Removed non-textured and flat shaded support because it really clutters up

the API and I don't believe we'd have any hope of running at any kind of
reasonable frame rates on a non-hardware-3d accelerated box these days anyway.

diff --git a/simgear/scene/material/mat.cxx b/simgear/scene/material/mat.cxx
index a0c4557d44650e0b1d8cd95e23e22a80e631ed56..77f74969e26dc0fdf096658e51897e97e3f8eeb3 100644 (file)
--- a/simgear/scene/material/mat.cxx
+++ b/simgear/scene/material/mat.cxx
@@ -253,31 +253,24 @@ SGMaterial::ObjectGroup::get_object (int index) const
 ////////////////////////////////////////////////////////////////////////
 
 
-SGMaterial::SGMaterial( const string &fg_root,
-                    const SGPropertyNode *props,
-                    bool smooth_shading,
-                    bool use_textures )
+SGMaterial::SGMaterial( const string &fg_root, const SGPropertyNode *props )
 {
     init();
     read_properties( fg_root, props );
-    build_ssg_state( false, smooth_shading, use_textures );
+    build_ssg_state( false );
 }
 
-SGMaterial::SGMaterial( const string &texpath,
-                    bool smooth_shading,
-                    bool use_textures )
+SGMaterial::SGMaterial( const string &texpath )
 {
     init();
     texture_path = texpath;
-    build_ssg_state( true, smooth_shading, use_textures );
+    build_ssg_state( true );
 }
 
-SGMaterial::SGMaterial( ssgSimpleState *s,
-                    bool smooth_shading,
-                    bool use_textures )
+SGMaterial::SGMaterial( ssgSimpleState *s )
 {
     init();
-    set_ssg_state( s, smooth_shading, use_textures );
+    set_ssg_state( s );
 }
 
 SGMaterial::~SGMaterial (void)
@@ -354,9 +347,7 @@ void
 SGMaterial::init ()
 {
     texture_path = "";
-    state = 0;
-    textured = 0;
-    nontextured = 0;
+    state = NULL;
     xsize = 0;
     ysize = 0;
     wrapu = true;
@@ -374,13 +365,12 @@ SGMaterial::init ()
 bool
 SGMaterial::load_texture ()
 {
-    if (texture_loaded) {
+    if ( texture_loaded ) {
         return false;
     } else {
         SG_LOG( SG_GENERAL, SG_INFO, "Loading deferred texture "
                 << texture_path );
-        textured->setTexture( (char *)texture_path.c_str(),
-                              wrapu, wrapv, mipmap );
+        state->setTexture( (char *)texture_path.c_str(), wrapu, wrapv, mipmap );
         texture_loaded = true;
         return true;
     }
@@ -388,140 +378,55 @@ SGMaterial::load_texture ()
 
 
 void 
-SGMaterial::build_ssg_state( bool defer_tex_load,
-                           bool smooth_shading,
-                           bool use_textures )
+SGMaterial::build_ssg_state( bool defer_tex_load )
 {
-    GLenum shade_model = ( smooth_shading ? GL_SMOOTH : GL_FLAT);
+    GLenum shade_model = GL_SMOOTH;
     
-    state = new ssgStateSelector(2);
+    state = new ssgSimpleState();
     state->ref();
 
