From aaa761e33312c771ce2c353d82feb1c6bc827bb8 Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Thu, 10 Apr 2003 19:32:32 +0000
Subject: [PATCH] Added tests for presense of extensions to osgcubemap,
 osgvertexproram and osgmultitexture examples.

Added osg::VertexProgram::Extensions class to better handle multiple graphics
context vertex program extensions.
---
 examples/osgcubemap/osgcubemap.cpp            |  17 +++
 examples/osgmultitexture/osgmultitexture.cpp  |  15 ++
 .../osgvertexprogram/osgvertexprogram.cpp     |  16 +++
 include/osg/StateAttribute                    |   4 +-
 include/osg/Texture                           |   4 +
 include/osg/VertexProgram                     |  51 +++++++
 src/osg/Texture.cpp                           |   8 ++
 src/osg/VertexProgram.cpp                     | 134 +++++++++++++++---
 8 files changed, 225 insertions(+), 24 deletions(-)

diff --git a/examples/osgcubemap/osgcubemap.cpp b/examples/osgcubemap/osgcubemap.cpp
index a666217cc..62c457a66 100644
--- a/examples/osgcubemap/osgcubemap.cpp
+++ b/examples/osgcubemap/osgcubemap.cpp
@@ -129,6 +129,23 @@ int main(int argc, char *argv[])
     // create the windows and run the threads.
     viewer.realize();
 
+
+    // now check to see if texture cube map is supported.
+    for(unsigned int contextID = 0; 
+        contextID<viewer.getDisplaySettings()->getMaxNumberOfGraphicsContexts();
+        ++contextID)
+    {
+        osg::TextureCubeMap::Extensions* tcmExt = osg::TextureCubeMap::getExtensions(contextID,false);
+        if (tcmExt)
+        {
+            if (!tcmExt->isCubeMapSupported())
+            {
+                cout<<"Warning: texture_cube_map not supported by OpenGL drivers, unable to run application."<<std::endl;
+                return 1;
+            }
+        }
+    }
+
     while( !viewer.done() )
     {
         // wait for all cull and draw threads to complete.
diff --git a/examples/osgmultitexture/osgmultitexture.cpp b/examples/osgmultitexture/osgmultitexture.cpp
index e5bdbebca..236b84e24 100644
--- a/examples/osgmultitexture/osgmultitexture.cpp
+++ b/examples/osgmultitexture/osgmultitexture.cpp
@@ -101,6 +101,21 @@ int main( int argc, char **argv )
     // create the windows and run the threads.
     viewer.realize();
 
+    for(unsigned int contextID = 0; 
+        contextID<viewer.getDisplaySettings()->getMaxNumberOfGraphicsContexts();
+        ++contextID)
+    {
+        osg::Texture::Extensions* textExt = osg::Texture::getExtensions(contextID,false);
+        if (textExt)
+        {
+            if (!textExt->isMultiTexturingSupported())
+            {
+                cout<<"Warning: texture_cube_map not supported by OpenGL drivers, unable to run application."<<std::endl;
+                return 1;
+            }
+        }
+    }
+
     while( !viewer.done() )
     {
         // wait for all cull and draw threads to complete.
diff --git a/examples/osgvertexprogram/osgvertexprogram.cpp b/examples/osgvertexprogram/osgvertexprogram.cpp
index 590531da2..d244273f1 100644
--- a/examples/osgvertexprogram/osgvertexprogram.cpp
+++ b/examples/osgvertexprogram/osgvertexprogram.cpp
@@ -405,6 +405,22 @@ int main(int argc, char *argv[])
     // create the windows and run the threads.
     viewer.realize();
 
+    // now check to see if vertex program is supported.
+    for(unsigned int contextID = 0; 
+        contextID<viewer.getDisplaySettings()->getMaxNumberOfGraphicsContexts();
+        ++contextID)
+    {
+        osg::VertexProgram::Extensions* vpExt = osg::VertexProgram::getExtensions(contextID,false);
+        if (vpExt)
+        {
+            if (!vpExt->isVertexProgramSupported())
+            {
+                cout<<"Warning: ARB_vertex_program not supported by OpenGL drivers, unable to run application."<<std::endl;
+                return 1;
+            }
+        }
+    }
+
     while( !viewer.done() )
     {
         // wait for all cull and draw threads to complete.
diff --git a/include/osg/StateAttribute b/include/osg/StateAttribute
index a6880eb15..039ce237e 100644
--- a/include/osg/StateAttribute
+++ b/include/osg/StateAttribute
@@ -215,10 +215,10 @@ class SG_EXPORT StateAttribute : public Object
           * in to allow the StateAttribute to obtain details on the
           * the current context and state.
           */
-        virtual void apply(State&) const = 0 ;
+        virtual void apply(State&) const = 0;
         
