From 2cd6a174d22fab03f7d484b239b807c91e1ff853 Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Wed, 9 May 2007 10:41:56 +0000
Subject: [PATCH] Added GL_MAX_TEXTURE_SIZE check and use of
 OSG_MAX_TEXTURE_SIZE env var to help hint to osgText that the native OpenGL
 implementation only supports textures up to a given size.

---
 src/osgText/Font.cpp | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/osgText/Font.cpp b/src/osgText/Font.cpp
index 99c56f114..4837c6e43 100644
--- a/src/osgText/Font.cpp
+++ b/src/osgText/Font.cpp
@@ -135,8 +135,8 @@ Font::Font(FontImplementation* implementation):
     _height(16),
     _margin(1),
     _marginRatio(0.02),
-    _textureWidthHint(1024),
-    _textureHeightHint(1024),
+    _textureWidthHint(8000),
+    _textureHeightHint(8000),
     _minFilterHint(osg::Texture::LINEAR_MIPMAP_LINEAR),
     _magFilterHint(osg::Texture::LINEAR)
 {
@@ -514,6 +514,15 @@ void Font::GlyphTexture::apply(osg::State& state) const
 
     if (newTextureObject)
     {
+        GLint maxTextureSize = 256;
+        glGetIntegerv(GL_MAX_TEXTURE_SIZE, &maxTextureSize);
+        if (maxTextureSize < getTextureWidth() || maxTextureSize < getTextureHeight())
+        {
+            osg::notify(osg::WARN)<<"Warning: osgText::Font texture size of ("<<getTextureWidth()<<", "<<getTextureHeight()<<") too large, unable to create font texture."<<std::endl;
+            osg::notify(osg::WARN)<<"         Maximum supported by hardward by native OpenGL implementation is ("<<maxTextureSize<<","<<maxTextureSize<<")."<<std::endl;
+            osg::notify(osg::WARN)<<"         Please set OSG_MAX_TEXTURE_SIZE lenvironment variable to "<<maxTextureSize<<" and re-run application."<<std::endl;
+            return;
+        }
         
         // being bound for the first time, need to allocate the texture