Depth flag handling fixes (bug #7380)

Properly disable depth test while allowing depth writes to happen
Remove NiStencilProperty interaction
Don't set up depth flags for BSShaderPPLightingProperty

CHANGELOG.md

@@ -69,6 +69,7 @@
     Bug #7298: Water ripples from projectiles sometimes are not spawned
     Bug #7307: Alchemy "Magic Effect" search string does not match on tool tip for effects related to attributes
     Bug #7322: Shadows don't cover groundcover depending on the view angle and perspective with compute scene bounds = primitives
+    Bug #7380: NiZBufferProperty issue
     Bug #7413: Generated wilderness cells don't spawn fish
     Bug #7415: Unbreakable lock discrepancies
     Bug #7428: AutoCalc flag is not used to calculate enchantment costs

apps/openmw_test_suite/nifosg/testnifloader.cpp

@@ -108,7 +108,64 @@ osg::Group {
 )");
     }
 
-    std::string formatOsgNodeForShaderProperty(std::string_view shaderPrefix)
+    std::string formatOsgNodeForBSShaderProperty(std::string_view shaderPrefix)
+    {
+        std::ostringstream oss;
+        oss << R"(
+osg::Group {
+  UniqueID 1
+  DataVariance STATIC
+  UserDataContainer TRUE {
+    osg::DefaultUserDataContainer {
+      UniqueID 2
+      UDC_UserObjects 1 {
+        osg::StringValueObject {
+          UniqueID 3
+          Name "fileHash"
+        }
+      }
+    }
+  }
+  Children 1 {
+    osg::Group {
+      UniqueID 4
+      DataVariance STATIC
+      UserDataContainer TRUE {
+        osg::DefaultUserDataContainer {
+          UniqueID 5
+          UDC_UserObjects 3 {
+            osg::UIntValueObject {
+              UniqueID 6
+              Name "recIndex"
+              Value 4294967295
+            }
+            osg::StringValueObject {
+              UniqueID 7
+              Name "shaderPrefix"
+              Value ")"
+            << shaderPrefix << R"("
+            }
+            osg::BoolValueObject {
+              UniqueID 8
+              Name "shaderRequired"
+              Value TRUE
+            }
+          }
+        }
+      }
+      StateSet TRUE {
+        osg::StateSet {
+          UniqueID 9
+        }
+      }
+    }
+  }
+}
+)";
+        return oss.str();
+    }
+
+    std::string formatOsgNodeForBSLightingShaderProperty(std::string_view shaderPrefix)
     {
         std::ostringstream oss;
         oss << R"(
@@ -162,7 +219,6 @@ osg::Group {
           AttributeList 1 {
             osg::Depth {
               UniqueID 10
-              WriteMask FALSE
             }
             Value OFF
           }
@@ -204,7 +260,7 @@ osg::Group {
         Nif::NIFFile file("test.nif");
         file.mRoots.push_back(&node);
         auto result = Loader::load(file, &mImageManager);
-        EXPECT_EQ(serialize(*result), formatOsgNodeForShaderProperty(GetParam().mExpectedShaderPrefix));
+        EXPECT_EQ(serialize(*result), formatOsgNodeForBSShaderProperty(GetParam().mExpectedShaderPrefix));
     }
 
     INSTANTIATE_TEST_SUITE_P(Params, NifOsgLoaderBSShaderPrefixTest, ValuesIn(NifOsgLoaderBSShaderPrefixTest::sParams));
@@ -228,11 +284,13 @@ osg::Group {
         property.mTextureSet = nullptr;
         property.mController = nullptr;
         property.mType = GetParam().mShaderType;
+        property.mShaderFlags1 |= Nif::BSShaderFlags1::BSSFlag1_DepthTest;
+        property.mShaderFlags2 |= Nif::BSShaderFlags2::BSSFlag2_DepthWrite;
         node.mProperties.push_back(Nif::RecordPtrT<Nif::NiProperty>(&property));
         Nif::NIFFile file("test.nif");
         file.mRoots.push_back(&node);
         auto result = Loader::load(file, &mImageManager);
-        EXPECT_EQ(serialize(*result), formatOsgNodeForShaderProperty(GetParam().mExpectedShaderPrefix));
+        EXPECT_EQ(serialize(*result), formatOsgNodeForBSLightingShaderProperty(GetParam().mExpectedShaderPrefix));
     }
 
     INSTANTIATE_TEST_SUITE_P(

components/nifosg/nifloader.cpp

@@ -1964,11 +1964,17 @@ namespace NifOsg
             return texEnv;
         }
 
-        void handleDepthFlags(osg::StateSet* stateset, bool depthTest, bool depthWrite,
+        void handleDepthFlags(osg::StateSet* stateset, bool depthTest, bool depthWrite)
-            osg::Depth::Function depthFunction = osg::Depth::LESS)
         {
-            stateset->setMode(GL_DEPTH_TEST, depthTest ? osg::StateAttribute::ON : osg::StateAttribute::OFF);
+            if (!depthWrite && !depthTest)
-            osg::ref_ptr<osg::Depth> depth = new osg::Depth(depthFunction, 0.0, 1.0, depthWrite);
+            {
+                stateset->setMode(GL_DEPTH_TEST, osg::StateAttribute::OFF);
+                return;
+            }
+            osg::ref_ptr<osg::Depth> depth = new osg::Depth;
+            depth->setWriteMask(depthWrite);
+            if (!depthTest)
+                depth->setFunction(osg::Depth::ALWAYS);
             depth = shareAttribute(depth);
             stateset->setAttributeAndModes(depth, osg::StateAttribute::ON);
         }
@@ -2328,10 +2334,8 @@ namespace NifOsg
                 {
                     const Nif::NiZBufferProperty* zprop = static_cast<const Nif::NiZBufferProperty*>(property);
                     osg::StateSet* stateset = node->getOrCreateStateSet();
-                    // Morrowind ignores depth test function, unless a NiStencilProperty is present, in which case it
+                    // The test function from this property seems to be ignored.
-                    // uses a fixed depth function of GL_ALWAYS.
+                    handleDepthFlags(stateset, zprop->depthTest(), zprop->depthWrite());
-                    osg::Depth::Function depthFunction = hasStencilProperty ? osg::Depth::ALWAYS : osg::Depth::LESS;
-                    handleDepthFlags(stateset, zprop->depthTest(), zprop->depthWrite(), depthFunction);
                     break;
                 }
                 // OSG groups the material properties that NIFs have separate, so we have to parse them all again when
@@ -2370,7 +2374,6 @@ namespace NifOsg
                             textureSet, texprop->mClamp, node->getName(), stateset, imageManager, boundTextures);
                     }
                     handleTextureControllers(texprop, composite, imageManager, stateset, animflags);
-                    handleDepthFlags(stateset, texprop->depthTest(), texprop->depthWrite());
                     break;
                 }
                 case Nif::RC_BSShaderNoLightingProperty: