diff --git a/hecl/extern/boo b/hecl/extern/boo
index 73891af56..05c26a535 160000
--- a/hecl/extern/boo
+++ b/hecl/extern/boo
@@ -1 +1 @@
-Subproject commit 73891af56a633cf2b4e047b6422f34c80230eb29
+Subproject commit 05c26a535b23b1b787523e896853c3641cb888c8
diff --git a/hecl/include/hecl/Backend/Backend.hpp b/hecl/include/hecl/Backend/Backend.hpp
index 7052c3f5f..fddcb816e 100644
--- a/hecl/include/hecl/Backend/Backend.hpp
+++ b/hecl/include/hecl/Backend/Backend.hpp
@@ -13,14 +13,14 @@ using Diagnostics = Frontend::Diagnostics;
 using SourceLocation = Frontend::SourceLocation;
 using ArithmeticOp = IR::Instruction::ArithmeticOpType;
 
-enum class TexGenSrc
+enum class TexGenSrc : uint8_t
 {
     Position,
     Normal,
     UV
 };
 
-enum class BlendFactor
+enum class BlendFactor : uint8_t
 {
     Zero,
     One,
@@ -37,6 +37,15 @@ enum class BlendFactor
     Original = 0xff
 };
 
+enum class ZTest : uint8_t
+{
+    None,
+    LEqual,
+    Greater,
+    Equal,
+    Original = 0xff
+};
+
 struct TextureInfo
 {
     TexGenSrc src;
diff --git a/hecl/include/hecl/Runtime.hpp b/hecl/include/hecl/Runtime.hpp
index 563367305..d034eb0f7 100644
--- a/hecl/include/hecl/Runtime.hpp
+++ b/hecl/include/hecl/Runtime.hpp
@@ -135,6 +135,11 @@ public:
         const Backend::TextureInfo* texs = nullptr;
         Backend::BlendFactor srcFactor = Backend::BlendFactor::Original;
         Backend::BlendFactor dstFactor = Backend::BlendFactor::Original;
+        Backend::ZTest depthTest = Backend::ZTest::Original;
+        bool frontfaceCull = false;
+        bool noDepthWrite = false;
+        bool noColorWrite = false;
+        bool noAlphaWrite = false;
     };
     std::vector<ExtensionSlot> m_extensionSlots;
 
@@ -149,7 +154,12 @@ public:
     unsigned registerExtensionSlot(Function lighting, Function post,
                                    size_t blockCount, const char** blockNames,
                                    size_t texCount, const Backend::TextureInfo* texs,
-                                   Backend::BlendFactor srcFactor, Backend::BlendFactor dstFactor)
+                                   Backend::BlendFactor srcFactor, Backend::BlendFactor dstFactor,
+                                   Backend::ZTest depthTest = Backend::ZTest::Original,
+                                   bool frontfaceCull = false,
+                                   bool noDepthWrite = false,
+                                   bool noColorWrite = false,
+                                   bool noAlphaWrite = false)
     {
         m_extensionSlots.emplace_back();
         ExtensionSlot& slot = m_extensionSlots.back();
@@ -161,6 +171,11 @@ public:
         slot.texs = texs;
         slot.srcFactor = srcFactor;
         slot.dstFactor = dstFactor;
+        slot.depthTest = depthTest;
+        slot.frontfaceCull = frontfaceCull;
+        slot.noDepthWrite = noDepthWrite;
+        slot.noColorWrite = noColorWrite;
+        slot.noAlphaWrite = noAlphaWrite;
         return m_extensionSlots.size() - 1;
     }
 };
@@ -286,7 +301,8 @@ struct HMDLData
                                                  const boo::PipelineStage* ubufStages,
