hm

js/item_render_helpers.js

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+"use strict";
+
+// Shared item rendering helpers.  Field rendering stays in item_render_runtime.js.
+
+function segmentPathCacheKey(item, segments, extra = "") {
+  const version = Number(item?._mechanicalShapeVersion || 0) || 0;
+  const len = Array.isArray(segments) ? segments.length : 0;
+  let h = len * 2654435761;
+  if (Array.isArray(segments)) {
+    const step = Math.max(1, Math.floor(len / 24));
+    for (let i = 0; i < len; i += step) {
+      const seg = segments[i];
+      if (!Array.isArray(seg)) continue;
+      for (let j = 0; j < 4; j += 1) {
+        h ^= Math.round((Number(seg[j]) || 0) * 10) & 0xffff;
+        h = Math.imul(h, 16777619);
+      }
+    }
+  }
+  return `${item?.type || ""}|${version}|${len}|${h >>> 0}|${extra}`;
+}
+
+function getSegmentPath(item, segments, extra = "") {
+  if (typeof Path2D === "undefined" || !Array.isArray(segments)) return null;
+  const key = segmentPathCacheKey(item, segments, extra);
+  const cache = item._segmentRenderPathCache || (item._segmentRenderPathCache = Object.create(null));
+  if (cache.key === key && cache.path) return cache.path;
+  const path = new Path2D();
+  for (const seg of segments) {
+    if (!Array.isArray(seg) || seg.length < 4) continue;
+    path.moveTo(Number(seg[0]) || 0, Number(seg[1]) || 0);
+    path.lineTo(Number(seg[2]) || 0, Number(seg[3]) || 0);
+  }
+  cache.key = key;
+  cache.path = path;
+  return path;
+}
+
+function strokeSegments(ctx, item, segments, extra = "") {
+  const path = getSegmentPath(item, segments, extra);
+  if (path) {
+    ctx.stroke(path);
+    return;
+  }
+  ctx.beginPath();
+  for (const seg of segments || []) {
+    if (!Array.isArray(seg) || seg.length < 4) continue;
+    ctx.moveTo(Number(seg[0]) || 0, Number(seg[1]) || 0);
+    ctx.lineTo(Number(seg[2]) || 0, Number(seg[3]) || 0);
+  }
+  ctx.stroke();
+}
+
+function mechanicalRenderTier() {
+  return window.TarinaiPerf.renderQualityTier();
+}
+
+function itemShadowQualityTier() {
+  return window.TarinaiPerf?.shadowQualityTier?.() || "high";
+}
+
+function itemShadowsEnabled() {
+  return itemShadowQualityTier() !== "off";
+}
+
+function drawRopeParticlePath(ctx, particles, ox, oy) {
+  if (!Array.isArray(particles) || particles.length < 2) return false;
+  const tier = mechanicalRenderTier();
+  const stride = tier === "low" && particles.length > 10 ? 2 : 1;
+  ctx.moveTo((Number(particles[0].x) || 0) - ox, (Number(particles[0].y) || 0) - oy);
+  for (let i = stride; i < particles.length - 1; i += stride) {
+    ctx.lineTo((Number(particles[i].x) || 0) - ox, (Number(particles[i].y) || 0) - oy);
+  }
+  const last = particles[particles.length - 1];
+  ctx.lineTo((Number(last.x) || 0) - ox, (Number(last.y) || 0) - oy);
+  return true;
+}
+function drawRopeRuntimePath(ctx, particles, item, pb, ax, ay, bx, by) {
+  if (particles && drawRopeParticlePath(ctx, particles, item.x, item.y)) return true;
+  const midX = Number(pb?.linkScalar?.(item, "midX", NaN));
+  const midY = Number(pb?.linkScalar?.(item, "midY", NaN));
+  const mx = Number.isFinite(midX) ? midX - item.x : (ax + bx) * 0.5;
+  const my = Number.isFinite(midY) ? midY - item.y : (ay + by) * 0.5;
+  ctx.moveTo(ax, ay);
+  ctx.quadraticCurveTo(mx, my, bx, by);
+  return true;
+}