         /** default to nothing to compile - all state is applied immediately. */
-        virtual void compile(State&) const {};
+        virtual void compile(State&) const {}
 
     protected:
     
diff --git a/include/osg/Texture b/include/osg/Texture
index d0f66a4e4..e753ebd92 100644
--- a/include/osg/Texture
+++ b/include/osg/Texture
@@ -251,6 +251,9 @@ class SG_EXPORT Texture : public osg::StateAttribute
                 
                 void setupGLExtenions();
 
+                void setMultiTexturingSupported(bool flag) { _isMultiTexturingSupported=flag; }
+                bool isMultiTexturingSupported() const { return _isMultiTexturingSupported; }
+
                 void setTextureFilterAnisotropicSupported(bool flag) { _isTextureFilterAnisotropicSupported=flag; }
                 bool isTextureFilterAnisotropicSupported() const { return _isTextureFilterAnisotropicSupported; }
                 
@@ -290,6 +293,7 @@ class SG_EXPORT Texture : public osg::StateAttribute
 
                 ~Extensions() {}
                 
+                bool    _isMultiTexturingSupported;
                 bool    _isTextureFilterAnisotropicSupported;
                 bool    _isTextureCompressionARBSupported;
                 bool    _isTextureCompressionS3TCSupported;
diff --git a/include/osg/VertexProgram b/include/osg/VertexProgram
index 04915c8a8..ba135e8ec 100644
--- a/include/osg/VertexProgram
+++ b/include/osg/VertexProgram
@@ -170,6 +170,57 @@ class SG_EXPORT VertexProgram : public StateAttribute
 
         virtual void apply(State& state) const;
 
+        virtual void compile(State& state) const { apply(state); }
+
+        /** Extensions class which encapsulates the querring of extensions and
+          * associated function pointers, and provide convinience wrappers to 
+          * check for the extensions or use the associated functions.*/        
+        class SG_EXPORT Extensions : public osg::Referenced
+        {
+            public:
+                Extensions();
+
+                Extensions(const Extensions& rhs);
+                
+                void lowestCommonDenominator(const Extensions& rhs);
+                
+                void setupGLExtenions();
+
+                void setVertexProgramSupported(bool flag) { _isVertexProgramSupported=flag; }
+                bool isVertexProgramSupported() const { return _isVertexProgramSupported; }
+
+                void glBindProgram(GLenum target, GLuint id) const;
+                void glGenPrograms(GLsizei n, GLuint *programs) const;
+                void glProgramString(GLenum target, GLenum format, GLsizei len, const void *string) const; 
+                void glProgramLocalParameter4fv(GLenum target, GLuint index, const GLfloat *params) const;
+
+            protected:
+
+                ~Extensions() {}
+                
+                bool _isVertexProgramSupported;
+                
+                void* _glBindProgram;
+                void* _glGenPrograms;
+                void* _glProgramString;
+                void* _glProgramLocalParameter4fv;
+ 
+        };
+        
+        /** Function to call to get the extension of a specified context.
+          * If the Exentsion object for that context has not yet been created then 
+          * and the 'createIfNotInitalized' flag been set to false then returns NULL.
+          * If 'createIfNotInitalized' is true then the Extensions object is 
+          * automatically created.  However, in this case the extension object 
+          * only be created with the graphics context associated with ContextID..*/
+        static Extensions* getExtensions(unsigned int contextID,bool createIfNotInitalized);
+
+        /** setExtensions allows users to override the extensions across graphics contexts.
+          * typically used when you have different extensions supported across graphics pipes
+          * but need to ensure that they all use the same low common denominator extensions.*/
+        static void setExtensions(unsigned int contextID,Extensions* extensions);
+
+
     protected:
 
 
diff --git a/src/osg/Texture.cpp b/src/osg/Texture.cpp
index ca2c5f23d..3a879cad4 100644
--- a/src/osg/Texture.cpp
+++ b/src/osg/Texture.cpp
@@ -850,6 +850,7 @@ Texture::Extensions::Extensions()
 Texture::Extensions::Extensions(const Extensions& rhs):
     Referenced()
 {
+    _isMultiTexturingSupported = rhs._isMultiTexturingSupported;
     _isTextureFilterAnisotropicSupported = rhs._isTextureFilterAnisotropicSupported;
     _isTextureCompressionARBSupported = rhs._isTextureCompressionARBSupported;
     _isTextureCompressionS3TCSupported = rhs._isTextureCompressionS3TCSupported;
@@ -865,6 +866,8 @@ Texture::Extensions::Extensions(const Extensions& rhs):
 
