From ac45dc9cba44e2d923a86229ff7771091cacbb0c Mon Sep 17 00:00:00 2001
From: Laurent Gomila <laurent.gom@gmail.com>
Date: Tue, 27 Mar 2012 17:09:19 +0200
Subject: [PATCH] GL states are no longer polluted by SFML's ones when mixing
 with custom OpenGL code

---
 include/SFML/Graphics/RenderTarget.hpp |  1 +
 src/SFML/Graphics/RenderTarget.cpp     | 12 ++++++++++--
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/include/SFML/Graphics/RenderTarget.hpp b/include/SFML/Graphics/RenderTarget.hpp
index 9f868dea..9e618051 100644
--- a/include/SFML/Graphics/RenderTarget.hpp
+++ b/include/SFML/Graphics/RenderTarget.hpp
@@ -354,6 +354,7 @@ private :
     {
         enum {VertexCacheSize = 4};
 
+        bool      glStatesSet;    ///< Are our internal GL states set yet?
         bool      viewChanged;    ///< Has the current view changed since last draw?
         BlendMode lastBlendMode;  ///< Cached blending mode
         Uint64    lastTextureId;  ///< Cached texture
diff --git a/src/SFML/Graphics/RenderTarget.cpp b/src/SFML/Graphics/RenderTarget.cpp
index a50c472d..c7d0104a 100644
--- a/src/SFML/Graphics/RenderTarget.cpp
+++ b/src/SFML/Graphics/RenderTarget.cpp
@@ -42,6 +42,7 @@ m_defaultView(),
 m_view       (),
 m_cache      ()
 {
+    m_cache.glStatesSet = false;
 }
 
 
@@ -136,6 +137,10 @@ void RenderTarget::draw(const Vertex* vertices, unsigned int vertexCount,
 
     if (activate(true))
     {
+        // First set the persistent OpenGL states if it's the very first call
+        if (!m_cache.glStatesSet)
+            resetGLStates();
+
         // Check if the vertex count is low enough so that we can pre-transform them
         bool useVertexCache = (vertexCount <= StatesCache::VertexCacheSize);
         if (useVertexCache)
@@ -217,6 +222,7 @@ void RenderTarget::pushGLStates()
 {
     if (activate(true))
     {
+        glCheck(glPushClientAttrib(GL_CLIENT_ALL_ATTRIB_BITS));
         glCheck(glPushAttrib(GL_ALL_ATTRIB_BITS));
         glCheck(glMatrixMode(GL_MODELVIEW));
         glCheck(glPushMatrix());
@@ -235,6 +241,7 @@ void RenderTarget::popGLStates()
 {
     if (activate(true))
     {
+        glCheck(glPopClientAttrib());
         glCheck(glPopAttrib());
         glCheck(glMatrixMode(GL_PROJECTION));
         glCheck(glPopMatrix());
@@ -264,6 +271,7 @@ void RenderTarget::resetGLStates()
         glCheck(glEnableClientState(GL_VERTEX_ARRAY));
         glCheck(glEnableClientState(GL_COLOR_ARRAY));
         glCheck(glEnableClientState(GL_TEXTURE_COORD_ARRAY));
+        m_cache.glStatesSet = true;
 
         // Apply the default SFML states
         applyBlendMode(BlendAlpha);
@@ -286,8 +294,8 @@ void RenderTarget::initialize()
     m_defaultView.reset(FloatRect(0, 0, static_cast<float>(getSize().x), static_cast<float>(getSize().y)));
     m_view = m_defaultView;
 
-    // Initialize the default OpenGL render-states
-    resetGLStates();
+    // Set GL states only on first draw, so that we don't pollute user's states
+    m_cache.glStatesSet = false;
 }