-    textured = new ssgSimpleState();
-    textured->ref();
-
-    nontextured = new ssgSimpleState();
-    nontextured->ref();
-
     // Set up the textured state
-    textured->setShadeModel( shade_model );
-    textured->enable( GL_LIGHTING );
-    textured->enable ( GL_CULL_FACE ) ;
-    textured->enable( GL_TEXTURE_2D );
-    textured->disable( GL_BLEND );
-    textured->disable( GL_ALPHA_TEST );
+    state->setShadeModel( shade_model );
+    state->enable( GL_LIGHTING );
+    state->enable ( GL_CULL_FACE ) ;
+    state->enable( GL_TEXTURE_2D );
+    state->disable( GL_BLEND );
+    state->disable( GL_ALPHA_TEST );
     if ( !defer_tex_load ) {
         SG_LOG(SG_INPUT, SG_INFO, "    " << texture_path );
-       textured->setTexture( (char *)texture_path.c_str(), wrapu, wrapv );
+       state->setTexture( (char *)texture_path.c_str(), wrapu, wrapv );
        texture_loaded = true;
     } else {
        texture_loaded = false;
     }
-    textured->enable( GL_COLOR_MATERIAL );
+    state->enable( GL_COLOR_MATERIAL );
 #if 0
-    textured->setColourMaterial( GL_AMBIENT_AND_DIFFUSE );
-    textured->setMaterial( GL_EMISSION, 0, 0, 0, 1 );
-    textured->setMaterial( GL_SPECULAR, 0, 0, 0, 1 );
+    state->setColourMaterial( GL_AMBIENT_AND_DIFFUSE );
+    state->setMaterial( GL_EMISSION, 0, 0, 0, 1 );
+    state->setMaterial( GL_SPECULAR, 0, 0, 0, 1 );
 #else
-    textured->setMaterial ( GL_AMBIENT,
+    state->setMaterial ( GL_AMBIENT,
                             ambient[0], ambient[1],
                             ambient[2], ambient[3] ) ;
-    textured->setMaterial ( GL_DIFFUSE,
+    state->setMaterial ( GL_DIFFUSE,
                             diffuse[0], diffuse[1],
                             diffuse[2], diffuse[3] ) ;
-    textured->setMaterial ( GL_SPECULAR,
+    state->setMaterial ( GL_SPECULAR,
                             specular[0], specular[1],
                             specular[2], specular[3] ) ;
-    textured->setMaterial ( GL_EMISSION,
+    state->setMaterial ( GL_EMISSION,
                             emission[0], emission[1],
                             emission[2], emission[3] ) ;
-    textured->setShininess ( shininess );
+    state->setShininess ( shininess );
 #endif
-
-    // Set up the coloured state
-    nontextured->enable( GL_LIGHTING );
-    nontextured->setShadeModel( shade_model );
-    nontextured->enable ( GL_CULL_FACE      ) ;
-    nontextured->disable( GL_TEXTURE_2D );
-    nontextured->disable( GL_BLEND );
-    nontextured->disable( GL_ALPHA_TEST );
-    nontextured->disable( GL_COLOR_MATERIAL );
-
-    nontextured->setMaterial ( GL_AMBIENT, 
-                              ambient[0], ambient[1], 
-                              ambient[2], ambient[3] ) ;
-    nontextured->setMaterial ( GL_DIFFUSE, 
-                              diffuse[0], diffuse[1], 
-                              diffuse[2], diffuse[3] ) ;
-    nontextured->setMaterial ( GL_SPECULAR, 
-                              specular[0], specular[1], 
-                              specular[2], specular[3] ) ;
-    nontextured->setMaterial ( GL_EMISSION, 
-                              emission[0], emission[1], 
-                              emission[2], emission[3] ) ;
-    nontextured->setShininess ( shininess );
-
-    state->setStep( 0, textured );    // textured
-    state->setStep( 1, nontextured ); // untextured
-
-    // Choose the appropriate starting state.
-    if ( use_textures ) {
-       state->selectStep(0);
-    } else {
-       state->selectStep(1);
-    }
 }
 
 
-void SGMaterial::set_ssg_state( ssgSimpleState *s,
-                              bool smooth_shading, bool use_textures )
+void SGMaterial::set_ssg_state( ssgSimpleState *s )
 {
-    GLenum shade_model = ( smooth_shading ? GL_SMOOTH : GL_FLAT);
-
-    state = new ssgStateSelector(2);
+    state = s;
     state->ref();
-
-    textured = s;
     texture_loaded = true;
-
-    nontextured = new ssgSimpleState();
-    nontextured->ref();
-
-    // Set up the textured state
-    textured->setShadeModel( shade_model );
-
-    // Set up the coloured state
-    nontextured->enable( GL_LIGHTING );
-    nontextured->setShadeModel( shade_model );
-    nontextured->enable ( GL_CULL_FACE      ) ;
-    nontextured->disable( GL_TEXTURE_2D );
-    nontextured->disable( GL_BLEND );
-    nontextured->disable( GL_ALPHA_TEST );
-    nontextured->disable( GL_COLOR_MATERIAL );
-
-    nontextured->setMaterial ( GL_AMBIENT, 
-                              ambient[0], ambient[1], 
-                              ambient[2], ambient[3] ) ;
-    nontextured->setMaterial ( GL_DIFFUSE, 
-                              diffuse[0], diffuse[1], 
-                              diffuse[2], diffuse[3] ) ;
-    nontextured->setMaterial ( GL_SPECULAR, 
-                              specular[0], specular[1], 
-                              specular[2], specular[3] ) ;
-    nontextured->setMaterial ( GL_EMISSION, 
-                              emission[0], emission[1], 
-                              emission[2], emission[3] ) ;
-    nontextured->setShininess ( shininess );
-
-    state->setStep( 0, textured );    // textured
-    state->setStep( 1, nontextured ); // untextured
-
-    // Choose the appropriate starting state.
-    if ( use_textures ) {
-       state->selectStep(0);
-    } else {
-       state->selectStep(1);
-    }
 }
 