 void Texture::Extensions::lowestCommonDenominator(const Extensions& rhs)
 {
+    if (!rhs._isMultiTexturingSupported) _isMultiTexturingSupported = false;
+    
     if (!rhs._isTextureFilterAnisotropicSupported) _isTextureFilterAnisotropicSupported = false;
     if (!rhs._isTextureMirroredRepeatSupported) _isTextureMirroredRepeatSupported = false;
     if (!rhs._isTextureEdgeClampSupported) _isTextureEdgeClampSupported = false;
@@ -878,11 +881,16 @@ void Texture::Extensions::lowestCommonDenominator(const Extensions& rhs)
     if (rhs._maxTextureSize<_maxTextureSize) _maxTextureSize = rhs._maxTextureSize;
 
     if (!rhs._glCompressedTexImage2D) _glCompressedTexImage2D = 0;
+    if (!rhs._glCompressedTexSubImage2D) _glCompressedTexSubImage2D = 0;
+    if (!rhs._glGetCompressedTexImage) _glGetCompressedTexImage = 0;
 }
 
 void Texture::Extensions::setupGLExtenions()
 {
  
+    _isMultiTexturingSupported = (strncmp((const char*)glGetString(GL_VERSION),"1.3",3)>=0) ||
+                                 isGLExtensionSupported("GL_ARB_multitexture") ||
+                                 isGLExtensionSupported("GL_EXT_multitexture");
     _isTextureFilterAnisotropicSupported = isGLExtensionSupported("GL_EXT_texture_filter_anisotropic");
     _isTextureCompressionARBSupported = isGLExtensionSupported("GL_ARB_texture_compression");
     _isTextureCompressionS3TCSupported = isGLExtensionSupported("GL_EXT_texture_compression_s3tc");
diff --git a/src/osg/VertexProgram.cpp b/src/osg/VertexProgram.cpp
index 799d3431d..7b5685b02 100644
--- a/src/osg/VertexProgram.cpp
+++ b/src/osg/VertexProgram.cpp
@@ -32,25 +32,13 @@ VertexProgram::VertexProgram(const VertexProgram& vp,const CopyOp& copyop):
 VertexProgram::~VertexProgram()
 {}
 
-
-typedef void (APIENTRY * BindProgramProc) (GLenum target, GLuint id);
-typedef void (APIENTRY * GenProgramsProc) (GLsizei n, GLuint *programs);
-typedef void (APIENTRY * ProgramStringProc) (GLenum target, GLenum format, GLsizei len, const void *string); 
-typedef void (APIENTRY * ProgramLocalParameter4fvProc) (GLenum target, GLuint index, const GLfloat *params);
-
 void VertexProgram::apply(State& state) const
 {
-    static bool supported = osg::isGLExtensionSupported("GL_ARB_vertex_program");
-    if (!supported) return;
+    const unsigned int contextID = state.getContextID();
+    const Extensions* extensions = getExtensions(contextID,true);
 
-    static BindProgramProc s_glBindProgram =
-        (BindProgramProc)osg::getGLExtensionFuncPtr("glBindProgramARB");
-    static GenProgramsProc s_glGenPrograms =
-        (GenProgramsProc)osg::getGLExtensionFuncPtr("glGenProgramsARB");
-    static ProgramStringProc s_glProgramString =
-        (ProgramStringProc)osg::getGLExtensionFuncPtr("glProgramStringARB");
-    static ProgramLocalParameter4fvProc s_glProgramLocalParameter4fv =
-        (ProgramLocalParameter4fvProc)osg::getGLExtensionFuncPtr("glProgramLocalParameter4fvARB");
+    if (!extensions->isVertexProgramSupported())
+        return;
 
 
     GLuint& vertexProgramId=getVertexProgramID(state.getContextID());
@@ -58,15 +46,15 @@ void VertexProgram::apply(State& state) const
     // Vertex Program
     if (vertexProgramId != 0)
     {
-        s_glBindProgram( GL_VERTEX_PROGRAM_ARB, vertexProgramId );
+        extensions->glBindProgram( GL_VERTEX_PROGRAM_ARB, vertexProgramId );
     }
     else if (!_vertexProgram.empty())
     {
         ::glGetError(); // Reset Error flags.
-        s_glGenPrograms( 1, &vertexProgramId );
-        s_glBindProgram( GL_VERTEX_PROGRAM_ARB, vertexProgramId );
-        s_glProgramString( GL_VERTEX_PROGRAM_ARB, GL_PROGRAM_FORMAT_ASCII_ARB,
-            _vertexProgram.length(), _vertexProgram.c_str());
+        extensions->glGenPrograms( 1, &vertexProgramId );
+        extensions->glBindProgram( GL_VERTEX_PROGRAM_ARB, vertexProgramId );
+        extensions->glProgramString( GL_VERTEX_PROGRAM_ARB, GL_PROGRAM_FORMAT_ASCII_ARB,
+                                     _vertexProgram.length(), _vertexProgram.c_str());
 
