
+    r = args.radius
+    s = args.scale
+
+    coord = lambda c: (c+p)*s+r
+    dim = lambda d: (d-2*p)*s-2*r
+
+    points = make_rect(coord(shape['x'])+offset_x, coord(shape['y'])+offset_y, dim(shape['w']), dim(shape['h']))
+    write(f, points, r)
+
+    if shape['x'] != shape['x2'] or shape['y'] != shape['y2'] or shape['w'] != shape['w2'] or shape['h'] != shape['h2']:
+        points = make_rect(coord(shape['x2'])+offset_x, coord(shape['y2'])+offset_y, dim(shape['w2']), dim(shape['h2']))
+        write(f, points, r)
+
+if __name__ == '__main__':
+    parser = ArgumentParser()
+    parser.add_argument('-p', '--padding', default=0.1, type=float)
+    parser.add_argument('-r', '--radius', default=0.1, type=float)
+    parser.add_argument('-s', '--scale', default=1.905, type=float)
+    parser.add_argument('layout', help='path to layout file')
+    parser.add_argument('name', help='name of generated footprint')
+    args = parser.parse_args()
+
+    with open(args.layout) as f:
+        layout = loads(f.read())
+
+    w, h = compute_dimensions(layout)
+    offset_x = -w*args.scale/2
+    offset_y = -h*args.scale/2
+
+    name = args.name
+    out_path = join(SCRIPT_DIR, f'../kezboard-pcb.pretty/{name}.kicad_mod')
+    with open(out_path, 'w') as f:
+        f.write(f'''
+(module {name} (layer F.Cu) (tedit {hex(int(time()))[2:].upper()})
+  (descr "tiny kezboard is tiny")
+  (attr virtual)
+  (fp_text reference REF** (at 0 {offset_y-1}) (layer F.SilkS) hide
+    (effects (font (size 1 1) (thickness 0.15)))
+  )
+  (fp_text value {name} (at 0 {-(offset_y-1)}) (layer F.Fab) hide
+    (effects (font (size 1 1) (thickness 0.15)))
+  )
+'''.lstrip())
+
+        x = 0
+        y = 0
+        shape_override = {}
+        for row in layout:
+            # ignore metadata
+            if isinstance(row, dict):
+                continue
+
+            for key in row:
+                if isinstance(key, dict):
+                    x += key.get('x', 0)
+                    y += key.get('y', 0)
+                    shape_override = key
+                    continue
+
+                w = shape_override.get('w', 1)
+                h = shape_override.get('h', 1)
+                shape = {
+                    'x': x,
+                    'y': y,
+                    'w': w,
+                    'h': h,
+                    'x2': x+shape_override.get('x2', 0),
+                    'y2': y+shape_override.get('y2', 0),
+                    'w2': shape_override.get('w2', w),
+                    'h2': shape_override.get('h2', h),
+                }
+
+                plot_shape(f, shape, args, offset_x, offset_y)
+
+                x += shape['w']
+                shape_override = {}
+
+            x = 0
+            y += 1
+
+        f.write(')\n')