summaryrefslogtreecommitdiff
path: root/gerbonara/cad/primitives.py
blob: 472cb32c9bc508268bdc5b6a23b9f5365cd86c4c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
import sys
import math
import warnings
from copy import copy
from itertools import zip_longest, chain
from dataclasses import dataclass, field, KW_ONLY
from collections import defaultdict

from ..utils import LengthUnit, MM, rotate_point, svg_arc, sum_bounds, bbox_intersect, Tag, offset_bounds
from ..layers import LayerStack
from ..graphic_objects import Line, Arc, Flash
from ..apertures import Aperture, CircleAperture, ObroundAperture, RectangleAperture, ExcellonTool
from ..newstroke import Newstroke


def sgn(x):
    return -1 if x < 0 else 1


class KeepoutError(ValueError):
    def __init__(self, obj, keepout, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.obj = obj
        self.keepout = keepout


newstroke_font = None


class Board:
    def __init__(self, w=None, h=None, corner_radius=1.5, center=False, default_via_hole=0.4, default_via_diameter=0.8, x=0, y=0, rotation=0, unit=MM):
        self.x, self.y = x, y
        self.rotation = 0
        self.objects = []
        self.outline = []
        self.extra_silk_top = []
        self.extra_silk_bottom = []
        self.keepouts = []
        self.default_via_hole = MM(default_via_hole, unit)
        self.default_via_diameter = MM(default_via_diameter, unit)
        self.unit = unit
        if w or h:
            if w and h:
                self.rounded_rect_outline(w, h, r=corner_radius, center=center)
                self.w, self.h = w, h
            else:
                raise ValueError('Either both, w and h, or neither of them must be given.')
        else:
            self.w = self.h = None

    @property
    def abs_pos(self):
        return self.x, self.y, self.rotation, False

    def add_silk(self, side, obj):
        if side not in ('top', 'bottom'):
            raise ValueError('side must be one of "top" or "bottom".')

        if side == 'top':
            self.extra_silk_top.append(obj)
        else:
            self.extra_silk_bottom.append(obj)

    def add_text(self, *args, **kwargs):
        self.objects.append(Text(*args, **kwargs))

    def add_keepout(self, bbox, unit=MM):
        ((_x_min, _y_min), (_x_max, _y_max)) = bbox
        self.keepouts.append(MM.convert_bounds_from(unit, bbox))

    def add(self, obj, keepout_errors='raise'):
        if keepout_errors not in ('ignore', 'raise', 'warn', 'skip'):
            raise ValueError('keepout_errors must be one of "ignore", "raise", "warn" or "skip".')

        if keepout_errors != 'ignore':
            for ko in self.keepouts:
                if obj.overlaps(ko, unit=MM):
                    if keepout_errors == 'warn':
                        warnings.warn(f'Object with bounds {obj.bounding_box(MM)} [mm] hits one or more keepout areas')
                    elif keepout_errors == 'raise':
                        raise KeepoutError(obj, ko, msg)
                    return

        obj.parent = self
        self.objects.append(obj)

    def via(self, x, y, diameter=None, hole=None, keepout_errors='raise', unit=MM):
        diameter = diameter or unit(self.default_via_dia, MM)
        hole = hole or unit(self.default_via_hole, MM)
        obj = Via(x, y, diameter, hole, unit=unit, keepout_errors=keepout_errors)
        self.add(obj)
        return obj

    def rounded_rect_outline(self, w, h, r=0, x0=None, y0=None, center=False, unit=MM):
        if x0 is None:
            x0 = -w/2 if center else 0
        if y0 is None:
            y0 = -h/2 if center else 0

        ap = CircleAperture(0.05, unit=MM)

        self.outline.append(Line(x0+r, y0, x0+w-r, y0, ap, unit=unit))
        if r:
            self.outline.append(Arc(x0+w-r, y0, x0+w, y0+r, 0, r, False, ap, unit=unit))
        self.outline.append(Line(x0+w, y0+r, x0+w, y0+h-r, ap, unit=unit))
        if r:
            self.outline.append(Arc(x0+w, y0+h-r, x0+w-r, y0+h, -r, 0, False, ap, unit=unit))
        self.outline.append(Line(x0+w-r, y0+h, x0+r, y0+h, ap, unit=unit))
        if r:
            self.outline.append(Arc(x0+r, y0+h, x0, y0+h-r, 0, -r, False, ap, unit=unit))
        self.outline.append(Line(x0, y0+h-r, x0, y0+r, ap, unit=unit))
        if r:
            self.outline.append(Arc(x0, y0+r, x0+r, y0, r, 0, False, ap, unit=unit))