         // Check for errors
         GLint errorposition;
@@ -93,7 +81,7 @@ void VertexProgram::apply(State& state) const
             itr!=_programLocalParameters.end();
             ++itr)
         {
-            s_glProgramLocalParameter4fv(GL_VERTEX_PROGRAM_ARB, (*itr).first, (*itr).second.ptr());
+            extensions->glProgramLocalParameter4fv(GL_VERTEX_PROGRAM_ARB, (*itr).first, (*itr).second.ptr());
         }
     }
 
@@ -112,3 +100,105 @@ void VertexProgram::apply(State& state) const
 }
 
 
+typedef buffered_value< ref_ptr<VertexProgram::Extensions> > BufferedExtensions;
+static BufferedExtensions s_extensions;
+
+VertexProgram::Extensions* VertexProgram::getExtensions(unsigned int contextID,bool createIfNotInitalized)
+{
+    if (!s_extensions[contextID] && createIfNotInitalized) s_extensions[contextID] = new Extensions;
+    return s_extensions[contextID].get();
+}
+
+void VertexProgram::setExtensions(unsigned int contextID,Extensions* extensions)
+{
+    s_extensions[contextID] = extensions;
+}
+
+VertexProgram::Extensions::Extensions()
+{
+    setupGLExtenions();
+}
+
+VertexProgram::Extensions::Extensions(const Extensions& rhs):
+    Referenced()
+{
+    _isVertexProgramSupported = rhs._isVertexProgramSupported;
+    _glBindProgram = rhs._glBindProgram;
+    _glGenPrograms = rhs._glGenPrograms;
+    _glProgramString = rhs._glProgramString;
+    _glProgramLocalParameter4fv = rhs._glProgramLocalParameter4fv;
+}
+
+
+void VertexProgram::Extensions::lowestCommonDenominator(const Extensions& rhs)
+{
+    if (!rhs._isVertexProgramSupported) _isVertexProgramSupported = false;
+
+    if (!rhs._glBindProgram) _glBindProgram = 0;
+    if (!rhs._glGenPrograms) _glGenPrograms = 0;
+    if (!rhs._glProgramString) _glProgramString = 0;
+    if (!rhs._glProgramLocalParameter4fv) _glProgramLocalParameter4fv = 0;
+
+}
+
+void VertexProgram::Extensions::setupGLExtenions()
+{
+    _isVertexProgramSupported = isGLExtensionSupported("GL_ARB_vertex_program");
+
+    _glBindProgram = osg::getGLExtensionFuncPtr("glBindProgramARB");
+    _glGenPrograms = osg::getGLExtensionFuncPtr("glGenProgramsARB");
+    _glProgramString = osg::getGLExtensionFuncPtr("glProgramStringARB");
+    _glProgramLocalParameter4fv = osg::getGLExtensionFuncPtr("glProgramLocalParameter4fvARB");
+}
+
+void VertexProgram::Extensions::glBindProgram(GLenum target, GLuint id) const
+{
+    if (_glBindProgram)
+    {
+        typedef void (APIENTRY * BindProgramProc) (GLenum target, GLuint id);
+        ((BindProgramProc)_glBindProgram)(target,id);
+    }
+    else
+    {
+        notify(WARN)<<"Error: glBindProgram not supported by OpenGL driver"<<std::endl;
+    }    
+}
+
+void VertexProgram::Extensions::glGenPrograms(GLsizei n, GLuint *programs) const
+{
+    if (_glGenPrograms)
+    {
+        typedef void (APIENTRY * GenProgramsProc) (GLsizei n, GLuint *programs);
+        ((GenProgramsProc)_glGenPrograms)(n,programs);
+    }
+    else
+    {
+        notify(WARN)<<"Error: glGenPrograms not supported by OpenGL driver"<<std::endl;
+    }
+}
+
+void VertexProgram::Extensions::glProgramString(GLenum target, GLenum format, GLsizei len, const void *string) const
+{
+    if (_glProgramString)
+    {
+        typedef void (APIENTRY * ProgramStringProc) (GLenum target, GLenum format, GLsizei len, const void *string); 
+        ((ProgramStringProc)_glProgramString)(target,format, len, string); 
+    }
+    else
+    {
+        notify(WARN)<<"Error: glProgramString not supported by OpenGL driver"<<std::endl;
+    }
+}
+
+void VertexProgram::Extensions::glProgramLocalParameter4fv(GLenum target, GLuint index, const GLfloat *params) const
+{
+    if (_glProgramLocalParameter4fv)
+    {
+        typedef void (APIENTRY * ProgramLocalParameter4fvProc) (GLenum target, GLuint index, const GLfloat *params);
+        ((ProgramLocalParameter4fvProc)_glProgramLocalParameter4fv)(target, index, params);
+    }
+    else
+    {
+        notify(WARN)<<"Error: glProgramLocalParameter4fv not supported by OpenGL driver"<<std::endl;
+    }
+}