                                                  size_t texCount, boo::ITexture** texs)
     {return ctx.newShaderDataBinding(shader, m_vtxFmt, m_vbo, nullptr, m_ibo,
-                                     ubufCount, ubufs, ubufStages, nullptr, nullptr, texCount, texs);}
+                                     ubufCount, ubufs, ubufStages, nullptr, nullptr,
+                                     texCount, texs, nullptr, nullptr);}
 };
 
 }
diff --git a/hecl/lib/Backend/GLSL.cpp b/hecl/lib/Backend/GLSL.cpp
index 58c7e35db..66ab91db0 100644
--- a/hecl/lib/Backend/GLSL.cpp
+++ b/hecl/lib/Backend/GLSL.cpp
@@ -361,8 +361,8 @@ struct GLSLBackendFactory : IShaderBackendFactory
                                   2, STD_BLOCKNAMES,
                                   boo::BlendFactor(m_backend.m_blendSrc),
                                   boo::BlendFactor(m_backend.m_blendDst),
-                                  tag.getPrimType(), tag.getDepthTest(),
-                                  tag.getDepthWrite(),
+                                  tag.getPrimType(), tag.getDepthTest() ? boo::ZTest::LEqual : boo::ZTest::None,
+                                  tag.getDepthWrite(), true, false,
                                   tag.getBackfaceCulling() ? boo::CullMode::Backface : boo::CullMode::None);
         if (!objOut)
             Log.report(logvisor::Fatal, "unable to build shader");
@@ -401,7 +401,8 @@ struct GLSLBackendFactory : IShaderBackendFactory
                                   texMapEnd, STD_TEXNAMES,
                                   2, STD_BLOCKNAMES,
                                   blendSrc, blendDst, tag.getPrimType(),
-                                  tag.getDepthTest(), tag.getDepthWrite(),
+                                  tag.getDepthTest() ? boo::ZTest::LEqual : boo::ZTest::None,
+                                  tag.getDepthWrite(), true, false,
                                   tag.getBackfaceCulling() ? boo::CullMode::Backface : boo::CullMode::None);
         if (!ret)
             Log.report(logvisor::Fatal, "unable to build shader");
@@ -442,15 +443,37 @@ struct GLSLBackendFactory : IShaderBackendFactory
                                                     slot.lighting, slot.post, slot.texCount, slot.texs));
             cachedSz += sources.back().first.size() + 1;
             cachedSz += sources.back().second.size() + 1;
+
+            boo::ZTest zTest;
+            switch (slot.depthTest)
+            {
+            case hecl::Backend::ZTest::Original:
+            default:
+                zTest = tag.getDepthTest() ? boo::ZTest::LEqual : boo::ZTest::None;
+                break;
+            case hecl::Backend::ZTest::None:
+                zTest = boo::ZTest::None;
+                break;
+            case hecl::Backend::ZTest::LEqual:
+                zTest = boo::ZTest::LEqual;
+                break;
+            case hecl::Backend::ZTest::Greater:
+                zTest = boo::ZTest::Greater;
+                break;
+            case hecl::Backend::ZTest::Equal:
+                zTest = boo::ZTest::Equal;
+                break;
+            }
+
             boo::IShaderPipeline* ret =
             static_cast<boo::GLDataFactory::Context&>(ctx).