 // end of newmat.cxx

diff --git a/simgear/scene/material/mat.hxx b/simgear/scene/material/mat.hxx
index 4bdd42fa153873db2891f6ca937708d90381d282..66bf19e9735ee8dc176709be9a735f04e08fa6eb 100644 (file)
--- a/simgear/scene/material/mat.hxx
+++ b/simgear/scene/material/mat.hxx
@@ -231,8 +231,7 @@ public:
    * state information for the material.  This node is usually
    * loaded from the $FG_ROOT/materials.xml file.
    */
-  SGMaterial( const string &fg_root, const SGPropertyNode *props,
-            bool smooth_shading, bool use_textures );
+  SGMaterial( const string &fg_root, const SGPropertyNode *props );
 
 
   /**
@@ -241,7 +240,7 @@ public:
    * @param texture_path A string containing an absolute path
    * to a texture file (usually RGB).
    */
-  SGMaterial( const string &texpath, bool smooth_shading, bool use_textures );
+  SGMaterial( const string &texpath );
 
 
   /**
@@ -253,7 +252,7 @@ public:
    *
    * @param s The SSG state for this material.
    */
-  SGMaterial( ssgSimpleState *s, bool smooth_shading, bool use_textures );
+  SGMaterial( ssgSimpleState *s );
 
   /**
    * Destructor.
@@ -278,7 +277,7 @@ public:
   /**
    * Get the textured state.
    */
-  virtual inline ssgSimpleState *get_textured () { return textured; }
+  virtual inline ssgSimpleState *get_state () const { return state; }
 
 
   /**
@@ -317,12 +316,6 @@ public:
   }
 
 
-  /**
-   * Get the current state.
-   */
-  virtual inline ssgStateSelector *get_state () const { return state; }
-
-
   /**
    * Increment the reference count for this material.
    *
@@ -369,9 +362,7 @@ private:
   string texture_path;
 
   // pointers to ssg states
-  ssgStateSelector *state;
-  ssgSimpleState *textured;
-  ssgSimpleState *nontextured;
+  ssgSimpleState *state;
 
   // texture size
   double xsize, ysize;
@@ -407,11 +398,8 @@ private:
   SGMaterial( const string &fg_root, const SGMaterial &mat ); // unimplemented
 
   void read_properties( const string &fg_root, const SGPropertyNode *props );
-  void build_ssg_state( bool defer_tex_load,
-                        bool smooth_shading,
-                        bool use_textures );
-  void set_ssg_state( ssgSimpleState *s,
-                      bool smooth_shading, bool use_textures );
+  void build_ssg_state( bool defer_tex_load );
+  void set_ssg_state( ssgSimpleState *s );
 
 
 };

diff --git a/simgear/scene/material/matlib.cxx b/simgear/scene/material/matlib.cxx
index 3a8d102b7f1d82b6bdc8e3aa463da263af58bc8b..a865ab7ea42b200c000cd256168fec94148a89b0 100644 (file)
--- a/simgear/scene/material/matlib.cxx
+++ b/simgear/scene/material/matlib.cxx
@@ -61,7 +61,6 @@ SGMaterialLib material_lib;
 
 // Constructor
 SGMaterialLib::SGMaterialLib ( void ) {
-  set_step(0);
 }
 
 
@@ -244,7 +243,7 @@ bool SGMaterialLib::load( const string &fg_root, const string& mpath ) {
     for (int i = 0; i < nMaterials; i++) {
         const SGPropertyNode * node = materials.getChild(i);
         if (!strcmp(node->getName(), "material")) {
-            SGMaterial *m = new SGMaterial( fg_root, node, true, true );
+            SGMaterial *m = new SGMaterial( fg_root, node );
 
             vector<SGPropertyNode_ptr>names = node->getChildren("name");
             for ( unsigned int j = 0; j < names.size(); j++ ) {
@@ -273,7 +272,7 @@ bool SGMaterialLib::load( const string &fg_root, const string& mpath ) {
     gnd_lights->enable( GL_BLEND );
     gnd_lights->disable( GL_ALPHA_TEST );
     gnd_lights->disable( GL_LIGHTING );
-    matlib["GROUND_LIGHTS"] = new SGMaterial( gnd_lights, true, true );
+    matlib["GROUND_LIGHTS"] = new SGMaterial( gnd_lights );
 
