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Diffstat (limited to 'gerbonara/gerber/graphic_primitives.py')
| -rw-r--r-- | gerbonara/gerber/graphic_primitives.py | 403 |
1 files changed, 0 insertions, 403 deletions
diff --git a/gerbonara/gerber/graphic_primitives.py b/gerbonara/gerber/graphic_primitives.py deleted file mode 100644 index 65aa28c..0000000 --- a/gerbonara/gerber/graphic_primitives.py +++ /dev/null @@ -1,403 +0,0 @@ - -import math -import itertools - -from dataclasses import dataclass, KW_ONLY, replace - - -@dataclass -class GraphicPrimitive: - _ : KW_ONLY - polarity_dark : bool = True - - -def rotate_point(x, y, angle, cx=0, cy=0): - """ rotate point (x,y) around (cx,cy) clockwise angle radians """ - - return (cx + (x - cx) * math.cos(-angle) - (y - cy) * math.sin(-angle), - cy + (x - cx) * math.sin(-angle) + (y - cy) * math.cos(-angle)) - -def min_none(a, b): - if a is None: - return b - if b is None: - return a - return min(a, b) - -def max_none(a, b): - if a is None: - return b - if b is None: - return a - return max(a, b) - -def add_bounds(b1, b2): - (min_x_1, min_y_1), (max_x_1, max_y_1) = b1 - (min_x_2, min_y_2), (max_x_2, max_y_2) = b2 - min_x, min_y = min_none(min_x_1, min_x_2), min_none(min_y_1, min_y_2) - max_x, max_y = max_none(max_x_1, max_x_2), max_none(max_y_1, max_y_2) - return ((min_x, min_y), (max_x, max_y)) - -def rad_to_deg(x): - return x/math.pi * 180 - -@dataclass -class Circle(GraphicPrimitive): - x : float - y : float - r : float # Here, we use radius as common in modern computer graphics, not diameter as gerber uses. - - def bounding_box(self): - return ((self.x-self.r, self.y-self.r), (self.x+self.r, self.y+self.r)) - - def to_svg(self, tag, fg, bg): - color = fg if self.polarity_dark else bg - return tag('circle', cx=self.x, cy=self.y, r=self.r, style=f'fill: {color}') - - -@dataclass -class Obround(GraphicPrimitive): - x : float - y : float - w : float - h : float - rotation : float # radians! - - def to_line(self): - if self.w > self.h: - w, a, b = self.h, self.w-self.h, 0 - else: - w, a, b = self.w, 0, self.h-self.w - return Line( - *rotate_point(self.x-a/2, self.y-b/2, self.rotation, self.x, self.y), - *rotate_point(self.x+a/2, self.y+b/2, self.rotation, self.x, self.y), - w, polarity_dark=self.polarity_dark) - - def bounding_box(self): - return self.to_line().bounding_box() - - def to_svg(self, tag, fg, bg): - return self.to_line().to_svg(tag, fg, bg) - - -def arc_bounds(x1, y1, x2, y2, cx, cy, clockwise): - # This is one of these problems typical for computer geometry where out of nowhere a seemingly simple task just - # happens to be anything but in practice. - # - # Online there are a number of algorithms to be found solving this problem. Often, they solve the more general - # problem for elliptic arcs. We can keep things simple here since we only have circular arcs. - # - # This solution manages to handle circular arcs given in gerber format (with explicit center and endpoints, plus - # sweep direction instead of a format with e.g. angles and radius) without any trigonometric functions (e.g. atan2). - # - # cx, cy are relative to p1. - - # Center arc on cx, cy - cx += x1 - cy += y1 - x1 -= cx - x2 -= cx - y1 -= cy - y2 -= cy - clockwise = bool(clockwise) # bool'ify for XOR/XNOR below - - # Calculate radius - r = math.sqrt(x1**2 + y1**2) - - # Calculate in which half-planes (north/south, west/east) P1 and P2 lie. - # Note that we assume the y axis points upwards, as in Gerber and maths. - # SVG has its y axis pointing downwards. - p1_west = x1 < 0 - p1_north = y1 > 0 - p2_west = x2 < 0 - p2_north = y2 > 0 - - # Calculate bounding box of P1 and P2 - min_x = min(x1, x2) - min_y = min(y1, y2) - max_x = max(x1, x2) - max_y = max(y1, y2) - - # North - # ^ - # | - # |(0,0) - # West <-----X-----> East - # | - # +Y | - # ^ v - # | South - # | - # +-----> +X - # - # Check whether the arc sweeps over any coordinate axes. If it does, add the intersection point to the bounding box. - # Note that, since this intersection point is at radius r, it has coordinate e.g. (0, r) for the north intersection. - # Since we know that the points lie on either side of the coordinate axis, the '0' coordinate of the intersection - # point will not change the bounding box in that axis--only its 'r' coordinate matters. We also know that the - # absolute value