Wall drags at 45° lay slopes; diagonal tubes drawn as one pipe; no side arrow on drag ghosts (t35, t36)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/render/smooth-shaders.js

@@ -252,8 +252,10 @@ void main() {
     float a = (vert ? fract(w.x * 0.25) : fract(w.y * 0.25)) * 4.0, along = vert ? w.y : w.x;
     if (nc >= 19) {
       vec2 d = nc == 19 ? vec2(1.0, -1.0) : nc == 20 ? vec2(1.0, 1.0) : nc == 21 ? vec2(-1.0, 1.0) : vec2(-1.0, -1.0);
-      a = fract(dot(w, vec2(-d.y, d.x)) * 0.25) * 4.0;
-      along = dot(w, d); sp2 = 1.0;
+      float offset = cellAt(tTree, c).r * 255.0 - 128.0;
+      bool rising = nc == 19 || nc == 21;
+      a = 2.0 + (offset + dot(fract(w) - 0.5, vec2(1.0, rising ? 1.0 : -1.0))) * 0.70710678;
+      along = dot(w, d) * 0.70710678; sp2 = 1.0;
     }
     float wall = 0.62;
     vec3 tc;
@@ -263,7 +265,7 @@ void main() {
       tc = vec3(0.62, 0.41, 0.27) * (0.6 + 0.55 * cyl);
       if (a < wall) tc *= 1.08;
       float ring = 1.0 - smoothstep(0.0, 0.3, min(fract(along * 0.25), 1.0 - fract(along * 0.25)) * 4.0);
-      tc *= 1.0 - 0.3 * ring;
+      if (nc < 19) tc *= 1.0 - 0.3 * ring;
       tc *= mix(0.5, 1.0, smoothstep(0.0, max(px * 1.3, 0.1), min(a, 4.0 - a)));
     } else {
       bool full = own.r + own.g + own.b > 0.0;
@@ -274,7 +276,11 @@ void main() {
       tc = mix(tc, vec3(0.6, 0.48, 0.38), flight * (full ? 0.35 : 0.8));
       tc *= 1.0 - 0.25 * smoothstep(0.9, 1.3, abs(a - 2.0));
     }
-    C = tc;
+    if (nc >= 19) {
+      bool full = own.r + own.g + own.b > 0.0;
+      if (full) C = mix(C, own.rgb, 1.0 - smoothstep(0.36, 0.5, length(fract(w) - 0.5)));
+      C = mix(C, tc, 1.0 - smoothstep(2.0 - px, 2.0 + px, abs(a - 2.0)));
+    } else C = tc;
   }
   else if (nc == 6 || (nc >= 15 && nc <= 18)) {
     vec2 lb = fract(w * 0.25) * 4.0, rb = 4.0 - lb;