From 4973085a1594f4575ea380a6e98f62bfef160be5 Mon Sep 17 00:00:00 2001
From: Christophe Geuzaine <cgeuzaine@ulg.ac.be>
Date: Fri, 2 Sep 2005 15:53:55 +0000
Subject: [PATCH] Fixed horrible performance of vertex array creation on
Windows for very large post-pro views (> 1 millon triangles). The bottleneck
is the memory reallocation, which is 100 (?) times slower than on Linux/Mac.
Introduced some simple heuristics to estimate how many primitives will be
displayed. A prepro pass (like for smooth normals) would be a more elegant
solution.
---
Graphics/Post.cpp | 28 +++++++++++++++++++++++++---
1 file changed, 25 insertions(+), 3 deletions(-)
diff --git a/Graphics/Post.cpp b/Graphics/Post.cpp
index a40ae312bb..0ce651644d 100644
--- a/Graphics/Post.cpp
+++ b/Graphics/Post.cpp
@@ -1,4 +1,4 @@
-// $Id: Post.cpp,v 1.100 2005-05-21 17:27:03 geuzaine Exp $
+// $Id: Post.cpp,v 1.101 2005-09-02 15:53:55 geuzaine Exp $
//
// Copyright (C) 1997-2005 C. Geuzaine, J.-F. Remacle
//
@@ -430,6 +430,28 @@ void Draw_List(Post_View * v, double ValMin, double ValMax, int type,
}
}
+// We try to estimate how many primitives will end up in the vertex
+// arrays, since reallocating the arrays takes a HUGE amount of time
+// on Windows/Cygwin. A better way would be to slightly redisign the
+// drawing routines so we can have different pre-processing steps
+// (like the one we have for normals right now), in order to count how
+// many primitives we will have.
+
+int EstimateNumTri(Post_View *v)
+{
+ int num2d = v->NbST + v->NbSQ;
+ int num3d = v->NbSS + v->NbSH + v->NbSI + v->NbSY;
+
+ int heuristic = num2d + num3d/10;
+
+ return (heuristic < 10000) ? 10000 : heuristic;
+}
+
+int EstimateNumLin(Post_View *v)
+{
+ return 10000;
+}
+
void Draw_Post(void)
{
int nb;
@@ -646,10 +668,10 @@ void Draw_Post(void)
if(v->Changed){
Msg(DEBUG, "regenerate View[%d] vertex array", v->Index);
if(v->TriVertexArray) delete v->TriVertexArray;
- v->TriVertexArray = new VertexArray(3, 10000);
+ v->TriVertexArray = new VertexArray(3, EstimateNumTri(v));
v->TriVertexArray->fill = 1;
if(v->LinVertexArray) delete v->LinVertexArray;
- v->LinVertexArray = new VertexArray(2, 10000);
+ v->LinVertexArray = new VertexArray(2, EstimateNumLin(v));
v->LinVertexArray->fill = 1;
goto pass_0;
}
--
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