Fix #107414: Cycles: [1/3] Ignore hits beyond the furthest one in embree

We should be recording only the N closest hits in case the number of
hits is exceeding the maximum allowed or the size of the hits stack.
Previously, some cases made it record hits beyond the furthest recorded
one due to lack of hit distance check.

intern/cycles/kernel/device/cpu/bvh.h

@@ -347,6 +347,9 @@ ccl_device_forceinline void kernel_embree_filter_occluded_shadow_all_func_impl(
     }
   }
 
+  /* This tells Embree to continue tracing. */
+  *args->valid = 0;
+
   /* Test if we need to record this transparent intersection. */
   const numhit_t max_record_hits = min(ctx->max_hits, numhit_t(INTEGRATOR_SHADOW_ISECT_SIZE));
   if (ctx->num_recorded_hits < max_record_hits) {
@@ -370,19 +373,21 @@ ccl_device_forceinline void kernel_embree_filter_occluded_shadow_all_func_impl(
         isect_index = max_recorded_hit;
       }
 
-      /* Limit the ray distance and stop counting hits beyond this. */
-      ray->tfar = max(current_isect.t, max_t);
+      /* Limit the ray distance and avoid processing hits beyond this. */
+      ray->tfar = max_t;
+
+      /* If it's further away than max_t, we don't record this transparent intersection. */
+      if (current_isect.t >= max_t) {
+        return;
+      }
     }
 
+    /* Always increase the number of recorded hits, even beyond the maximum,
+     * so that we can detect this and trace another ray if needed. */
+    ++ctx->num_recorded_hits;
+
     integrator_state_write_shadow_isect(ctx->isect_s, &current_isect, isect_index);
   }
-
-  /* Always increase the number of recorded hits, even beyond the maximum,
-   * so that we can detect this and trace another ray if needed. */
-  ++ctx->num_recorded_hits;
-
-  /* This tells Embree to continue tracing. */
-  *args->valid = 0;
 }
 
 ccl_device_forceinline void kernel_embree_filter_occluded_local_func_impl(