w.i.p

src/prim-types.hh

@@ -1680,7 +1680,31 @@ class TypedAttributeWithFallback {
 
   void set_value_empty() { _empty = true; }
 
-  bool is_value_empty() const { return _empty; }
+  bool has_connections() const { return _paths.size(); }
+
+  bool is_value_empty() const {
+    if (has_connections()) {
+      return false;
+    }
+
+    if (_empty) {
+      return true;
+    }
+
+    if (_attrib) {
+      return false;
+    }
+
+    return true;
+  }
+
+  bool has_value() const {
+    if (_empty) {
+      return false;
+    }
+
+    return true;
+  }
 
   const T &get_value() const {
     if (_attrib) {
@@ -1694,7 +1718,7 @@ class TypedAttributeWithFallback {
   // for `uniform` attribute only
   void set_blocked(bool onoff) { _blocked = onoff; }
 
-  bool is_connection() const { return _paths.size(); }
+  bool is_connection() const { return _paths.size() && !has_value() ; }
 
   void set_connection(const Path &path) {
     _paths.clear();
@@ -1714,6 +1738,8 @@ class TypedAttributeWithFallback {
     return nonstd::nullopt;
   }
 
+  void clear_connections() { _paths.clear(); }
+
   // value set?
   bool authored() const {
     if (_empty) {  // authored with empty value.

src/tydra/attribute-eval-typed-animatable-fallback.cc

@@ -28,7 +28,9 @@ bool EvaluateTypedAttributeImpl(
     const double t, const value::TimeSampleInterpolationType tinterp)
 {
 
-  if (attr.is_connection()) {
+  if (attr.has_value()) {
+    return attr.get_value(value);
+  } if (attr.has_connections()) {
     // Follow connection target Path(singple targetPath only).
     std::vector<Path> pv = attr.connections();
     if (pv.empty()) {
@@ -81,8 +83,8 @@ bool EvaluateTypedAttributeImpl(
       PUSH_ERROR_AND_RETURN(
           fmt::format("Attribute `{}` is ValueBlocked(None).", attr_name));
   } else {
-
-    return attr.get_value(value);
+      PUSH_ERROR_AND_RETURN(
+          fmt::format("Internal error. Invalid TypedAttributeWithFallback<Animatable<{}>>.", value::TypeTraits<T>::type_name()));
 
   }
 
@@ -140,12 +142,23 @@ bool EvaluateTypedAnimatableAttribute(
       (*err) += "Attribute is Blocked.\n";
     }
     return false;
+  } else if (tattr.has_value()) {
+    const Animatable<T> &value = tattr.get_value();
+    T v;
+    if (value.get(t, &v, tinterp)) {
+      return true;
+    } else {
+      if (err) {
+        (*err) += fmt::format("Failed to get TypedAnimatableAttribute value: {} \n", attr_name);
+      }
+      return false;
+    }
   } else if (tattr.is_value_empty()) {
     if (err) {
       (*err) += "Attribute value is empty.\n";
     }
     return false;
-  } else if (tattr.is_connection()) {
+  } else if (tattr.has_connections()) {
 
     // Follow targetPath
     Attribute attr = ToAttributeConnection(tattr);
@@ -170,16 +183,6 @@ bool EvaluateTypedAnimatableAttribute(
     }
 
   } else {
-    const Animatable<T> &value = tattr.get_value();
-    T v;
-    if (value.get(t, &v, tinterp)) {
-      return true;
-    } else {
-      if (err) {
-        (*err) += fmt::format("Failed to get TypedAnimatableAttribute value: {} \n", attr_name);
-      }
-      return false;
-    }
 
     if (err) {
       (*err) += fmt::format("[Internal error] Invalid TypedAttribute? : {} \n", attr_name);

src/tydra/attribute-eval-typed-animatable.cc

@@ -28,7 +28,11 @@ bool EvaluateTypedAttributeImpl(
     const double t, const value::TimeSampleInterpolationType tinterp)
 {
 
-  if (attr.is_connection()) {
+  if (attr.has_value()) {
+
+    return attr.get_value(value);
+
+  } else if (attr.has_connection()) {
     // Follow connection target Path(singple targetPath only).
     std::vector<Path> pv = attr.connections();
     if (pv.empty()) {
@@ -82,7 +86,7 @@ bool EvaluateTypedAttributeImpl(
           fmt::format("Attribute `{}` is ValueBlocked(None).", attr_name));
   } else {
 
-    return attr.get_value(value);
+    PUSH_ERROR_AND_RETURN("Internal error. Invalid TypedAttribute<Animatable<T>> value.");
 
   }
 

src/tydra/attribute-eval-typed-fallback.cc

@@ -31,7 +31,10 @@ bool EvaluateTypedAttributeImpl(
     const double t, const value::TimeSampleInterpolationType tinterp)
 {
 
-  if (attr.is_connection()) {
+  if (attr.has_value()) {
+    return attr.get_value(value);
+
+  } else if (attr.has_connection()) {
     // Follow connection target Path(singple targetPath only).
     std::vector<Path> pv = attr.connections();
     if (pv.empty()) {
@@ -84,8 +87,8 @@ bool EvaluateTypedAttributeImpl(
       PUSH_ERROR_AND_RETURN(
           fmt::format("Attribute `{}` is ValueBlocked(None).", attr_name));
   } else {
-
-    return attr.get_value(value);
+      PUSH_ERROR_AND_RETURN(
+          fmt::format("Internal error. Attribute `{}` has invalid form of TypedAttributeWithFallback<{}>.", attr_name, value::TypeTraits<T>::type_name()));
 
   }
 
@@ -141,12 +144,15 @@ bool EvaluateTypedAttribute(
       (*err) += "Attribute is Blocked.\n";
     }
     return false;
+  } else if (tattr.has_value()) {
+    (*value_out) = tattr.get_value();
+    return true;
   } else if (tattr.is_value_empty()) {
     if (err) {
       (*err) += "Attribute value is empty.\n";
     }
     return false;
-  } else if (tattr.is_connection()) {
+  } else if (tattr.has_connections()) {
 
     // Follow targetPath 
     Attribute attr = ToAttributeConnection(tattr);
@@ -170,11 +176,11 @@ bool EvaluateTypedAttribute(
       (*err) += fmt::format("Type mismatch. Value producing attribute has type {}, but requested type is {}. Attribute: {}", value.type_name(), tattr.type_name(), attr_name);
     }
 
-  } else {
-    (*value_out) = tattr.get_value();
-    return true;
   }
-  return false;
+
+  PUSH_ERROR_AND_RETURN(fmt::format("Internal error. Attribute {} has invalid form of TypedAttributeWithFallback<{}>.",
+     attr_name, value::TypeTraits<T>::type_name()));
+
 }
 
 // template instanciations

tests/usda/multi-attribute-004.usda

@@ -0,0 +1,7 @@
+#usda 1.0
+
+def "bora" {
+  float val = 100.5 ( elementSize = 2 )
+  float val.timeSamples = {0: 1.0, 2: 2.0, 3: 3.0} 
+  #float val.connect = </bora.value> 
+}