From: Mikko Rasa <tdb@tdb.fi>
Date: Sun, 26 Aug 2012 10:09:44 +0000 (+0300)
Subject: Get all blocks for the program before applying them
X-Git-Url: http://git.tdb.fi/?a=commitdiff_plain;h=ab83db6f1e31d44ced585119a57fd10896e469cb;p=libs%2Fgl.git

Get all blocks for the program before applying them

This way, the correct size for the buffer can be determined right away,
rather than each block resizing it in turn.  Binding the buffer before
applying the blocks also avoids some thrashing.
---

diff --git a/source/programdata.cpp b/source/programdata.cpp
index 3e3f18db..e1b4212e 100644
--- a/source/programdata.cpp
+++ b/source/programdata.cpp
@@ -221,10 +221,21 @@ void ProgramData::apply() const
 		throw invalid_operation("ProgramData::apply");
 
 	const Program::UniformBlockMap &prog_blocks = prog->get_uniform_blocks();
-	for(Program::UniformBlockMap::const_iterator i=prog_blocks.begin(); i!=prog_blocks.end(); ++i)
+	if(!prog_blocks.empty())
 	{
-		const UniformBlock &block = get_block(*prog, &i->second);
-		block.apply(i->second.bind_point);
+		typedef pair<const UniformBlock *, unsigned> ApplyBlock;
+		list<ApplyBlock> apply_blocks;
+		for(Program::UniformBlockMap::const_iterator i=prog_blocks.begin(); i!=prog_blocks.end(); ++i)
+		{
+			const UniformBlock &block = get_block(*prog, &i->second);
+			apply_blocks.push_back(make_pair(&block, i->second.bind_point));
+		}
+
+		if(buffer)
+			buffer->bind();
+
+		for(list<ApplyBlock>::const_iterator i=apply_blocks.begin(); i!=apply_blocks.end(); ++i)
+			i->first->apply(i->second);
 	}
 
 	const UniformBlock &block = get_block(*prog, 0);