From: Mikko Rasa <tdb@tdb.fi>
Date: Wed, 19 Jun 2019 23:01:43 +0000 (+0300)
Subject: Some refactoring of the draw code path
X-Git-Url: http://git.tdb.fi/?a=commitdiff_plain;h=f50822b9e73a6ecdacbc4af4c4d9aba435a72386;p=libs%2Fgl.git

Some refactoring of the draw code path

These changes make it easier to add instanced versions of the draw calls.
---

diff --git a/source/batch.cpp b/source/batch.cpp
index 37e4801e..a59fad99 100644
--- a/source/batch.cpp
+++ b/source/batch.cpp
@@ -225,6 +225,17 @@ unsigned Batch::get_index(unsigned i) const
 }
 
 void Batch::draw() const
+{
+	BindRestore _bind_ibuf(get_buffer(), ELEMENT_ARRAY_BUFFER);
+	const void *data_ptr = setup_draw();
+
+	if(EXT_draw_range_elements)
+		glDrawRangeElements(prim_type, min_index, max_index, size(), data_type, data_ptr);
+	else
+		glDrawElements(prim_type, size(), data_type, data_ptr);
+}
+
+const void *Batch::setup_draw() const
 {
 	if(restart)
 	{
@@ -242,23 +253,15 @@ void Batch::draw() const
 	else if(restart_index && restart_index<=max_index)
 		set_restart_index(0);
 
-	const Buffer *ibuf = get_buffer();
-	const void *data_ptr;
-	BindRestore _bind_ibuf(ibuf, ELEMENT_ARRAY_BUFFER);
-	if(ibuf)
+	if(get_buffer())
 	{
 		if(dirty)
 			update_buffer();
 
-		data_ptr = reinterpret_cast<const void *>(get_offset());
+		return reinterpret_cast<const void *>(get_offset());
 	}
 	else
-		data_ptr = &data[0];
-
-	if(EXT_draw_range_elements)
-		glDrawRangeElements(prim_type, min_index, max_index, size(), data_type, data_ptr);
-	else
-		glDrawElements(prim_type, size(), data_type, data_ptr);
+		return &data[0];
 }
 
 void Batch::set_restart_index(unsigned index)
diff --git a/source/batch.h b/source/batch.h
index 10c61a28..7212383e 100644
--- a/source/batch.h
+++ b/source/batch.h
@@ -66,6 +66,7 @@ public:
 
 	void draw() const;
 private:
+	const void *setup_draw() const;
 	static void set_restart_index(unsigned);
 };
 
diff --git a/source/renderer.cpp b/source/renderer.cpp
index e59949a3..53a3f452 100644
--- a/source/renderer.cpp
+++ b/source/renderer.cpp
@@ -269,15 +269,6 @@ void Renderer::draw(const Batch &batch)
 {
 	apply_state();
 
-	bool legacy_bindings = (!state->shprog || state->shprog->uses_legacy_variables());
-	if(state->mesh && legacy_bindings)
-	{
-		if(const Buffer *ibuf = state->mesh->get_index_buffer())
-			ibuf->bind_to(ELEMENT_ARRAY_BUFFER);
-		else
-			Buffer::unbind_from(ELEMENT_ARRAY_BUFFER);
-	}
-
 	batch.draw();
 }
 
@@ -386,6 +377,10 @@ void Renderer::apply_state()
 		{
 			Mesh::unbind();
 			state->mesh->get_vertices().apply();
+			if(const Buffer *ibuf = state->mesh->get_index_buffer())
+				ibuf->bind_to(ELEMENT_ARRAY_BUFFER);
+			else
+				Buffer::unbind_from(ELEMENT_ARRAY_BUFFER);
 		}
 		else
 			state->mesh->bind();