    def layer_stack(self, layer_stack=None):
        if layer_stack is None:
            layer_stack = LayerStack()

        cache = {}
        for obj in chain(self.objects):
            obj.render(layer_stack, cache)

        layer_stack['mechanical', 'outline'].objects.extend(self.outline)
        layer_stack['top', 'silk'].objects.extend(self.extra_silk_top)
        layer_stack['bottom', 'silk'].objects.extend(self.extra_silk_bottom)

        return layer_stack

    def svg(self, margin=0, arg_unit=MM, svg_unit=MM, force_bounds=None):
        return self.layer_stack().to_svg(margin=margin, arg_unit=arg_unit, svg_unit=svg_unit,
                                                 force_bounds=force_bounds)

    def pretty_svg(self, side='top', margin=0, arg_unit=MM, svg_unit=MM, force_bounds=None, inkscape=False, colors=None):
        return self.layer_stack().to_pretty_svg(side=side, margin=margin, arg_unit=arg_unit, svg_unit=svg_unit,
                                                   force_bounds=force_bounds, inkscape=inkscape, colors=colors)


@dataclass
class Positioned:
    x: float
    y: float
    _: KW_ONLY
    rotation: float = 0.0
    flip: bool = False
    unit: LengthUnit = MM
    parent: object = None

    @property
    def abs_pos(self):
        if self.parent is None:
            px, py, pa, pf = 0, 0, 0, False
        else:
            px, py, pa, pf = self.parent.abs_pos

        return self.x+px, self.y+py, self.rotation+pa, (bool(self.flip) != bool(pf))

    def bounding_box(self, unit=MM):
        stack = LayerStack()
        self.render(stack)
        objects = chain(*(l.objects for l in stack.graphic_layers.values()),
                        stack.drill_pth.objects, stack.drill_npth.objects)
        objects = list(objects)
        #print('foo', type(self).__name__,
        #      [(type(obj).__name__, [prim.bounding_box() for prim in obj.to_primitives(unit)]) for obj in objects], file=sys.stderr)
        return sum_bounds(prim.bounding_box() for obj in objects for prim in obj.to_primitives(unit))

    def overlaps(self, bbox, unit=MM):
        return bbox_intersect(self.bounding_box(unit), bbox)

    @property
    def single_sided(self):
        return True


@dataclass
class Graphics(Positioned):
    top_copper: list = field(default_factory=list)
    top_mask: list = field(default_factory=list)
    top_silk: list = field(default_factory=list)
    top_paste: list = field(default_factory=list)
    bottom_copper: list = field(default_factory=list)
    bottom_mask: list = field(default_factory=list)
    bottom_silk: list = field(default_factory=list)
    bottom_paste: list = field(default_factory=list)
    drill_npth: list = field(default_factory=list)
    drill_pth: list = field(default_factory=list)

    def render(self, layer_stack, cache=None):
        x, y, rotation, flip = self.abs_pos
        top, bottom = ('bottom', 'top') if flip else ('top', 'bottom')

        for target, source in [
                (layer_stack[top, 'copper'],    self.top_copper),
                (layer_stack[top, 'mask'],      self.top_mask),
                (layer_stack[top, 'silk'],      self.top_silk),
                (layer_stack[top, 'paste'],     self.top_paste),
                (layer_stack[bottom, 'copper'], self.bottom_copper),
                (layer_stack[bottom, 'mask'],   self.bottom_mask),
                (layer_stack[bottom, 'silk'],   self.bottom_silk),
                (layer_stack[bottom, 'paste'],  self.bottom_paste),
                (layer_stack.drill_pth,         self.drill_pth),
                (layer_stack.drill_npth,        self.drill_npth)]:

            for fe in source:
                fe = copy(fe)
                fe.rotate(rotation)
                fe.offset(x, y, self.unit)
                target.objects.append(fe)

    def bounding_box(self, unit=MM):
        if math.isclose(self.rotation, 0, abs_tol=1e-3):
            return offset_bounds(sum_bounds((obj.bounding_box(unit=unit) for obj in chain(
                    self.top_copper,
                    self.top_mask,
                    self.top_silk,
                    self.top_paste,
                    self.bottom_copper,
                    self.bottom_mask,
                    self.bottom_silk,
                    self.bottom_paste,
                    self.drill_npth,
                    self.drill_pth,
                ))), unit(self.x, self.unit), unit(self.y, self.unit))
        else:
            return super().bounding_box(unit)

    @property
    def single_sided(self):
        any_top = self.top_copper or self.top_mask or self.top_paste or self.top_silk
        any_bottom = self.bottom_copper or self.bottom_mask or self.bottom_paste or self.bottom_silk
        any_drill = self.drill_npth or self.drill_pth
        return not (any_drill or (any_top and any_bottom))


@dataclass
class ObjectGroup(Positioned):
    objects: list = field(default_factory=list)

    def render(self, layer_stack, cache=None):
        for obj in self.objects:
            if not isinstance(obj, Positioned):
                raise ValueError(f'ObjectGroup members must be children of Positioned, not {type(obj)}')

            obj.parent = self
            obj.render(layer_stack, cache=cache)

    def bounding_box(self, unit=MM):
        if math.isclose(self.rotation, 0, abs_tol=1e-3):
            return offset_bounds(sum_bounds((obj.bounding_box(unit=unit) for obj in self.objects)),
                                 unit(self.x, self.unit), unit(self.y, self.unit))
        else:
            return super().bounding_box(unit)

    @property
    def single_sided(self):
        return all(obj.single_sided for obj in self.objects)


@dataclass
class Text(Positioned):
    text: str
    font_size: float = 2.5
    stroke_width: float = 0.25
    h_align: str = 'left'
    v_align: str = 'bottom'
    layer: str = 'silk'
    polarity_dark: bool = True

    def render(self, layer_stack, cache=None):
        obj_x, obj_y, rotation, flip = self.abs_pos
        global newstroke_font

        if newstroke_font is None:
            newstroke_font = Newstroke()

        strokes = list(newstroke_font.render(self.text, size=self.font_size))
        if not strokes:
            return

        xs = [x for points in strokes for x, _y in points]
        ys = [y for points in strokes for _x, y in points]
        min_x, min_y, max_x, max_y = min(xs), min(ys), max(xs), max(ys)

        if self.h_align == 'left':
            x0 = 0
        elif self.h_align == 'center':
            x0 = -max_x/2
        elif self.h_align == 'right':
            x0 = -max_x
        else:
            raise ValueError('h_align must be one of "left", "center", or "right".')

        if self.v_align == 'top':
            y0 = -(max_y - min_y)
        elif self.v_align == 'middle':
            y0 = -(max_y - min_y)/2
        elif self.v_align == 'bottom':
            y0 = 0
        else:
            raise ValueError('v_align must be one of "top", "middle", or "bottom".')

        if self.side == 'bottom':
            x0 += min_x + max_x
            x_sign = -1
        else:
            x_sign = 1

        ap = CircleAperture(self.stroke_width, unit=self.unit)

        for stroke in strokes:
            for (x1, y1), (x2, y2) in zip(stroke[:-1], stroke[1:]):
                obj = Line(x0+x_sign*x1, y0-y1, x0+x_sign*x2, y0-y2, aperture=ap, unit=self.unit, polarity_dark=self.polarity_dark)
                obj.rotate(rotation)
                obj.offset(obj_x, obj_y)
                layer_stack['bottom' if flip else 'top', self.layer].objects.append(obj)

    def bounding_box(self, unit=MM):
        approx_w = len(self.text)*self.font_size*0.75 + self.stroke_width
        approx_h = self.font_size + self.stroke_width

        if self.h_align == 'left':
            x0 = 0
        elif self.h_align == 'center':
            x0 = -approx_w/2
        elif self.h_align == 'right':
            x0 = -approx_w

        if self.v_align == 'top':
            y0 = -approx_h
        elif self.v_align == 'middle':
            y0 = -approx_h/2
        elif self.v_align == 'bottom':
            y0 = 0

        return (self.x+x0, self.y+y0), (self.x+x0+approx_w, self.y+y0+approx_h)