                     newShaderPipeline(sources.back().first.c_str(), sources.back().second.c_str(),
                                       8, STD_TEXNAMES, bc, bn,
                                       boo::BlendFactor((slot.srcFactor == hecl::Backend::BlendFactor::Original) ? m_backend.m_blendSrc : slot.srcFactor),
                                       boo::BlendFactor((slot.dstFactor == hecl::Backend::BlendFactor::Original) ? m_backend.m_blendDst : slot.dstFactor),
-                                      tag.getPrimType(), tag.getDepthTest(),
-                                      tag.getDepthWrite(),
-                                      tag.getBackfaceCulling() ? boo::CullMode::Backface : boo::CullMode::None);
+                                      tag.getPrimType(), zTest, slot.noDepthWrite ? false : tag.getDepthWrite(), !slot.noColorWrite, !slot.noAlphaWrite,
+                                      slot.frontfaceCull ? boo::CullMode::Frontface :
+                                      (tag.getBackfaceCulling() ? boo::CullMode::Backface : boo::CullMode::None));
             if (!ret)
                 Log.report(logvisor::Fatal, "unable to build shader");
             returnFunc(ret);
@@ -503,14 +526,36 @@ struct GLSLBackendFactory : IShaderBackendFactory
             if (r.hasError())
                 return false;
 
+            boo::ZTest zTest;
+            switch (slot.depthTest)
+            {
+            case hecl::Backend::ZTest::Original:
+            default:
+                zTest = tag.getDepthTest() ? boo::ZTest::LEqual : boo::ZTest::None;
+                break;
+            case hecl::Backend::ZTest::None:
+                zTest = boo::ZTest::None;
+                break;
+            case hecl::Backend::ZTest::LEqual:
+                zTest = boo::ZTest::LEqual;
+                break;
+            case hecl::Backend::ZTest::Greater:
+                zTest = boo::ZTest::Greater;
+                break;
+            case hecl::Backend::ZTest::Equal:
+                zTest = boo::ZTest::Equal;
+                break;
+            }
+
             boo::IShaderPipeline* ret =
             static_cast<boo::GLDataFactory::Context&>(ctx).
                     newShaderPipeline(vertSource.c_str(), fragSource.c_str(),
                                       8, STD_TEXNAMES, bc, bn,
                                       boo::BlendFactor((slot.srcFactor == hecl::Backend::BlendFactor::Original) ? blendSrc : slot.srcFactor),
                                       boo::BlendFactor((slot.dstFactor == hecl::Backend::BlendFactor::Original) ? blendDst : slot.dstFactor),
-                                      tag.getPrimType(), tag.getDepthTest(), tag.getDepthWrite(),
-                                      tag.getBackfaceCulling() ? boo::CullMode::Backface : boo::CullMode::None);
+                                      tag.getPrimType(), zTest, slot.noDepthWrite ? false : tag.getDepthWrite(), !slot.noColorWrite, !slot.noAlphaWrite,
+                                      slot.frontfaceCull ? boo::CullMode::Frontface :
+                                      (tag.getBackfaceCulling() ? boo::CullMode::Backface : boo::CullMode::None));
             if (!ret)
                 Log.report(logvisor::Fatal, "unable to build shader");
             returnFunc(ret);
@@ -681,7 +726,8 @@ struct SPIRVBackendFactory : IShaderBackendFactory
                                                            m_backend.m_blendSrc : slot.srcFactor),
                                       boo::BlendFactor((slot.dstFactor == hecl::Backend::BlendFactor::Original) ?
                                                            m_backend.m_blendDst : slot.dstFactor),
-                                      tag.getPrimType(), tag.getDepthTest(), tag.getDepthWrite(),
+                                      tag.getPrimType(), tag.getDepthTest(), slot.noDepthWrite ? false : tag.getDepthWrite(),
+                                      !slot.noColorWrite, !slot.noAlphaWrite,
                                       tag.getBackfaceCulling() ? boo::CullMode::Backface : boo::CullMode::None);
             if (!ret)
                 Log.report(logvisor::Fatal, "unable to build shader");
@@ -772,7 +818,8 @@ struct SPIRVBackendFactory : IShaderBackendFactory
                                       tag.newVertexFormat(ctx),
                                       boo::BlendFactor((slot.srcFactor == hecl::Backend::BlendFactor::Original) ? blendSrc : slot.srcFactor),
                                       boo::BlendFactor((slot.dstFactor == hecl::Backend::BlendFactor::Original) ? blendDst : slot.dstFactor),
-                                      tag.getPrimType(), tag.getDepthTest(), tag.getDepthWrite(),
+                                      tag.getPrimType(), tag.getDepthTest(), slot.noDepthWrite ? false : tag.getDepthWrite(),
+                                      !slot.noColorWrite, !slot.noAlphaWrite,
                                       tag.getBackfaceCulling() ? boo::CullMode::Backface : boo::CullMode::None);
             if (!ret)
                 Log.report(logvisor::Fatal, "unable to build shader");
diff --git a/hecl/lib/Backend/HLSL.cpp b/hecl/lib/Backend/HLSL.cpp
index b6b904780..ff067ba48 100644
--- a/hecl/lib/Backend/HLSL.cpp
+++ b/hecl/lib/Backend/HLSL.cpp
@@ -451,6 +451,28 @@ struct HLSLBackendFactory : IShaderBackendFactory
                                                         slot.lighting, slot.post, slot.texCount, slot.texs);
             pipeBlobs.emplace_back();
             Blobs& thisPipeBlobs = pipeBlobs.back();
+
+            boo::ZTest zTest;
+            switch (slot.depthTest)
+            {
+            case hecl::Backend::ZTest::Original:
+            default:
+                zTest = tag.getDepthTest() ? boo::ZTest::LEqual : boo::ZTest::None;
+                break;
+            case hecl::Backend::ZTest::None:
+                zTest = boo::ZTest::None;
+                break;
+            case hecl::Backend::ZTest::LEqual:
+                zTest = boo::ZTest::LEqual;
+                break;
+            case hecl::Backend::ZTest::Greater:
+                zTest = boo::ZTest::Greater;
+                break;
+            case hecl::Backend::ZTest::Equal:
+                zTest = boo::ZTest::Equal;
+                break;
+            }
+
             boo::IShaderPipeline* ret =
             static_cast<boo::ID3DDataFactory::Context&>(ctx).
                 newShaderPipeline(vertSource.c_str(), fragSource.c_str(),
@@ -458,9 +480,9 @@ struct HLSLBackendFactory : IShaderBackendFactory
                                   tag.newVertexFormat(ctx),
                                   boo::BlendFactor((slot.srcFactor == hecl::Backend::BlendFactor::Original) ? m_backend.m_blendSrc : slot.srcFactor),
                                   boo::BlendFactor((slot.dstFactor == hecl::Backend::BlendFactor::Original) ? m_backend.m_blendDst : slot.dstFactor),
-                                  tag.getPrimType(),
-                                  tag.getDepthTest(), tag.getDepthWrite(),
-                                  tag.getBackfaceCulling() ? boo::CullMode::Backface : boo::CullMode::None);
+                                  tag.getPrimType(), zTest, slot.noDepthWrite ? false : tag.getDepthWrite(),
+                                  slot.frontfaceCull ? boo::CullMode::Frontface :
+                                  (tag.getBackfaceCulling() ? boo::CullMode::Backface : boo::CullMode::None));
             if (!ret)
                 Log.report(logvisor::Fatal, "unable to build shader");
             if (thisPipeBlobs.vert)
@@ -549,6 +571,27 @@ struct HLSLBackendFactory : IShaderBackendFactory
             if (r.hasError())
                 return false;
 
+            boo::ZTest zTest;
+            switch (slot.depthTest)
+            {
+            case hecl::Backend::ZTest::Original:
+            default:
+                zTest = tag.getDepthTest() ? boo::ZTest::LEqual : boo::ZTest::None;
+                break;
+            case hecl::Backend::ZTest::None:
+                zTest = boo::ZTest::None;
+                break;
+            case hecl::Backend::ZTest::LEqual:
+                zTest = boo::ZTest::LEqual;
+                break;
+            case hecl::Backend::ZTest::Greater:
+                zTest = boo::ZTest::Greater;
+                break;
+            case hecl::Backend::ZTest::Equal:
+                zTest = boo::ZTest::Equal;
+                break;
+            }
+
             boo::IShaderPipeline* ret =
             static_cast<boo::ID3DDataFactory::Context&>(ctx).
