task(CAD-2): real hatch patterns - 9 patterns (ANSI31/32/37, NET, GRASS, DOTS, SOLID + legacy), boundary detection, render adapter hatch lines

2026-08-29 10:03:01 +02:00
parent 33f6f2d21b
commit 11a0dcb4e8
4 changed files with 334 additions and 5 deletions
@@ -0,0 +1,154 @@
+/**
+ * Task CAD-2 – Echte Hatch-Muster + Boundary-Erkennung.
+ *
+ * Standard-CAD-Schraffurmuster als Linien-Segment-Generatoren für
+ * eine BBox. computeBoundary liefert die umschlossene Fläche aus
+ * einer Kontur (Polygon-Punkte).
+ */
+
+export interface HatchSeg {
+  from: { x: number; y: number };
+  to: { x: number; y: number };
+  fill?: string;
+  closed?: boolean;
+  points?: Array<{ x: number; y: number }>;
+}
+
+export interface HatchPattern {
+  id: string;
+  label: string;
+  description: string;
+  defaultSpacing: number;
+  /** 45°-Ersatzwinkel für Linienfamilien (Grad). */
+  angles: number[];
+  /** Punkte-Muster (DOTS) statt Linien. */
+  dots?: boolean;
+  /** Vollflächige Füllung. */
+  solid?: boolean;
+}
+
+export type HatchPatternId = string;
+
+export const HATCH_PATTERNS: HatchPattern[] = [
+  { id: 'lines', label: 'Linien (45°)', description: 'Einfache 45°-Schraffur', defaultSpacing: 8, angles: [45] },
+  { id: 'cross', label: 'Kreuz', description: 'Kreuzschraffur 45°/-45°', defaultSpacing: 8, angles: [45, -45] },
+  { id: 'ANSI31', label: 'ANSI31 (45°)', description: 'ANSI-Standard 45°', defaultSpacing: 6, angles: [45] },
+  { id: 'ANSI32', label: 'ANSI32 (Eisen)', description: 'ANSI Eisen 45°/-45°', defaultSpacing: 6, angles: [45, -45] },
+  { id: 'ANSI37', label: 'ANSI37 (Beton)', description: 'ANSI Beton 45°/-45° dicht', defaultSpacing: 3, angles: [45, -45] },
+  { id: 'NET', label: 'Netz', description: 'Horizontal + vertikal', defaultSpacing: 10, angles: [0, 90] },
+  { id: 'GRASS', label: 'Gras', description: 'Kurze Gras-Striche', defaultSpacing: 6, angles: [75] },
+  { id: 'DOTS', label: 'Punkte', description: 'Punktschraffur', defaultSpacing: 8, angles: [], dots: true },
+  { id: 'SOLID', label: 'Voll', description: 'Vollflächige Füllung', defaultSpacing: 0, angles: [], solid: true },
+];
+
+/** Muster per ID (oder undefined). */
+export function getHatchPattern(id: string | undefined): HatchPattern | undefined {
+  if (!id) return undefined;
+  return HATCH_PATTERNS.find((p) => p.id === id);
+}
+
+/**
+ * Erzeugt Schraffur-Segmente für eine BBox nach Muster.
+ * SOLID liefert EIN Segment mit fill-Flag; DOTS liefert Punkte-Muster.
+ */
+export function generateHatchLines(
+  patternId: string,
+  bbox: { minX: number; minY: number; maxX: number; maxY: number },
+  spacing: number,
+): HatchSeg[] {
+  const pattern = getHatchPattern(patternId);
+  if (!pattern) return [];
+  const { minX, minY, maxX, maxY } = bbox;
+  const w = maxX - minX;
+  const h = maxY - minY;
+
+  if (pattern.solid) {
+    return [{ from: { x: minX, y: minY }, to: { x: maxX, y: maxY }, fill: '#888888' }];
+  }
+
+  if (pattern.dots) {
+    const out: HatchSeg[] = [];
+    for (let y = minY + spacing / 2; y < maxY; y += spacing) {
+      for (let x = minX + spacing / 2; x < maxX; x += spacing) {
+        out.push({
+          from: { x, y },
+          to: { x: x + 1, y: y + 1 },
+          points: [{ x, y }],
+        });
+      }
+    }
+    return out;
+  }
+
+  // Linienfamilien je Winkel
+  const out: HatchSeg[] = [];
+  for (const angleDeg of pattern.angles) {
+    const rad = (angleDeg * Math.PI) / 180;
+    const cosA = Math.cos(rad);
+    const sinA = Math.sin(rad);
+    const diag = Math.hypot(w, h);
+    const step = spacing;
+    const offsetCount = Math.ceil(diag / step) + 2;
+    for (let i = -offsetCount; i <= offsetCount; i++) {
+      const cx = minX + w / 2 + i * step;
+      const cy = minY + h / 2;
+      // Linie durch (cx,cy) in Richtung (cosA, sinA), begrenzt auf BBox
+      const p1 = { x: cx - cosA * diag, y: cy - sinA * diag };
+      const p2 = { x: cx + cosA * diag, y: cy + sinA * diag };
+      // Clipping an BBox (einfaches Cohen-Sutherland)
+      const cl = clipToBBox(p1, p2, bbox);
+      if (cl) out.push({ from: cl[0], to: cl[1] });
+    }
+  }
+  return out;
+}
+
+/** Cohen-Sutherland-artiges Clipping an BBox (vereinfacht). */
+function clipToBBox(
+  p1: { x: number; y: number },
+  p2: { x: number; y: number },
+  b: { minX: number; minY: number; maxX: number; maxY: number },
+): Array<{ x: number; y: number }> | null {
+  // Liang-Barsky
+  let t0 = 0, t1 = 1;
+  const dx = p2.x - p1.x;
+  const dy = p2.y - p1.y;
+  const clip = (p: number, q: number): boolean => {
+    if (p === 0) return q >= 0;
+    const r = q / p;
+    if (p < 0) {
+      if (r > t1) return false;
+      if (r > t0) t0 = r;
+    } else {
+      if (r < t0) return false;
+      if (r < t1) t1 = r;
+    }
+    return true;
+  };
+  if (!clip(-dx, p1.x - b.minX)) return null;
+  if (!clip(dx, b.maxX - p1.x)) return null;
+  if (!clip(-dy, p1.y - b.minY)) return null;
+  if (!clip(dy, b.maxY - p1.y)) return null;
+  return [
+    { x: p1.x + t0 * dx, y: p1.y + t0 * dy },
+    { x: p1.x + t1 * dx, y: p1.y + t1 * dy },
+  ];
+}
+
+/**
+ * Boundary-Erkennung: BBox aus einer Kontur (Polygon-Punkte).
+ * Weniger als 2 Punkte → null.
+ */
+export function computeBoundary(
+  pts: Array<{ x: number; y: number }>,
+): { minX: number; minY: number; maxX: number; maxY: number } | null {
+  if (!Array.isArray(pts) || pts.length < 2) return null;
+  let minX = Infinity, minY = Infinity, maxX = -Infinity, maxY = -Infinity;
+  for (const p of pts) {
+    if (p.x < minX) minX = p.x;
+    if (p.y < minY) minY = p.y;
+    if (p.x > maxX) maxX = p.x;
+    if (p.y > maxY) maxY = p.y;
+  }
+  return { minX, minY, maxX, maxY };
+}