@dataclass
class Pad(Positioned):
    pad_stack: PadStack

    @property
    def single_sided(self):
        return self.pad_stack.single_sided


@dataclass(frozen=True, slots=True)
class PadStackAperture:
    aperture: Aperture
    side: str
    layer: str
    offset_x: float = 0 # in PadStack units
    offset_y: float = 0
    rotation: float = 0


@dataclass(frozen=True, slots=True)
class PadStack:
    _: KW_ONLY
    unit: LengthUnit = MM

    @property
    def apertures(self):
        raise NotImplementedError()

    def flashes(self, x, y, rotation: float = 0, flip: bool = False):
        for ap in self.apertures:
            aperture = ap.aperture.rotated(ap.rotation + rotation)
            fl = Flash(ap.offset_x, ap.offset_y)
            fl.rotate(rotation)
            fl.offset(x, y)
            side = fl.side
            if flip:
                side = {'top': 'bottom', 'bottom': 'top'}.get(side, side)
            yield side, fl.layer, fl

    def render(self, layer_stack, x, y, rotation: float = 0, flip: bool = False):
        for side, layer, flash in self.flashes(x, y, rotation, flip):
            if side == 'drill' and use == 'plated':
                layer_stack.drill_pth.objects.append(flash)

            elif side == 'drill' and use == 'nonplated':
                layer_stack.drill_npth.objects.append(flash)

            elif (side, layer) in layer_stack:
                layer_stack[side, layer].objects.append(flash)

    @property
    def single_sided(self):
        return len({ap.side for ap in self.apertures}) <= 1


@dataclass(frozen=True, slots=True)
class SMDStack(PadStack):
    aperture: Aperture
    mask_expansion: float = 0.0
    paste_expansion: float = 0.0
    paste: bool = True
    flip: bool = False

    @property
    def side(self):
        return 'bottom' if self.flip else 'top'

    @property
    def apertures(self):
        yield PadStackAperture(self.aperture, self.side, 'copper')
        yield PadStackAperture(self.aperture.dilated(self.mask_expansion, self.unit), self.side, 'mask')
        if self.paste:
            yield PadStackAperture(self.aperture.dilated(self.paste_expansion, self.unit), self.side, 'paste')

    @classmethod
    def rect(kls, w, h, rotation=0, mask_expansion=0.0, paste_expansion=0.0, paste=True, flip=False, unit=MM):
        ap = RectangleAperture(w, h, unit=unit).rotated(rotation)
        return kls(ap, mask_expansion, paste_expansion, paste, flip, unit=unit)

    @classmethod
    def circle(kls, dia, mask_expansion=0.0, paste_expansion=0.0, paste=True, flip=False, unit=MM):
        return kls(CircleAperture(dia, unit=unit), mask_expansion, paste_expansion, paste, flip, unit=unit)
    

@dataclass(frozen=True, slots=True)
class THTPad(PadStack):
    drill_dia: float
    pad_top: SMDStack
    pad_bottom: SMDStack = None
    aperture_inner: Aperture = None
    plated: bool = True

    def __post_init__(self):
        if self.pad_bottom is None:
            object.__setattr__(self, 'pad_bottom', replace(self.pad_top, flip=True))

        if self.pad_top.flip:
            raise ValueError('top pad cannot be flipped')

    @property
    def plating(self):
        return 'plated' if self.plated else 'nonplated'

    @property
    def apertures(self):
        yield from self.pad_top.apertures
        yield from self.pad_bottom.apertures
        yield PadStackAperture(self.aperture_inner, 'inner', 'copper')
        yield PadStackAperture(ExcellonTool(self.drill_dia, plated=self.plated, unit=self.unit), 'drill', self.plating)

    @property
    def single_sided(self):
        return False

    @classmethod
    def rect(kls, drill_dia, w, h, rotation=0, mask_expansion=0.0, paste_expansion=0.0, paste=True, plated=True, unit=MM):
        pad = SMDStack.rect(w, h, rotation, mask_expansion, paste_expansion, paste, unit=unit)
        return kls(drill_dia, pad, plated=plated)

