From 3b62e203f754717c49ea256c425642801d251759 Mon Sep 17 00:00:00 2001
From: Zach Pomerantz <zach@highfidelity.io>
Date: Fri, 11 Mar 2016 14:25:21 -0800
Subject: [PATCH] Cache NetworkGeometry::_hasTransparentTextures

---
 .../model-networking/src/model-networking/ModelCache.cpp    | 6 +++++-
 .../model-networking/src/model-networking/ModelCache.h      | 5 +++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/libraries/model-networking/src/model-networking/ModelCache.cpp b/libraries/model-networking/src/model-networking/ModelCache.cpp
index 29c517594a..af9fe97e93 100644
--- a/libraries/model-networking/src/model-networking/ModelCache.cpp
+++ b/libraries/model-networking/src/model-networking/ModelCache.cpp
@@ -135,6 +135,8 @@ bool NetworkGeometry::isLoadedWithTextures() const {
     }
 
     if (!_isLoadedWithTextures) {
+        _hasTransparentTextures = false;
+
         for (auto&& material : _materials) {
             if ((material->albedoTexture && !material->albedoTexture->isLoaded()) ||
                 (material->normalTexture && !material->normalTexture->isLoaded()) ||
@@ -148,7 +150,9 @@ bool NetworkGeometry::isLoadedWithTextures() const {
             if (material->albedoTexture) {
                 // Reset the materialKey transparentTexture key only, as it is albedoTexture-dependent
                 const auto& usage = material->albedoTexture->getGPUTexture()->getUsage();
-                material->_material->setTransparentTexture(usage.isAlpha() && !usage.isAlphaMask());
+                bool isTransparentTexture = usage.isAlpha() && !usage.isAlphaMask();
+                material->_material->setTransparentTexture(isTransparentTexture);
+                _hasTransparentTextures = _hasTransparentTextures || isTransparentTexture;
             }
         }
 
diff --git a/libraries/model-networking/src/model-networking/ModelCache.h b/libraries/model-networking/src/model-networking/ModelCache.h
index 60f185f691..7f01bdafaa 100644
--- a/libraries/model-networking/src/model-networking/ModelCache.h
+++ b/libraries/model-networking/src/model-networking/ModelCache.h
@@ -75,6 +75,10 @@ public:
     // true when the requested geometry and its textures are loaded.
     bool isLoadedWithTextures() const;
 
+    // true if the albedo texture has a non-masking alpha channel.
+    // This can only be known after isLoadedWithTextures().
+    bool hasTransparentTextures() const { return _hasTransparentTextures; }
+
     // WARNING: only valid when isLoaded returns true.
     const FBXGeometry& getFBXGeometry() const { return *_geometry; }
     const std::vector<std::unique_ptr<NetworkMesh>>& getMeshes() const { return _meshes; }
@@ -151,6 +155,7 @@ protected:
 
     // cache for isLoadedWithTextures()
     mutable bool _isLoadedWithTextures = false;
+    mutable bool _hasTransparentTextures = false;
 };
 
 /// Reads geometry in a worker thread.