     GLuint tex_name;
 
@@ -292,10 +291,10 @@ bool SGMaterialLib::load( const string &fg_root, const string& mpath ) {
     rwy_white_lights->setMaterial ( GL_SPECULAR, 0.0, 0.0, 0.0, 0.0 );
     rwy_white_lights->setMaterial ( GL_EMISSION, 0.0, 0.0, 0.0, 0.0 );
     rwy_white_lights->setTexture( tex_name );
-    matlib["RWY_WHITE_LIGHTS"] = new SGMaterial( rwy_white_lights, true, true );
+    matlib["RWY_WHITE_LIGHTS"] = new SGMaterial( rwy_white_lights );
     // For backwards compatibility ... remove someday
-    matlib["RUNWAY_LIGHTS"] = new SGMaterial( rwy_white_lights, true, true );
-    matlib["RWY_LIGHTS"] = new SGMaterial( rwy_white_lights, true, true );
+    matlib["RUNWAY_LIGHTS"] = new SGMaterial( rwy_white_lights );
+    matlib["RWY_LIGHTS"] = new SGMaterial( rwy_white_lights );
     // end of backwards compatitibilty
 
     // hard coded runway medium intensity white light state
@@ -314,7 +313,7 @@ bool SGMaterialLib::load( const string &fg_root, const string& mpath ) {
     rwy_white_medium_lights->setMaterial ( GL_EMISSION, 0.0, 0.0, 0.0, 0.0 );
     rwy_white_medium_lights->setTexture( tex_name );
     matlib["RWY_WHITE_MEDIUM_LIGHTS"]
-        = new SGMaterial( rwy_white_medium_lights, true, true );
+        = new SGMaterial( rwy_white_medium_lights );
 
     // hard coded runway low intensity white light state
     tex_name = gen_standard_dir_light_map( 235, 235, 195, 155 );
@@ -332,7 +331,7 @@ bool SGMaterialLib::load( const string &fg_root, const string& mpath ) {
     rwy_white_low_lights->setMaterial ( GL_EMISSION, 0.0, 0.0, 0.0, 0.0 );
     rwy_white_low_lights->setTexture( tex_name );
     matlib["RWY_WHITE_LOW_LIGHTS"]
-        = new SGMaterial( rwy_white_low_lights, true, true );
+        = new SGMaterial( rwy_white_low_lights );
 
     // hard coded runway yellow light state
     tex_name = gen_standard_dir_light_map( 235, 215, 20, 255 );
@@ -349,7 +348,7 @@ bool SGMaterialLib::load( const string &fg_root, const string& mpath ) {
     rwy_yellow_lights->setMaterial ( GL_SPECULAR, 0.0, 0.0, 0.0, 0.0 );
     rwy_yellow_lights->setMaterial ( GL_EMISSION, 0.0, 0.0, 0.0, 0.0 );
     rwy_yellow_lights->setTexture( tex_name );
-    matlib["RWY_YELLOW_LIGHTS"] = new SGMaterial( rwy_yellow_lights, true, true );
+    matlib["RWY_YELLOW_LIGHTS"] = new SGMaterial( rwy_yellow_lights );
 
     // hard coded runway medium intensity yellow light state
     tex_name = gen_standard_dir_light_map( 235, 215, 20, 205 );
@@ -367,7 +366,7 @@ bool SGMaterialLib::load( const string &fg_root, const string& mpath ) {
     rwy_yellow_medium_lights->setMaterial ( GL_EMISSION, 0.0, 0.0, 0.0, 0.0 );
     rwy_yellow_medium_lights->setTexture( tex_name );
     matlib["RWY_YELLOW_MEDIUM_LIGHTS"]
-        = new SGMaterial( rwy_yellow_medium_lights, true, true );
+        = new SGMaterial( rwy_yellow_medium_lights );
 