    @classmethod
    def circle(kls, drill_dia, dia, rotation=0, mask_expansion=0.0, paste_expansion=0.0, paste=True, plated=True, unit=MM):
        pad = SMDStack.circle(dia, rotation, mask_expansion, paste_expansion, paste, unit=unit)
        return kls(drill_dia, pad, plated=plated)

    @classmethod
    def obround(kls, drill_dia, w, h, rotation=0, mask_expansion=0.0, paste_expansion=0.0, paste=True, plated=True, unit=MM):
        ap = ObroundAperture(w, h, unit=unit).rotated(rotation)
        pad = SMDStack(ap, mask_expansion, paste_expansion, paste, unit=unit)
        return kls(drill_dia, pad, plated=plated)

@dataclass(frozen=True, slots=True)
class ThroughViaStack(PadStack):
    hole: float
    dia: float = None
    tented: bool = True

    def __post_init__(self):
        if self.dia == None:
            object.__setattr__(self, 'dia', self.hole*2)

    @property
    def single_sided(self):
        return False

    @property
    def apertures(self):
        copper_aperture = CircleAperture(self.dia, unit=self.unit)
        yield PadStackAperture(copper_aperture, 'top', 'copper')
        yield PadStackAperture(copper_aperture, 'bottom', 'copper')
        yield PadStackAperture(copper_aperture, 'inner', 'copper')
        if self.tented:
            yield PadStackAperture(copper_aperture, 'top', 'mask')
            yield PadStackAperture(copper_aperture, 'bottom', 'mask')
        yield PadStackAperture(ExcellonTool(self.hole, plated=True, unit=self.unit), 'drill', 'plated')


@dataclass(frozen=True, slots=True)
class Via(Positioned):
    pad_stack: PadStack

    def render(self, layer_stack, cache=None):
        x, y, rotation, flip = self.abs_pos
        self.pad_stack.render(layer_stack, x, y, rotation, flip)

    @classmethod
    def at(kls, x, y, hole, dia=None, tented=True, unit=MM):
        return kls(x, y, ThroughViaStack(hole, dia, tented, unit=unit), unit=unit)


@dataclass
class Trace:
    width: float
    start: object = None
    end: object = None
    waypoints: [(float, float)] = field(default_factory=list)
    style: str = 'oblique'
    orientation: [str] = tuple() # 'cw' or 'ccw'
    roundover: float = 0
    side: str = 'top'
    unit: LengthUnit = MM
    parent: object = None

    DIRECT = 'direct'
    OBLIQUE = 'oblique'
    ORTHO = 'ortho'

    CW = 'cw'
    CCW = 'ccw'

    def _route(self, p1, p2, orientation):
        x1, y1 = p1
        x2, y2 = p2
        dx = x2-x1
        dy = y2-y1

        yield p1

        if self.style == 'direct' or \
                math.isclose(x1, x2, abs_tol=1e-6) or math.isclose(y1, y2, abs_tol=1e-6) or \
                (self.style == 'oblique' and math.isclose(dx, dy, abs_tol=1e-6)):
            return

        p = (abs(dy) > abs(dx)) == ((dx >= 0) == (dy >= 0))
        if self.style == 'oblique':
            if p == (orientation == 'cw'):
                if abs(dy) > abs(dx):
                    yield (x1, y1+sgn(dy)*(abs(dy)-abs(dx)))
                else:
                    yield (x1+sgn(dx)*(abs(dx)-abs(dy)), y1)
            else:
                if abs(dy) > abs(dx):
                    yield (x2, y1+sgn(dy)*abs(dx))
                else:
                    yield (x1+sgn(dx)*abs(dy), y2)

        else: # self.style == 'ortho'
            if p == (orientation == 'cw'):
                if abs(dy) > abs(dx):
                    yield (x1, y2)
                else:
                    yield (x2, y1)
            else:
                if abs(dy) > abs(dx):
                    yield (x2, y1)
                else:
                    yield (x1, y2)

