From f5c5a344f05364b912c6aefef15383bb00edd326 Mon Sep 17 00:00:00 2001
From: dtatarnikov <strong2much@gmail.com>
Date: Thu, 6 Jul 2023 13:55:56 +0700
Subject: [PATCH] Fix #481

---
 src/Veldrid/OpenGL/OpenGLCommandExecutor.cs | 51 ++++++++++++++++-----
 1 file changed, 39 insertions(+), 12 deletions(-)

diff --git a/src/Veldrid/OpenGL/OpenGLCommandExecutor.cs b/src/Veldrid/OpenGL/OpenGLCommandExecutor.cs
index 789b2833e..e86051231 100644
--- a/src/Veldrid/OpenGL/OpenGLCommandExecutor.cs
+++ b/src/Veldrid/OpenGL/OpenGLCommandExecutor.cs
@@ -94,28 +94,55 @@ public void ClearColorTarget(uint index, RgbaFloat clearColor)
 
         public void ClearDepthStencil(float depth, byte stencil)
         {
-            glClearDepth_Compat(depth);
-            CheckLastError();
+            if (_graphicsPipeline != null)
+            {
+                if (!_graphicsPipeline.DepthStencilState.DepthWriteEnabled)
+                {
+                    glDepthMask(true);
+                    CheckLastError();
+                }
+
+                if (_graphicsPipeline.DepthStencilState.StencilWriteMask != 0xFF)
+                {
+                    glStencilMask(0xFF);
+                    CheckLastError();
+                }
 
-            glStencilMask(~0u);
+                if (_graphicsPipeline.RasterizerState.ScissorTestEnabled)
+                {
+                    glDisable(EnableCap.ScissorTest);
+                    CheckLastError();
+                }
+            }
+
+            glClearDepth_Compat(depth);
             CheckLastError();
 
             glClearStencil(stencil);
             CheckLastError();
 
-            if (_graphicsPipeline != null && _graphicsPipeline.RasterizerState.ScissorTestEnabled)
-            {
-                glDisable(EnableCap.ScissorTest);
-                CheckLastError();
-            }
-
-            glDepthMask(true);
             glClear(ClearBufferMask.DepthBufferBit | ClearBufferMask.StencilBufferBit);
             CheckLastError();
 
-            if (_graphicsPipeline != null && _graphicsPipeline.RasterizerState.ScissorTestEnabled)
+            if (_graphicsPipeline != null)
             {
-                glEnable(EnableCap.ScissorTest);
+                if (!_graphicsPipeline.DepthStencilState.DepthWriteEnabled)
+                {
+                    glDepthMask(false);
+                    CheckLastError();
+                }
+
+                if (_graphicsPipeline.DepthStencilState.StencilWriteMask != 0xFF)
+                {
+                    glStencilMask(_graphicsPipeline.DepthStencilState.StencilWriteMask);
+                    CheckLastError();
+                }
+
+                if (_graphicsPipeline.RasterizerState.ScissorTestEnabled)
+                {
+                    glEnable(EnableCap.ScissorTest);
+                    CheckLastError();
+                }
             }
         }