                 newShaderPipeline(nullptr, nullptr,
@@ -556,9 +599,9 @@ struct HLSLBackendFactory : IShaderBackendFactory
                                   tag.newVertexFormat(ctx),
                                   boo::BlendFactor((slot.srcFactor == hecl::Backend::BlendFactor::Original) ? blendSrc : slot.srcFactor),
                                   boo::BlendFactor((slot.dstFactor == hecl::Backend::BlendFactor::Original) ? blendDst : slot.dstFactor),
-                                  tag.getPrimType(),
-                                  tag.getDepthTest(), tag.getDepthWrite(),
-                                  tag.getBackfaceCulling() ? boo::CullMode::Backface : boo::CullMode::None);
+                                  tag.getPrimType(), zTest, slot.noDepthWrite ? false : tag.getDepthWrite(),
+                                  slot.frontfaceCull ? boo::CullMode::Frontface :
+                                  (tag.getBackfaceCulling() ? boo::CullMode::Backface : boo::CullMode::None));
             if (!ret)
                 Log.report(logvisor::Fatal, "unable to build shader");
             returnFunc(ret);
diff --git a/hecl/lib/Backend/Metal.cpp b/hecl/lib/Backend/Metal.cpp
index a6300aa3d..f18abd1d4 100644
--- a/hecl/lib/Backend/Metal.cpp
+++ b/hecl/lib/Backend/Metal.cpp
@@ -66,7 +66,7 @@ std::string Metal::GenerateVertInStruct(unsigned col, unsigned uv, unsigned w) c
     if (w)
     {
         for (unsigned i=0 ; i<w ; ++i, ++idx)
-        retval += hecl::Format("    float4 weightIn%u [[ attribute(%u) ]];\n", i, idx);
+            retval += hecl::Format("    float4 weightIn%u [[ attribute(%u) ]];\n", i, idx);
     }
 
     return retval + "};\n";
@@ -407,7 +407,7 @@ struct MetalBackendFactory : IShaderBackendFactory
                               boo::BlendFactor(m_backend.m_blendSrc),
                               boo::BlendFactor(m_backend.m_blendDst),
                               tag.getPrimType(),
-                              tag.getDepthTest(), tag.getDepthWrite(),
+                              tag.getDepthTest() ? boo::ZTest::LEqual : boo::ZTest::None, tag.getDepthWrite(), true, true,
                               tag.getBackfaceCulling() ? boo::CullMode::Backface : boo::CullMode::None);
         if (!objOut)
             Log.report(logvisor::Fatal, "unable to build shader");
@@ -444,7 +444,7 @@ struct MetalBackendFactory : IShaderBackendFactory
             newShaderPipeline(vertSource.c_str(), fragSource.c_str(),
                               tag.newVertexFormat(ctx), m_rtHint,
                               blendSrc, blendDst, tag.getPrimType(),
-                              tag.getDepthTest(), tag.getDepthWrite(),
+                              tag.getDepthTest() ? boo::ZTest::LEqual : boo::ZTest::None, tag.getDepthWrite(), true, true,
                               tag.getBackfaceCulling() ? boo::CullMode::Backface : boo::CullMode::None);
         if (!ret)
             Log.report(logvisor::Fatal, "unable to build shader");
@@ -476,15 +476,38 @@ struct MetalBackendFactory : IShaderBackendFactory
                                                     slot.lighting, slot.post, slot.texCount, slot.texs));
             cachedSz += sources.back().first.size() + 1;
             cachedSz += sources.back().second.size() + 1;
+
+            boo::ZTest zTest;
+            switch (slot.depthTest)
+            {
+            case hecl::Backend::ZTest::Original:
+            default:
+                zTest = tag.getDepthTest() ? boo::ZTest::LEqual : boo::ZTest::None;
+                break;
+            case hecl::Backend::ZTest::None:
+                zTest = boo::ZTest::None;
+                break;
+            case hecl::Backend::ZTest::LEqual:
+                zTest = boo::ZTest::LEqual;
+                break;
+            case hecl::Backend::ZTest::Greater:
+                zTest = boo::ZTest::Greater;
+                break;
+            case hecl::Backend::ZTest::Equal:
+                zTest = boo::ZTest::Equal;
+                break;
+            }
+
             boo::IShaderPipeline* ret =
             static_cast<boo::MetalDataFactory::Context&>(ctx).