of that coordinate will be greater than or equal to the old coordinate in that direction since the - # intersection with the axis is the point where the full circle is tangent to the AABB. Thus, we can blindly set the - # corresponding coordinate of the bounding box without min()/max()'ing first. - - # Handle north/south halfplanes - if p1_west != p2_west: # arc starts in west half-plane, ends in east half-plane - if p1_west == clockwise: # arc is clockwise west -> east or counter-clockwise east -> west - max_y = r # add north to bounding box - else: # arc is counter-clockwise west -> east or clockwise east -> west - min_y = -r # south - else: # Arc starts and ends in same halfplane west/east - # Since both points are on the arc (at same radius) in one halfplane, we can use the y coord as a proxy for - # angle comparisons. - small_arc_is_north_to_south = y1 > y2 - small_arc_is_clockwise = small_arc_is_north_to_south == p1_west - if small_arc_is_clockwise != clockwise: - min_y, max_y = -r, r # intersect aabb with both north and south - - # Handle west/east halfplanes - if p1_north != p2_north: - if p1_north == clockwise: - max_x = r # east - else: - min_x = -r # west - else: - small_arc_is_west_to_east = x1 < x2 - small_arc_is_clockwise = small_arc_is_west_to_east == p1_north - if small_arc_is_clockwise != clockwise: - min_x, max_x = -r, r # intersect aabb with both north and south - - return (min_x+cx, min_y+cy), (max_x+cx, max_y+cy) - - -def point_line_distance(l1, l2, p): - # https://en.wikipedia.org/wiki/Distance_from_a_point_to_a_line - x1, y1 = l1 - x2, y2 = l2 - x0, y0 = p - length = math.dist(l1, l2) - if math.isclose(length, 0): - return math.dist(l1, p) - return ((x2-x1)*(y1-y0) - (x1-x0)*(y2-y1)) / length - -def svg_arc(old, new, center, clockwise): - r = math.hypot(*center) - # invert sweep flag since the svg y axis is mirrored - sweep_flag = int(not clockwise) - # In the degenerate case where old == new, we always take the long way around. To represent this "full-circle arc" - # in SVG, we have to split it into two. - if math.isclose(math.dist(old, new), 0): - intermediate = old[0] + 2*center[0], old[1] + 2*center[1] - # Note that we have to preserve the sweep flag to avoid causing self-intersections by flipping the direction of - # a circular cutin - return f'A {r:.6} {r:.6} 0 1 {sweep_flag} {intermediate[0]:.6} {intermediate[1]:.6} ' +\ - f'A {r:.6} {r:.6} 0 1 {sweep_flag} {new[0]:.6} {new[1]:.6}' - - else: # normal case - d = point_line_distance(old, new, (old[0]+center[0], old[1]+center[1])) - large_arc = int((d < 0) == clockwise) - return f'A {r:.6} {r:.6} 0 {large_arc} {sweep_flag} {new[0]:.6} {new[1]:.6}' - -@dataclass -class ArcPoly(GraphicPrimitive): - """ Polygon whose sides may be either straight lines or circular arcs """ - - # list of (x : float, y : float) tuples. Describes closed outline, i.e. first and last point are considered - # connected. - outline : [(float,)] - # must be either None (all segments are straight lines) or same length as outline. - # Straight line segments have None entry. - arc_centers : [(float,)] = None - - @property - def segments(self): - ol = self.outline - return itertools.zip_longest(ol, ol[1:] + [ol[0]], self.arc_centers or []) - - def bounding_box(self): - bbox = (None, None), (None, None) - for (x1, y1), (x2, y2), arc in self.segments: - if arc: - clockwise, (cx, cy) = arc - bbox = add_bounds(bbox, arc_bounds(x1, y1, x2, y2, cx, cy, clockwise)) - - else: - line_bounds = (min(x1, x2), min(y1, y2)), (max(x1, x2), max(y1, y2)) - bbox = add_bounds(bbox, line_bounds) - return bbox - - def __len__(self): - return len(self.outline) - - def __bool__(self): - return bool(len(self)) - - def _path_d(self): - if len(self.outline) == 0: - return - - yield f'M {self.outline[0][0]:.6} {self.outline[0][1]:.6}' - - for old, new, arc in self.segments: - if not arc: - yield f'L {new[0]:.6} {new[1]:.6}' - else: - clockwise, center = arc - yield svg_arc(old, new, center, clockwise) - - def to_svg(self, tag, fg, bg): - color = fg if self.polarity_dark else bg - return tag('path', d=' '.join(self._path_d()), style=f'fill: {color}') - -class Polyline: - def __init__(self, *lines): - self.coords = [] - self.polarity_dark = None - self.width = None - - for line in lines: - self.append(line) - - def append(self, line): - assert isinstance(line, Line) - if