""" Minimal GD&T drawing engine (ASME Y14.5-2018 style, ANSI B sheet, third-angle projection). Views are true hidden-line projections of the CadQuery/OCCT solids (HLRBRep); sections cut the solid and hatch the cut faces. Annotations are placed with 3D model points, mapped into each view, so they stay attached to the geometry. Units on the sheet: inches. """ import math import numpy as np import matplotlib matplotlib.use("Agg") matplotlib.set_loglevel("error") import matplotlib.pyplot as plt from matplotlib.patches import Rectangle, Polygon, PathPatch from matplotlib.path import Path as MPath import cadquery as cq from OCP.HLRBRep import HLRBRep_Algo, HLRBRep_HLRToShape from OCP.HLRAlgo import HLRAlgo_Projector from OCP.gp import gp_Ax2, gp_Pnt, gp_Dir from OCP.TopExp import TopExp_Explorer from OCP.TopAbs import TopAbs_EDGE from OCP.BRepAdaptor import BRepAdaptor_Curve from OCP.GCPnts import GCPnts_QuasiUniformDeflection from OCP.TopoDS import TopoDS plt.rcParams["font.family"] = ["DejaVu Sans", "Segoe UI Symbol"] plt.rcParams["pdf.fonttype"] = 42 SW, SH = 17.0, 11.0 TXT = 0.115 * 72 # text height 0.115 in, in points SYM = {"position": "⌖", "perp": "⟂", "parallel": "∥", "flat": "⏥", "circ": "○", "cyl": "⌭", "runout": "↗", "trunout": "⌰", "profile": "⌓", "line": "⌒", "angular": "∠", "conc": "◎", "sym": "⌯", "dia": "⌀", "M": "Ⓜ", "L": "Ⓛ", "cbore": "⌴", "straight": "⏤", "csink": "⌵", "depth": "⌄"} D = SYM["dia"] VIEWS = { # X (sheet right), Y (sheet up), Z (towards the eye) "front": ((1, 0, 0), (0, 0, 1), (0, -1, 0)), "top": ((1, 0, 0), (0, 1, 0), (0, 0, 1)), "right": ((0, 1, 0), (0, 0, 1), (1, 0, 0)), "left": ((0, -1, 0), (0, 0, 1), (-1, 0, 0)), "bottom": ((1, 0, 0), (0, -1, 0), (0, 0, -1)), } def _edges_to_polylines(comp, defl): out = [] if comp is None or comp.IsNull(): return out ex = TopExp_Explorer(comp, TopAbs_EDGE) while ex.More(): e = TopoDS.Edge_s(ex.Current()) c = BRepAdaptor_Curve(e) d = GCPnts_QuasiUniformDeflection(c, defl) if d.IsDone() and d.NbPoints() > 1: out.append(np.array([(d.Value(i).X(), d.Value(i).Y()) for i in range(1, d.NbPoints() + 1)])) ex.Next() return out def hlr(shape, kind, defl=1e-3): X, Y, Z = VIEWS[kind] algo = HLRBRep_Algo() algo.Add(shape.wrapped) algo.Projector(HLRAlgo_Projector(gp_Ax2(gp_Pnt(0, 0, 0), gp_Dir(*Z), gp_Dir(*X)))) algo.Update() algo.Hide() h = HLRBRep_HLRToShape(algo) vis = _edges_to_polylines(h.VCompound(), defl) + _edges_to_polylines(h.OutLineVCompound(), defl) hid = _edges_to_polylines(h.HCompound(), defl) + _edges_to_polylines(h.OutLineHCompound(), defl) return vis, hid class View: def __init__(self, sheet, shape, kind, scale, center, label=None, section=None, hidden=True, hatch_faces=None, label_pos="below"): self.sheet, self.kind, self.scale = sheet, kind, scale self.X, self.Y, _ = (np.array(v, float) for v in VIEWS[kind]) vis, hid = hlr(shape, kind) allp = np.vstack(vis) if vis else np.zeros((1, 2)) self.u0 = (allp[:, 0].min() + allp[:, 0].max()) / 2 self.v0 = (allp[:, 1].min() + allp[:, 1].max()) / 2 self.cx, self.cy = center self.half_w = (allp[:, 0].max() - allp[:, 0].min()) / 2 * scale self.half_h = (allp[:, 1].max() - allp[:, 1].min()) / 2 * scale ax = sheet.ax if hidden: for pl in hid: s = self._uv(pl) ax.plot(s[:, 0], s[:, 1], color="0.45", lw=0.45, ls=(0, (4, 2.5)), zorder=2) for f in (hatch_faces or []): self._hatch(f) for pl in vis: s = self._uv(pl) ax.plot(s[:, 0], s[:, 1], color="k", lw=0.8, zorder=3) if label: if label_pos == "below": ax.text(self.cx, self.cy - self.half_h - 0.38, label, ha="center", va="top", fontsize=TXT * 1.05, weight="bold") elif label_pos == "above": ax.text(self.cx, self.cy + self.half_h + 0.2, label, ha="center", va="bottom", fontsize=TXT * 1.05, weight="bold") else: ax.text(label_pos[0], label_pos[1], label, ha="center", va="center", fontsize=TXT * 1.05, weight="bold") def _uv(self, pl): return np.c_[self.cx + (pl[:, 0] - self.u0) * self.scale, self.cy + (pl[:, 1] - self.v0) * self.scale] def m(self, p): p = np.asarray(p, float) return np.array([self.cx + (p @ self.X - self.u0) * self.scale, self.cy + (p @ self.Y - self.v0) * self.scale]) def _hatch(self, face): verts, codes = [], [] for w in [face.outerWire()] + list(face.innerWires()): pts = np.array([(p.x, p.y, p.z) for p in w.positions(list(np.linspace(0, 1, 160)))]) s = np.array([self.m(p) for p in pts]) verts += list(s) + [s[0]] codes += [MPath.MOVETO] + [MPath.LINETO] * (len(s) - 1) + [MPath.CLOSEPOLY] self.sheet.ax.add_patch(PathPatch(MPath(verts, codes), fc="none", ec="none", hatch="////", lw=0, zorder=1)) def section_cut(shape, axis, value, keep="+"): """Cut a solid with an axis-aligned plane; return (kept solid, list of cut faces on the plane).""" big = 200.0 lo, hi = (value, big) if keep == "+" else (-big, value) rng = {"x": (lo, hi, -big, big, -big, big), "y": (-big, big, lo, hi, -big, big), "z": (-big, big, -big, big, lo, hi)}[axis] b = cq.Solid.makeBox(rng[1] - rng[0], rng[3] - rng[2], rng[5] - rng[4], cq.Vector(rng[0], rng[2], rng[4])) kept = shape.intersect(b) idx = "xyz".index(axis) faces = [f for f in kept.Faces() if abs(f.Center().toTuple()[idx] - value) < 1e-6 and abs(abs(f.normalAt().toTuple()[idx]) - 1) < 1e-6] return kept, faces class Sheet: def __init__(self, dwg_no, title, material, finish, scale_txt, sheet_no, sheets, mass=None, rev="A", date="2026-10-02", notes=(), next_assy=""): self.fig = plt.figure(figsize=(SW, SH)) self.ax = self.fig.add_axes([0, 0, 1, 1]) ax = self.ax ax.set_xlim(0, SW); ax.set_ylim(0, SH); ax.set_aspect("equal"); ax.axis("off") ax.add_patch(Rectangle((0.4, 0.4), SW - 0.8, SH - 0.8, fc="none", ec="k", lw=1.6)) for i, z in enumerate("87654321"): # zone marks x = 0.4 + (i + 0.5) * (SW - 0.8) / 8 ax.text(x, SH - 0.28, z, ha="center", fontsize=8); ax.text(x, 0.22, z, ha="center", fontsize=8) for j, z in enumerate("DCBA"): y = 0.4 + (j + 0.5) * (SH - 0.8) / 4 ax.text(0.2, y, z, va="center", fontsize=8); ax.text(SW - 0.24, y, z, va="center", fontsize=8) self.dwg_no, self.notes = dwg_no, list(notes) self._title_block(dwg_no, title, material, finish, scale_txt, sheet_no, sheets, mass, rev, date, next_assy) # ------------------------------------------------------------------ title block / notes def _title_block(self, dwg, title, mat, fin, scale, n, N, mass, rev, date, nxt): ax = self.ax x0, y0, w, h = SW - 0.4 - 7.2, 0.4, 7.2, 2.35 ax.add_patch(Rectangle((x0, y0), w, h, fc="white", ec="k", lw=1.2, zorder=5)) def cell(x, y, cw, ch, lab, val, vs=9, bold=False): ax.add_patch(Rectangle((x, y), cw, ch, fc="none", ec="k", lw=0.6, zorder=6)) ax.text(x + 0.05, y + ch - 0.05, lab, fontsize=5.5, va="top", zorder=7) ax.text(x + 0.08, y + 0.07, val, fontsize=vs, va="bottom", zorder=7, weight="bold" if bold else "normal") cell(x0, y0 + 1.75, 4.2, 0.6, "PROJECT", "Wind tunnel - motorized 6-component sting balance", 9) cell(x0 + 4.2, y0 + 1.75, 3.0, 0.6, "DRAWN / DATE", f"Claude (AI-generated) {date}", 7.5) cell(x0, y0 + 1.05, 4.2, 0.7, "TITLE", title, 11, True) cell(x0 + 4.2, y0 + 1.05, 1.5, 0.7, "CHECKED", "", 8) cell(x0 + 5.7, y0 + 1.05, 1.5, 0.7, "APPROVED", "", 8) cell(x0, y0 + 0.5, 4.2, 0.55, "MATERIAL", mat, 8) cell(x0 + 4.2, y0 + 0.5, 3.0, 0.55, "FINISH", fin, 7.5) cell(x0, y0, 2.4, 0.5, "DWG NO.", dwg, 10, True) cell(x0 + 2.4, y0, 0.6, 0.5, "REV", rev, 10, True) cell(x0 + 3.0, y0, 0.6, 0.5, "SIZE", "B", 10) cell(x0 + 3.6, y0, 1.2, 0.5, "SCALE", scale, 9) cell(x0 + 4.8, y0, 1.2, 0.5, "WEIGHT", f"{mass:.2f} lb" if mass else "-", 8) cell(x0 + 6.0, y0, 1.2, 0.5, "SHEET", f"{n} OF {N}", 9) # tolerance block + projection symbol tx, ty, tw, th = x0 - 3.55, 0.4, 3.55, 2.35 ax.add_patch(Rectangle((tx, ty), tw, th, fc="white", ec="k", lw=1.2, zorder=5)) lines = ["UNLESS OTHERWISE SPECIFIED:", "DIMENSIONS ARE IN INCHES", "TOLERANCES:", " .X ±.03 .XX ±.010", " .XXX ±.005 .XXXX ±.0005", " ANGLES ±0°30'", "BREAK SHARP EDGES .005-.015", "SURFACE FINISH 63 µin Ra MAX", "INTERPRET PER ASME Y14.5-2018", "UNDIMENSIONED GEOMETRY PER STEP MODEL"] for i, t in enumerate(lines): ax.text(tx + 0.08, ty + th - 0.12 - i * 0.2, t, fontsize=6.6, va="top", zorder=7) px, py = tx + 2.75, ty + 0.35 # third-angle symbol ax.add_patch(Polygon([(px - 0.25, py - 0.12), (px - 0.25, py + 0.12), (px + 0.05, py + 0.2), (px + 0.05, py - 0.2)], closed=True, fc="none", ec="k", lw=0.7, zorder=7)) for r in (0.2, 0.12): ax.add_patch(matplotlib.patches.Circle((px + 0.42, py), r, fc="none", ec="k", lw=0.7, zorder=7)) ax.text(px + 0.1, py - 0.3, "THIRD ANGLE", fontsize=5, ha="center", zorder=7) if nxt: ax.text(x0 + 0.05, y0 + h + 0.08, f"NEXT ASSY: {nxt}", fontsize=7) def draw_notes(self, x=0.6, y=2.95, width_chars=80): ax = self.ax ax.text(x, y, "NOTES:", fontsize=TXT, weight="bold", va="top") yy = y - 0.22 for i, n in enumerate(self.notes, 1): words, line, first = n.split(), "", True for wd in words + [None]: if wd is None or len(line) + len(wd) + 