From 73567be7cd9e01e620cb2a8fa0ca381723b9a71f Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Sun, 5 Sep 2021 14:34:04 +0300
Subject: [PATCH] Store index type in VertexSetup

---
 source/core/mesh.cpp            | 4 +++-
 source/core/vertexsetup.cpp     | 6 ++++--
 source/core/vertexsetup.h       | 5 ++++-
 source/render/instancearray.cpp | 8 +++++---
 4 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/source/core/mesh.cpp b/source/core/mesh.cpp
index 38642d4e..77da81eb 100644
--- a/source/core/mesh.cpp
+++ b/source/core/mesh.cpp
@@ -89,7 +89,6 @@ void Mesh::check_buffers(unsigned mask)
 			ibuf = new Buffer;
 			if(!batches.empty())
 				batches.front().change_buffer(ibuf);
-			vtx_setup.set_index_buffer(*ibuf);
 			dirty |= INDEX_BUFFER;
 
 #ifdef DEBUG
@@ -97,6 +96,9 @@ void Mesh::check_buffers(unsigned mask)
 				vbuf->set_debug_name(debug_name+" [IBO]");
 #endif
 		}
+
+		if(!batches.empty())
+			vtx_setup.set_index_buffer(*ibuf, batches.front().get_index_type());
 	}
 }
 
diff --git a/source/core/vertexsetup.cpp b/source/core/vertexsetup.cpp
index f077ad2e..86c9f0f2 100644
--- a/source/core/vertexsetup.cpp
+++ b/source/core/vertexsetup.cpp
@@ -23,7 +23,8 @@ VertexSetup::VertexSetup():
 	dirty(0),
 	vertex_array(0),
 	inst_array(0),
-	index_buffer(0)
+	index_buffer(0),
+	index_type(UNSIGNED_SHORT)
 {
 	static Require req(ARB_vertex_array_object);
 	if(ARB_direct_state_access)
@@ -86,9 +87,10 @@ void VertexSetup::set_instance_array(const VertexArray &a)
 	dirty |= INSTANCE_ARRAY;
 }
 
-void VertexSetup::set_index_buffer(const Buffer &ibuf)
+void VertexSetup::set_index_buffer(const Buffer &ibuf, DataType itype)
 {
 	index_buffer = &ibuf;
+	index_type = itype;
 	dirty |= INDEX_BUFFER;
 }
 
diff --git a/source/core/vertexsetup.h b/source/core/vertexsetup.h
index 7eb903ae..756f5bc0 100644
--- a/source/core/vertexsetup.h
+++ b/source/core/vertexsetup.h
@@ -1,6 +1,7 @@
 #ifndef MSP_GL_VERTEXSETUP_H_
 #define MSP_GL_VERTEXSETUP_H_
 
+#include "datatype.h"
 #include "vertexformat.h"
 
 namespace Msp {
@@ -30,6 +31,7 @@ private:
 	const VertexArray *inst_array;
 	VertexFormat inst_format;
 	const Buffer *index_buffer;
+	DataType index_type;
 
 public:
 	VertexSetup();
@@ -40,10 +42,11 @@ public:
 
 	void set_vertex_array(const VertexArray &);
 	void set_instance_array(const VertexArray &);
-	void set_index_buffer(const Buffer &);
+	void set_index_buffer(const Buffer &, DataType);
 	const VertexArray *get_vertex_array() const { return vertex_array; }
 	const VertexArray *get_instance_array() const { return inst_array; }
 	const Buffer *get_index_buffer() const { return index_buffer; }
+	DataType get_index_type() const { return index_type; }
 
 private:
 	static bool verify_format(const VertexFormat &);
diff --git a/source/render/instancearray.cpp b/source/render/instancearray.cpp
index 11279f76..039a50ec 100644
--- a/source/render/instancearray.cpp
+++ b/source/render/instancearray.cpp
@@ -51,10 +51,12 @@ InstanceArray::InstanceArray(const Object &o):
 		instance_buffer = new Buffer;
 		instance_data->use_buffer(instance_buffer);
 
+		const Mesh *mesh = object.get_mesh();
+
 		vtx_setup = new VertexSetup;
-		vtx_setup->set_format_instanced(object.get_mesh()->get_vertices().get_format(), fmt);
-		vtx_setup->set_vertex_array(object.get_mesh()->get_vertices());
-		vtx_setup->set_index_buffer(*object.get_mesh()->get_index_buffer());
+		vtx_setup->set_format_instanced(mesh->get_vertices().get_format(), fmt);
+		vtx_setup->set_vertex_array(mesh->get_vertices());
+		vtx_setup->set_index_buffer(*mesh->get_index_buffer(), mesh->get_batches().front().get_index_type());
 		vtx_setup->set_instance_array(*instance_data);
 	}
 	else
-- 
2.43.0