not self.coords: - self.coords.append((line.x1, line.y1)) - self.coords.append((line.x2, line.y2)) - self.polarity_dark = line.polarity_dark - self.width = line.width - return True - - else: - x, y = self.coords[-1] - if self.polarity_dark == line.polarity_dark and self.width == line.width \ - and math.isclose(line.x1, x) and math.isclose(line.y1, y): - self.coords.append((line.x2, line.y2)) - return True - - else: - return False - - def to_svg(self, tag, fg, bg): - color = fg if self.polarity_dark else bg - if not self.coords: - return None - - (x0, y0), *rest = self.coords - d = f'M {x0:.6} {y0:.6} ' + ' '.join(f'L {x:.6} {y:.6}' for x, y in rest) - width = f'{self.width:.6}' if not math.isclose(self.width, 0) else '0.01mm' - return tag('path', d=d, style=f'fill: none; stroke: {color}; stroke-width: {width}; stroke-linejoin: round; stroke-linecap: round') - -@dataclass -class Line(GraphicPrimitive): - x1 : float - y1 : float - x2 : float - y2 : float - width : float - - def bounding_box(self): - r = self.width / 2 - return add_bounds(Circle(self.x1, self.y1, r).bounding_box(), Circle(self.x2, self.y2, r).bounding_box()) - - def to_svg(self, tag, fg, bg): - color = fg if self.polarity_dark else bg - width = f'{self.width:.6}' if not math.isclose(self.width, 0) else '0.01mm' - return tag('path', d=f'M {self.x1:.6} {self.y1:.6} L {self.x2:.6} {self.y2:.6}', - style=f'fill: none; stroke: {color}; stroke-width: {width}; stroke-linecap: round') - -@dataclass -class Arc(GraphicPrimitive): - x1 : float - y1 : float - x2 : float - y2 : float - # absolute coordinates - cx : float - cy : float - clockwise : bool - width : float - - def bounding_box(self): - r = self.width/2 - endpoints = add_bounds(Circle(self.x1, self.y1, r).bounding_box(), Circle(self.x2, self.y2, r).bounding_box()) - - arc_r = math.dist((self.cx, self.cy), (self.x1, self.y1)) - - # extend C -> P1 line by line width / 2 along radius - dx, dy = self.x1 - self.cx, self.y1 - self.cy - x1 = self.x1 + dx/arc_r * r - y1 = self.y1 + dy/arc_r * r - - # same for C -> P2 - dx, dy = self.x2 - self.cx, self.y2 - self.cy - x2 = self.x2 + dx/arc_r * r - y2 = self.y2 + dy/arc_r * r - - arc = arc_bounds(x1, y1, x2, y2, self.cx, self.cy, self.clockwise) - return add_bounds(endpoints, arc) # FIXME add "include_center" switch - - def to_svg(self, tag, fg, bg): - color = fg if self.polarity_dark else bg - arc = svg_arc((self.x1, self.y1), (self.x2, self.y2), (self.cx, self.cy), self.clockwise) - width = f'{self.width:.6}' if not math.isclose(self.width, 0) else '0.01mm' - return tag('path', d=f'M {self.x1:.6} {self.y1:.6} {arc}', - style=f'fill: none; stroke: {color}; stroke-width: {width}; stroke-linecap: round; fill: none') - -def svg_rotation(angle_rad, cx=0, cy=0): - return f'rotate({float(rad_to_deg(angle_rad)):.4} {float(cx):.6} {float(cy):.6})' - -@dataclass -class Rectangle(GraphicPrimitive): - # coordinates are center coordinates - x : float - y : float - w : float - h : float - rotation : float # radians, around center! - - def bounding_box(self): - return self.to_arc_poly().bounding_box() - - def to_arc_poly(self): - sin, cos = math.sin(self.rotation), math.cos(self.rotation) - sw, cw = sin*self.w/2, cos*self.w/2 - sh, ch = sin*self.h/2, cos*self.h/2 - x, y = self.x, self.y - return ArcPoly([ - (x - (cw+sh), y - (ch+sw)), - (x - (cw+sh), y + (ch+sw)), - (x + (cw+sh), y + (ch+sw)), - (x + (cw+sh), y - (ch+sw)), - ]) - - @property - def center(self): - return self.x + self.w/2, self.y + self.h/2 - - def to_svg(self, tag, fg, bg): - color = fg if self.polarity_dark else bg - x, y = self.x - self.w/2, self.y - self.h/2 - return tag('rect', x=x, y=y, width=self.w, height=self.h, - transform=svg_rotation(self.rotation, self.x, self.y), style=f'fill: {color}') - -@dataclass -class RegularPolygon(GraphicPrimitive): - x : float - y : float - r : float - n : int - rotation : float # radians! - - def to_arc_poly(self): - ''' convert n-sided gerber polygon to normal ArcPoly defined by outline ''' - - delta = 2*math.pi / self.n - - return ArcPoly([ - (self.x + math.cos(self.rotation + i*delta) * self.r, - self.y + math.sin(self.rotation + i*delta) * self.r) - for i in range(self.n) ]) - - def bounding_box(self): - return self.to_arc_poly().bounding_box() - - def to_svg(self, tag, fg, bg): - return self.to_arc_poly().to_svg(tag, fg, bg) - |