From a5a26e4e2eb2d0b05c3531b667411be657ac74f1 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Thu, 13 May 2021 14:16:33 +0300
Subject: [PATCH] Clear VertexSetup state when a Mesh is unloaded

---
 source/core/mesh.cpp        |  1 +
 source/core/vertexsetup.cpp | 30 ++++++++++++++++++++++++++++++
 source/core/vertexsetup.h   |  2 ++
 3 files changed, 33 insertions(+)

diff --git a/source/core/mesh.cpp b/source/core/mesh.cpp
index f8135dc8..f63b3293 100644
--- a/source/core/mesh.cpp
+++ b/source/core/mesh.cpp
@@ -216,6 +216,7 @@ void Mesh::unload()
 	vertices.clear();
 	vertices.use_buffer(0);
 	batches.clear();
+	vtx_setup.unload();
 	delete vbuf;
 	delete ibuf;
 	vbuf = 0;
diff --git a/source/core/vertexsetup.cpp b/source/core/vertexsetup.cpp
index 4b2e2a5f..d9e9d095 100644
--- a/source/core/vertexsetup.cpp
+++ b/source/core/vertexsetup.cpp
@@ -210,6 +210,36 @@ void VertexSetup::unbind()
 		glBindVertexArray(0);
 }
 
+void VertexSetup::unload()
+{
+	if(ARB_direct_state_access)
+	{
+		glVertexArrayVertexBuffer(id, 0, 0, 0, 0);
+		glVertexArrayVertexBuffer(id, 1, 0, 0, 0);
+		glVertexArrayElementBuffer(id, 0);
+	}
+	else
+	{
+		BindRestore _bind(*this);
+		Buffer::unbind_from(ARRAY_BUFFER);
+
+		unsigned mask = get_attribs(vertex_format)|get_attribs(inst_format);
+		for(unsigned i=0; mask; ++i, mask>>=1)
+			if(mask&1)
+			{
+				glDisableVertexAttribArray(i);
+				glVertexAttribPointer(i, 1, GL_FLOAT, false, 0, 0);
+			}
+		glBindBuffer(ELEMENT_ARRAY_BUFFER, 0);
+	}
+
+	vertex_array = 0;
+	vertex_format = VertexFormat();
+	inst_array = 0;
+	inst_format = VertexFormat();
+	index_buffer = 0;
+}
+
 void VertexSetup::set_debug_name(const string &name)
 {
 #ifdef DEBUG
diff --git a/source/core/vertexsetup.h b/source/core/vertexsetup.h
index 06422a08..51183af5 100644
--- a/source/core/vertexsetup.h
+++ b/source/core/vertexsetup.h
@@ -56,6 +56,8 @@ public:
 	void bind() const;
 	static void unbind();
 
+	void unload();
+
 	void set_debug_name(const std::string &);
 };
 
-- 
2.43.0