1 > width_chars: ax.text(x + (0 if first else 0.25), yy, (f"{i}. " if first else "") + line, fontsize=7.4, va="top") yy -= 0.17 first, line = False, "" if wd is None: break line = (line + " " + wd).strip() # ------------------------------------------------------------------ annotation primitives def _txt(self, x, y, s, ha="center", va="center", rot=0, basic=False, size=None, box_fc="white"): t = self.ax.text(x, y, s, ha=ha, va=va, rotation=rot, fontsize=size or TXT, zorder=8, bbox=dict(boxstyle="square,pad=0.15", fc=box_fc, ec="k" if basic else "none", lw=0.6)) return t def _arrow(self, x0, y0, x1, y1): self.ax.annotate("", (x1, y1), (x0, y0), zorder=7, arrowprops=dict(arrowstyle="-|>,head_length=0.55,head_width=0.18", lw=0.6, color="k", shrinkA=0, shrinkB=0)) def lin(self, v, p1, p2, d="h", off=0.4, text=None, basic=False, tol=None, side=None): """Linear dimension between model points p1, p2 in view v. d='h' horizontal, 'v' vertical. off: sheet in.""" a, b = v.m(p1), v.m(p2) ax = self.ax if d == "h": yd = (a[1] if side is None else side) + off for q in (a, b): s = np.sign(yd - q[1]) or 1 ax.plot([q[0], q[0]], [q[1] + 0.05 * s, yd + 0.09 * s], "k", lw=0.45, zorder=6) mid, L = (a[0] + b[0]) / 2, abs(b[0] - a[0]) if L > 0.5: self._arrow(mid, yd, a[0], yd); self._arrow(mid, yd, b[0], yd) else: # short: arrows from outside lo, hi = sorted((a[0], b[0])) self._arrow(lo - 0.3, yd, lo, yd); self._arrow(hi + 0.3, yd, hi, yd) self._txt(mid, yd, text, basic=basic) else: xd = (a[0] if side is None else side) + off for q in (a, b): s = np.sign(xd - q[0]) or 1 ax.plot([q[0] + 0.05 * s, xd + 0.09 * s], [q[1], q[1]], "k", lw=0.45, zorder=6) mid = (a[1] + b[1]) / 2 if abs(b[1] - a[1]) > 0.5: self._arrow(xd, mid, xd, a[1]); self._arrow(xd, mid, xd, b[1]) else: lo, hi = sorted((a[1], b[1])) self._arrow(xd, lo - 0.3, xd, lo); self._arrow(xd, hi + 0.3, xd, hi) self._txt(xd, mid, text, basic=basic, rot=90) def leader(self, v, p, dx, dy, text, ha=None): a = v.m(p) tx, ty = a[0] + dx, a[1] + dy self.ax.plot([tx, tx + (0.2 if dx >= 0 else -0.2)], [ty, ty], "k", lw=0.5, zorder=6) self._arrow(tx, ty, a[0], a[1]) self.ax.text(tx + (0.25 if dx >= 0 else -0.25), ty, text, ha=ha or ("left" if dx >= 0 else "right"), va="center", fontsize=TXT, zorder=8, linespacing=1.25) return tx, ty def call(self, v, p, x, y, text, ha="left"): """Callout text at absolute sheet (x, y) with a leader + shoulder to model point p.""" a = v.m(p) sx = x - 0.12 if ha == "left" else x + 0.12 self.ax.plot([sx - (0.18 if ha == "left" else -0.18), sx], [y, y], "k", lw=0.5, zorder=6) self._arrow(sx - (0.18 if ha == "left" else -0.18), y, a[0], a[1]) self.ax.text(x, y, text, ha=ha, va="center", fontsize=TXT, zorder=8, linespacing=1.25) def datum_at(self, x, y, letter, tx, ty, triangle=True): """Datum feature symbol box at (x, y), attached to sheet point (tx, ty).""" self.ax.plot([tx, x], [ty, y], "k", lw=0.6, zorder=6) if triangle: ang = math.atan2(y - ty, x - tx) nx, ny = -math.sin(ang), math.cos(ang) self.ax.add_patch(Polygon([(tx + nx * 0.07, ty + ny * 0.07), (tx - nx * 0.07, ty - ny * 0.07), (tx + math.cos(ang) * 0.12, ty + math.sin(ang) * 0.12)], closed=True, fc="k", ec="k", zorder=7)) self.ax.add_patch(Rectangle((x - 0.13, y - 0.13), 0.26, 0.26, fc="white", ec="k", lw=0.8, zorder=8)) self.ax.text(x, y, letter, ha="center", va="center", fontsize=TXT * 1.1, weight="bold", zorder=9) def fcf(self, x, y, cells, v=None, p=None, attach="left"): """Feature control frame at sheet (x, y) (lower-left). cells: ['position', 'Ø.005Ⓜ', 'A', 'B'].""" ax = self.ax hgt, cx = 0.24, x boxes = [] for i, c in enumerate(cells): s = SYM.get(c, c) if i == 0 else c w = 0.28 if i == 0 else max(0.24, 0.085 * len(s) + 0.12) ax.add_patch(Rectangle((cx, y), w, hgt, fc="white", ec="k", lw=0.7, zorder=8)) ax.text(cx + w / 2, y + hgt / 2, s, ha="center", va="center", fontsize=TXT * (1.15 if i == 0 else 1), zorder=9) boxes.append((cx, w)) cx += w if v is not None and p is not None: a = v.m(p) sx = x if attach == "left" else cx self._arrow(sx, y + hgt / 2, a[0], a[1]) return cx def datum(self, v, p, letter, dx, dy): a = v.m(p) bx, by = a[0] + dx, a[1] + dy self.ax.plot([a[0], bx], [a[1], by], "k", lw=0.6, zorder=6) ang = math.atan2(by - a[1], bx - a[0]) nx, ny = -math.sin(ang), math.cos(ang) tri = [(a[0] + nx * 0.07, a[1] + ny * 0.07), (a[0] - nx * 0.07, a[1] - ny * 0.07), (a[0] + math.cos(ang) * 0.12, a[1] + math.sin(ang) * 0.12)] self.ax.add_patch(Polygon(tri, closed=True, fc="k", ec="k", zorder=7)) self.ax.add_patch(Rectangle((bx - 0.13, by - 0.13), 0.26, 0.26, fc="white", ec="k", lw=0.8, zorder=8)) self.ax.text(bx, by, letter, ha="center", va="center", fontsize=TXT * 1.1, weight="bold", zorder=9) def finish(self, v, p, ra, dx=0.35, dy=0.35): a = v.m(p) x, y = a[0] + dx, a[1] + dy self.ax.plot([a[0], x], [a[1], y], "k", lw=0.5) self.ax.plot([x - 0.08, x, x + 0.18, x + 0.5], [y + 0.1, y - 0.0, y + 0.3, y + 0.3], "k", lw=0.7, zorder=7) self.ax.text(x + 0.05, y + 0.33, ra, fontsize=6.8, va="bottom", zorder=8) def centerline(self, v, p1, p2, ext=0.15): a, b = v.m(p1), v.m(p2) d = (b - a) / (np.linalg.norm(b - a) + 1e-12) a, b = a - d * ext, b + d * ext self.ax.plot([a[0], b[0]], [a[1], b[1]], color="k", lw=0.4, ls=(0, (12, 3, 2, 3)), zorder=4) def cutting_plane(self, v, p1, p2, letter, arrow_dir): a, b = v.m(p1), v.m(p2) self.ax.plot([a[0], b[0]], [a[1], b[1]], "k", lw=1.0, ls=(0, (14, 3, 3, 3, 3, 3)), zorder=6) for q in (a, b): self._arrow(q[0], q[1], q[0] + arrow_dir[0] * 0.35, q[1] + arrow_dir[1] * 0.35) self.ax.text(q[0] + arrow_dir[0] * 0.5, q[1] + arrow_dir[1] * 0.5, letter, fontsize=TXT * 1.3, weight="bold", ha="center", va="center") def text(self, x, y, s, **kw): kw.setdefault("fontsize", TXT) self.ax.text(x, y, s, zorder=8, **kw) def save(self, pdf, png_path=None): pdf.savefig(self.fig) if png_path: self.fig.savefig(png_path, dpi=110) plt.close(self.fig)