message: Another lightAlpha fix
diff: @@ -63,7 +63,7 @@ float lightAlpha(const uniform SciVisRenderer *uniform self,
  alpha = alpha * (1.f - material_opacity);
  if (alpha * weight < ALPHA_THRESHOLD)
  - return alpha;
  + return 0.f;
  }
  // volumes
  @@ -88,7 +88,7 @@ float lightAlpha(const uniform SciVisRenderer *uniform self,
  alpha = alpha * (1.f - material_opacity);
  if (alpha * weight < ALPHA_THRESHOLD)
  - return alpha;
  + return 0.f;
  }
  @@ -97,7 +97,7 @@ float lightAlpha(const uniform SciVisRenderer *uniform self,
  if (--remaining_depth <= 0)
  return alpha;
  - ray.t0 = org_t + rayOffset;
  + ray.t0 = org_t + self->super.epsilon;
  ray.t = org_t_max;
  ray.primID = -1;
  ray.geomID = -1;
  