From 7d6b7b18221e670810bdd0505995b8f1fa012eb4 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Thu, 30 Aug 2012 22:42:52 +0300
Subject: [PATCH] Make use of Bufferable in Batch

---
 source/batch.cpp | 88 +++++++-----------------------------------------
 source/batch.h   | 15 +++------
 source/mesh.cpp  |  2 +-
 3 files changed, 18 insertions(+), 87 deletions(-)

diff --git a/source/batch.cpp b/source/batch.cpp
index 1d9b1d4c..785fca82 100644
--- a/source/batch.cpp
+++ b/source/batch.cpp
@@ -56,12 +56,7 @@ Batch::Batch(PrimitiveType t):
 	data_type(UNSIGNED_BYTE),
 	min_index(0),
 	max_index(0),
-	restart(false),
-	ibuf(0),
-	ibuf_offset(0),
-	next_in_ibuf(0),
-	prev_in_ibuf(0),
-	dirty(false)
+	restart(false)
 {
 	/* XXX Should probably provide a fallback to glDrawElements since this class
 	is pretty much required to render anything. */
@@ -70,7 +65,6 @@ Batch::Batch(PrimitiveType t):
 
 Batch::~Batch()
 {
-	unlink_from_ibuf();
 }
 
 void Batch::set_data_type(DataType t)
@@ -96,57 +90,10 @@ void Batch::set_data_type(DataType t)
 		shrink<unsigned short, unsigned char>(data);
 
 	data_type = t;
-	update_ibuf_offsets();
+	update_offset();
 	dirty = true;
 }
 
-void Batch::use_index_buffer(Buffer *buf, Batch *prev)
-{
-	if(buf && prev && prev->ibuf!=buf)
-		throw invalid_argument("Batch::use_index_buffer");
-
-	if(!buf)
-	{
-		prev = 0;
-		unlink_from_ibuf();
-	}
-
-	ibuf = buf;
-	prev_in_ibuf = prev;
-	next_in_ibuf = 0;
-	if(prev)
-	{
-		prev->next_in_ibuf = this;
-		ibuf_offset = prev->ibuf_offset+prev->data.size();
-	}
-	else
-		ibuf_offset = 0;
-
-	dirty = true;
-}
-
-void Batch::unlink_from_ibuf()
-{
-	if(next_in_ibuf)
-		next_in_ibuf->prev_in_ibuf = prev_in_ibuf;
-	if(prev_in_ibuf)
-	{
-		prev_in_ibuf->next_in_ibuf = next_in_ibuf;
-		prev_in_ibuf->update_ibuf_offsets();
-	}
-	else if(next_in_ibuf)
-	{
-		next_in_ibuf->ibuf_offset = 0;
-		next_in_ibuf->update_ibuf_offsets();
-	}
-}
-
-void Batch::update_ibuf_offsets()
-{
-	for(Batch *b=this; b->next_in_ibuf; b=b->next_in_ibuf)
-		b->next_in_ibuf->ibuf_offset = b->ibuf_offset+b->data.size();
-}
-
 Batch &Batch::append(unsigned i)
 {
 	if(data.empty())
@@ -169,7 +116,7 @@ Batch &Batch::append(unsigned i)
 	else
 		data.push_back(i);
 	
-	update_ibuf_offsets();
+	update_offset();
 	dirty = true;
 
 	return *this;
@@ -213,6 +160,7 @@ void Batch::append(const vector<unsigned> &ind)
 		for(unsigned i=0; i<ind.size(); ++i)
 			data[base+i] = ind[i];
 	}
+	dirty = true;
 }
 
 void Batch::append(const Batch &other)
@@ -259,6 +207,11 @@ void Batch::append(const Batch &other)
 		append(other.get_index(i));
 }
 
+void Batch::upload_data() const
+{
+	get_buffer()->sub_data(get_offset(), data.size(), &data[0]);
+}
+
 unsigned Batch::get_index_size() const
 {
 	if(data_type==UNSIGNED_SHORT)
@@ -304,30 +257,15 @@ void Batch::draw() const
 		restart_index = 0;
 	}
 
-	if(ibuf)
+	if(get_buffer())
 	{
 		if(dirty)
-		{
-			const Batch *b = this;
-			for(; b->prev_in_ibuf; b=b->prev_in_ibuf) ;
-
-			unsigned chain_size = 0;
-			for(const Batch *a=b; a; a=a->next_in_ibuf)
-				chain_size += a->data.size();
-
-			ibuf->data(chain_size, 0);
-
-			for(; b; b=b->next_in_ibuf)
-			{
-				ibuf->sub_data(b->ibuf_offset, b->data.size(), &b->data[0]);
-				b->dirty = false;
-			}
-		}
+			update_buffer();
 
-		BufferAlias<ELEMENT_ARRAY_BUFFER> alias(*ibuf);
+		BufferAlias<ELEMENT_ARRAY_BUFFER> alias(*get_buffer());
 		Bind bind_ibuf(alias, true);
 
-		glDrawRangeElements(prim_type, min_index, max_index, size(), data_type, reinterpret_cast<void *>(ibuf_offset));
+		glDrawRangeElements(prim_type, min_index, max_index, size(), data_type, reinterpret_cast<void *>(get_offset()));
 	}
 	else
 		glDrawRangeElements(prim_type, min_index, max_index, size(), data_type, &data[0]);
diff --git a/source/batch.h b/source/batch.h
index dcc2168b..3c54089a 100644
--- a/source/batch.h
+++ b/source/batch.h
@@ -3,6 +3,7 @@
 
 #include <vector>
 #include <msp/datafile/objectloader.h>
+#include "bufferable.h"
 #include "datatype.h"
 #include "primitivetype.h"
 
@@ -19,7 +20,7 @@ the Batch.
 This is a pretty low-level class and mainly intended to be used by the Mesh
 class.
 */
-class Batch
+class Batch: public Bufferable
 {
 public:
 	class Loader: public DataFile::ObjectLoader<Batch>
@@ -37,11 +38,6 @@ private:
 	unsigned min_index;
 	unsigned max_index;
 	bool restart;
-	Buffer *ibuf;
-	unsigned ibuf_offset;
-	Batch *next_in_ibuf;
-	Batch *prev_in_ibuf;
-	mutable bool dirty;
 
 	static unsigned restart_index;
 
@@ -52,16 +48,13 @@ public:
 	PrimitiveType get_type() const { return prim_type; }
 	void set_data_type(DataType);
 	DataType get_data_type() const { return data_type; }
-	void use_index_buffer(Buffer *, Batch * = 0);
-private:
-	void unlink_from_ibuf();
-	void update_ibuf_offsets();
 
-public:
 	Batch &append(unsigned);
 	void append(const std::vector<unsigned> &);
 	void append(const Batch &);
 private:
+	virtual unsigned get_data_size() const { return data.size(); }
+	virtual void upload_data() const;
 	unsigned get_index_size() const;
 public:
 	unsigned size() const { return data.size()/get_index_size(); }
diff --git a/source/mesh.cpp b/source/mesh.cpp
index 9757df5c..0e58aa26 100644
--- a/source/mesh.cpp
+++ b/source/mesh.cpp
@@ -85,7 +85,7 @@ void Mesh::add_batch(const Batch &b)
 		Batch *prev = (batches.empty() ? 0 : &batches.back());
 		batches.push_back(b);
 		if(ibuf)
-			batches.back().use_index_buffer(ibuf, prev);
+			batches.back().use_buffer(ibuf, prev);
 	}
 }
 
-- 
2.43.0