    @classmethod
    def _midpoint(kls, p1, p2):
        x1, y1 = p1
        x2, y2 = p2
        dx = x2 - x1
        dy = y2 - y1
        xm = x1 + dx / 2
        ym = y1 + dy / 2
        return (xm, ym)

    @classmethod
    def _point_on_line(kls, p1, p2, dist_from_p1):
        x1, y1 = p1
        x2, y2 = p2
        dx = x2 - x1
        dy = y2 - y1
        dist = math.dist(p1, p2)
        if math.isclose(dist, 0, abs_tol=1e-6):
            return p2
        xm = x1 + dx / dist * dist_from_p1
        ym = y1 + dy / dist * dist_from_p1
        return (xm, ym)

    @classmethod
    def _angle_between(kls, p1, p2, p3):
        x1, y1 = p1
        x2, y2 = p2
        x3, y3 = p3
        x1, y1 = x1 - x2, y1 - y2
        x3, y3 = x3 - x2, y3 - y2
        dot_product = x1*x3 + y1*y3
        l1 = math.hypot(x1, y1)
        l2 = math.hypot(x3, y3)
        norm = dot_product / l1 / l2
        return math.acos(min(1, max(-1, norm)))

    def _round_over(self, points, aperture):
        if math.isclose(self.roundover, 0, abs_tol=1e-6) or len(points) <= 2:
            import sys
            for p1, p2 in zip(points[:-1], points[1:]):
                yield Line(*p1, *p2, aperture=aperture, unit=self.unit)
            return
        # here: len(points) >= 3

        line_b = Line(*points[0], *self._midpoint(points[0], points[1]), aperture=aperture, unit=self.unit)

        for p1, p2, p3 in zip(points[:-2], points[1:-1], points[2:]):
            x1, y1 = p1
            x2, y2 = p2
            x3, y3 = p3
            xa, ya = pa = self._midpoint(p1, p2)
            xb, yb = pb = self._midpoint(p2, p3)
            la = math.dist(pa, p2)
            lb = math.dist(p2, pb)

            alpha = self._angle_between(p1, p2, p3)
            if alpha == 0:
                l = Line(line_b.x1, line_b.y1, *p2, aperture=aperture, unit=self.unit)
                line_b = Line(*p2, *pb, aperture=aperture, unit=self.unit)
                yield l
                continue
            tr = self.roundover/math.tan(alpha/2)
            t = min(la, lb, tr)
            r = t*math.tan(alpha/2)

            xs, ys = ps = self._point_on_line(p2, pa, t)
            xe, ye = pe = self._point_on_line(p2, pb, t)

            if math.isclose(t, la, abs_tol=1e-6):
                if not math.isclose(line_b.curve_length(), 0, abs_tol=1e-6):
                    yield line_b
                xs, ys = ps = pa
            else:
                yield Line(line_b.x1, line_b.y1, xs, ys, aperture=aperture, unit=self.unit)

            if math.isclose(t, lb, abs_tol=1e-6):
                xe, ye = pe = pb
            line_b = Line(*pe, *pb, aperture=aperture, unit=self.unit)

            if math.isclose(r, 0, abs_tol=1e-6):
                continue

            xc = -(y2 - ys) / t * r
            yc = +(x2 - xs) / t * r

            xsr = xs - x2
            ysr = ys - y2
            xer = xe - x2
            yer = ye - y2
            cross_product_z = xsr * yer - ysr * xer

            clockwise = cross_product_z > 0
            if clockwise:
                xc, yc = -xc, -yc
            
            yield Arc(*ps, *pe, xc, yc, clockwise, aperture=aperture, unit=self.unit)

        yield Line(line_b.x1, line_b.y1, x3, y3, aperture=aperture, unit=self.unit)
        
    def _to_graphic_objects(self):
        start, end = self.start, self.end

        if not isinstance(start, tuple):
            *start, _rotation = start.abs_pos
        if not isinstance(end, tuple):
            *end, _rotation = end.abs_pos

        aperture = CircleAperture(diameter=self.width, unit=self.unit)

        points_in = [start, *self.waypoints, end]

        points = []
        for p1, p2, orientation in zip_longest(points_in[:-1], points_in[1:], self.orientation):
            points.extend(self._route(p1, p2, orientation))
        points.append(p2)