                 newShaderPipeline(sources.back().first.c_str(), sources.back().second.c_str(),
                                   tag.newVertexFormat(ctx), m_rtHint,
                                   boo::BlendFactor((slot.srcFactor == hecl::Backend::BlendFactor::Original) ? m_backend.m_blendSrc : slot.srcFactor),
                                   boo::BlendFactor((slot.dstFactor == hecl::Backend::BlendFactor::Original) ? m_backend.m_blendDst : slot.dstFactor),
-                                  tag.getPrimType(),
-                                  tag.getDepthTest(), tag.getDepthWrite(),
-                                  tag.getBackfaceCulling() ? boo::CullMode::Backface : boo::CullMode::None);
+                                  tag.getPrimType(), zTest, slot.noDepthWrite ? false : tag.getDepthWrite(),
+                                  !slot.noColorWrite, !slot.noAlphaWrite,
+                                  slot.frontfaceCull ? boo::CullMode::Frontface :
+                                  (tag.getBackfaceCulling() ? boo::CullMode::Backface : boo::CullMode::None));
             if (!ret)
                 Log.report(logvisor::Fatal, "unable to build shader");
             returnFunc(ret);
@@ -528,15 +551,37 @@ struct MetalBackendFactory : IShaderBackendFactory
             if (r.hasError())
                 return false;
 
+            boo::ZTest zTest;
+            switch (slot.depthTest)
+            {
+            case hecl::Backend::ZTest::Original:
+            default:
+                zTest = tag.getDepthTest() ? boo::ZTest::LEqual : boo::ZTest::None;
+                break;
+            case hecl::Backend::ZTest::None:
+                zTest = boo::ZTest::None;
+                break;
+            case hecl::Backend::ZTest::LEqual:
+                zTest = boo::ZTest::LEqual;
+                break;
+            case hecl::Backend::ZTest::Greater:
+                zTest = boo::ZTest::Greater;
+                break;
+            case hecl::Backend::ZTest::Equal:
+                zTest = boo::ZTest::Equal;
+                break;
+            }
+
             boo::IShaderPipeline* ret =
             static_cast<boo::MetalDataFactory::Context&>(ctx).
                 newShaderPipeline(vertSource.c_str(), fragSource.c_str(),
                                   tag.newVertexFormat(ctx), m_rtHint,
                                   boo::BlendFactor((slot.srcFactor == hecl::Backend::BlendFactor::Original) ? blendSrc : slot.srcFactor),
                                   boo::BlendFactor((slot.dstFactor == hecl::Backend::BlendFactor::Original) ? blendDst : slot.dstFactor),
-                                  tag.getPrimType(),
-                                  tag.getDepthTest(), tag.getDepthWrite(),
-                                  tag.getBackfaceCulling() ? boo::CullMode::Backface : boo::CullMode::None);
+                                  tag.getPrimType(), zTest, slot.noDepthWrite ? false : tag.getDepthWrite(),
+                                  !slot.noColorWrite, !slot.noAlphaWrite,
+                                  slot.frontfaceCull ? boo::CullMode::Frontface :
+                                  (tag.getBackfaceCulling() ? boo::CullMode::Backface : boo::CullMode::None));
             if (!ret)
                 Log.report(logvisor::Fatal, "unable to build shader");
             returnFunc(ret);