From db255233f758821a96bba012b2141c12dc2f9f51 Mon Sep 17 00:00:00 2001
From: Julian Smith <jules@op59.net>
Date: Tue, 3 Mar 2020 00:07:08 +0000
Subject: [PATCH] src/Viewer/ViewPropertyEvaluator.*: added getBoolValue().

---
 src/Viewer/ViewPropertyEvaluator.cxx | 22 ++++++++++++++++++++++
 src/Viewer/ViewPropertyEvaluator.hxx |  3 +++
 2 files changed, 25 insertions(+)

diff --git a/src/Viewer/ViewPropertyEvaluator.cxx b/src/Viewer/ViewPropertyEvaluator.cxx
index f9703e7cd..8c980dd7a 100644
--- a/src/Viewer/ViewPropertyEvaluator.cxx
+++ b/src/Viewer/ViewPropertyEvaluator.cxx
@@ -498,6 +498,17 @@ namespace ViewPropertyEvaluator {
         return default_;
     }
 
+    bool getSequenceBoolValue(Sequence& sequence, bool default_)
+    {
+        SGPropertyNode* node = getSequenceNode(sequence);
+        if (node) {
+            if (node->getStringValue()[0] != 0) {
+                return node->getBoolValue();
+            }
+        }
+        return default_;
+    }
+
     const std::string& getStringValue(const char* spec)
     {
         std::shared_ptr<Sequence>   sequence = getSequence(spec);
@@ -515,6 +526,17 @@ namespace ViewPropertyEvaluator {
         return ret;
     }
 
+    bool getBoolValue(const char* spec, bool default_)
+    {
+        std::shared_ptr<Sequence>   sequence = getSequence(spec);
+        if (sequence->_nodes.size() != 1 || sequence->_nodes.front()->_begin[0] != '(') {
+            SG_LOG(SG_VIEW, SG_DEBUG,  "bad sequence for getBoolValue() - must have outermost '(...)': '" << spec);
+            abort();
+        }
+        bool ret = getSequenceBoolValue(*sequence, default_);
+        return ret;
+    }
+
     std::ostream& operator << (std::ostream& out, const Dump& dump)
     {
         out << "ViewPropertyEvaluator\n";
diff --git a/src/Viewer/ViewPropertyEvaluator.hxx b/src/Viewer/ViewPropertyEvaluator.hxx
index 4779feba6..66be22d92 100644
--- a/src/Viewer/ViewPropertyEvaluator.hxx
+++ b/src/Viewer/ViewPropertyEvaluator.hxx
@@ -106,6 +106,9 @@ namespace ViewPropertyEvaluator {
     node, instead it always calls <top-level-node>->getDoubleValue().
     */
     double getDoubleValue(const char* spec, double default_=0);
+
+    /* Similar to getDoubleValue(). */
+    bool getBoolValue(const char* spec, bool default_=false);
     
     
     /* Outputs detailed information about all specs that have been seen.