        return self._round_over(points, aperture)

    def render(self, layer_stack, cache=None):
        layer_stack[self.side, 'copper'].objects.extend(self._to_graphic_objects())

def _route_demo():
    from ..utils import setup_svg, Tag

    def pd_obj(objs):
        objs = list(objs)
        yield f'M {objs[0].x1}, {objs[0].y1}'
        for obj in objs:
            if isinstance(obj, Line):
                yield f'L {obj.x2}, {obj.y2}'
            else:
                assert isinstance(obj, Arc)
                yield svg_arc(obj.p1, obj.p2, obj.center_relative, obj.clockwise)

    pd = lambda points: f'M {points[0][0]}, {points[0][1]} ' + ' '.join(f'L {x}, {y}' for x, y in points[1:])

    font = Newstroke()

    tags = []
    for n in range(0, 8*6):
        theta = 2*math.pi / (8*6) * n
        dx, dy = math.cos(theta), math.sin(theta)

        strokes = list(font.render(f'α={n/(8*6)*360}', size=0.2))
        xs = [x for st in strokes for x, _y in st]
        ys = [y for st in strokes for _x, y in st]
        min_x, min_y, max_x, max_y = min(xs), min(ys), max(xs), max(ys)

        xf = f'translate({n//6*1.1 + 0.1} {n%6*1.3 + 0.3}) scale(0.5 0.5) translate(1 1)'
        txf = f'{xf} translate(0 -1.2) translate({-(max_x-min_x)/2} {-max_y})'

        tags.append(Tag('circle', cx='0', cy='0', r='1',
                        fill='none', stroke='black', opacity='0.5', stroke_width='0.01',
                        transform=xf))
        tags.append(Tag('path',
                        fill='none',
                        stroke='black', opacity='0.5', stroke_width='0.02', stroke_linejoin='round', stroke_linecap='round',
                        transform=txf, d=' '.join(pd(points) for points in strokes)))

        #for r in [0.0, 0.1, 0.2, 0.3]:
        for r in [0, 0.2]:
            #tr = Trace(0.1, style='ortho', roundover=r, start=(0, 0), end=(dx, dy))
            tr = Trace(0.1, style='oblique', roundover=r, start=(dx, dy), end=(0, 0))
            #points_cw = list(tr._route((0, 0), (dx, dy), 'cw')) + [(dx, dy)]
            #points_ccw = list(tr._route((0, 0), (dx, dy), 'ccw')) + [(dx, dy)]
            tr.orientation = ['cw']
            objs_cw = tr._to_graphic_objects()
            tr.orientation = ['ccw']
            objs_ccw = tr._to_graphic_objects()

            tags.append(Tag('path',
                            fill='none',
                            stroke='red', stroke_width='0.01', stroke_linecap='round',
                            transform=xf, d=' '.join(pd_obj(objs_cw))))
            tags.append(Tag('path',
                            fill='none',
                            stroke='blue', stroke_width='0.01', stroke_linecap='round',
                            transform=xf, d=' '.join(pd_obj(objs_ccw))))
            #tags.append(Tag('path',
            #                fill='none',
            #                stroke='red', stroke_width='0.01', stroke_linecap='round',
            #                transform=xf, d=pd(points_cw)))
            #tags.append(Tag('path',
            #                fill='none',
            #                stroke='blue', stroke_width='0.01', stroke_linecap='round',
            #                transform=xf, d=pd(points_ccw)))


    print(setup_svg([Tag('g', tags, transform='scale(20 20)')], [(0, 0), (20*10*1.1 + 0.1, 20*10*1.3 + 0.1)]))


def _board_demo():
    b = Board(100, 80)
    p1 = THTPad.rect(10, 10, 0.9, 1.8)
    b.add(p1)
    p2 = THTPad.rect(20, 15, 0.9, 1.8)
    b.add(p2)
    b.add(Trace(0.5, p1, p2, style='ortho', roundover=1.5))
    b.add_text(50, 50, 'Foobar')
    print(b.pretty_svg())
    b.layer_stack().save_to_directory('/tmp/testdir')


if __name__ == '__main__':
    _board_demo()
    #_route_demo()