     // hard coded runway low intensity yellow light state
     tex_name = gen_standard_dir_light_map( 235, 215, 20, 155 );
@@ -385,7 +384,7 @@ bool SGMaterialLib::load( const string &fg_root, const string& mpath ) {
     rwy_yellow_low_lights->setMaterial ( GL_EMISSION, 0.0, 0.0, 0.0, 0.0 );
     rwy_yellow_low_lights->setTexture( tex_name );
     matlib["RWY_YELLOW_LOW_LIGHTS"]
-        = new SGMaterial( rwy_yellow_low_lights, true, true );
+        = new SGMaterial( rwy_yellow_low_lights );
 
     // hard coded runway red light state
     tex_name = gen_standard_dir_light_map( 235, 90, 90, 255 );
@@ -403,7 +402,7 @@ bool SGMaterialLib::load( const string &fg_root, const string& mpath ) {
     rwy_red_lights->setMaterial ( GL_EMISSION, 0.0, 0.0, 0.0, 0.0 );
     rwy_red_lights->setTexture( tex_name );
     matlib["RWY_RED_LIGHTS"]
-        = new SGMaterial( rwy_red_lights, true, true );
+        = new SGMaterial( rwy_red_lights );
 
     // hard coded medium intensity runway red light state
     tex_name = gen_standard_dir_light_map( 235, 90, 90, 205 );
@@ -421,7 +420,7 @@ bool SGMaterialLib::load( const string &fg_root, const string& mpath ) {
     rwy_red_medium_lights->setMaterial ( GL_EMISSION, 0.0, 0.0, 0.0, 0.0 );
     rwy_red_medium_lights->setTexture( tex_name );
     matlib["RWY_RED_MEDIUM_LIGHTS"]
-        = new SGMaterial( rwy_red_medium_lights, true, true );
+        = new SGMaterial( rwy_red_medium_lights );
 
     // hard coded low intensity runway red light state
     tex_name = gen_standard_dir_light_map( 235, 90, 90, 205 );
@@ -439,7 +438,7 @@ bool SGMaterialLib::load( const string &fg_root, const string& mpath ) {
     rwy_red_low_lights->setMaterial ( GL_EMISSION, 0.0, 0.0, 0.0, 0.0 );
     rwy_red_low_lights->setTexture( tex_name );
     matlib["RWY_RED_LOW_LIGHTS"]
-        = new SGMaterial( rwy_red_low_lights, true, true );
+        = new SGMaterial( rwy_red_low_lights );
 
     // hard coded runway green light state
     tex_name = gen_standard_dir_light_map( 20, 235, 20, 255 );
@@ -457,7 +456,7 @@ bool SGMaterialLib::load( const string &fg_root, const string& mpath ) {
     rwy_green_lights->setMaterial ( GL_EMISSION, 0.0, 0.0, 0.0, 0.0 );
     rwy_green_lights->setTexture( tex_name );
     matlib["RWY_GREEN_LIGHTS"]
-        = new SGMaterial( rwy_green_lights, true, true );
+        = new SGMaterial( rwy_green_lights );
 
     // hard coded medium intensity runway green light state
     tex_name = gen_standard_dir_light_map( 20, 235, 20, 205 );
@@ -475,7 +474,7 @@ bool SGMaterialLib::load( const string &fg_root, const string& mpath ) {
     rwy_green_medium_lights->setMaterial ( GL_EMISSION, 0.0, 0.0, 0.0, 0.0 );
     rwy_green_medium_lights->setTexture( tex_name );
     matlib["RWY_GREEN_MEDIUM_LIGHTS"]
-        = new SGMaterial( rwy_green_medium_lights, true, true );
+        = new SGMaterial( rwy_green_medium_lights );
 
     // hard coded low intensity runway green light state
     tex_name = gen_standard_dir_light_map( 20, 235, 20, 205 );
@@ -493,7 +492,7 @@ bool SGMaterialLib::load( const string &fg_root, const string& mpath ) {
     rwy_green_low_lights->setMaterial ( GL_EMISSION, 0.0, 0.0, 0.0, 0.0 );
     rwy_green_low_lights->setTexture( tex_name );
     matlib["RWY_GREEN_LOW_LIGHTS"]
-        = new SGMaterial( rwy_green_low_lights, true, true );
+        = new SGMaterial( rwy_green_low_lights );
 
     // hard coded low intensity taxiway blue light state
     tex_name = gen_taxiway_dir_light_map( 90, 90, 235, 205 );
@@ -511,7 +510,7 @@ bool SGMaterialLib::load( const string &fg_root, const string& mpath ) {
     taxiway_blue_low_lights->setMaterial ( GL_EMISSION, 0.0, 0.0, 0.0, 0.0 );
     taxiway_blue_low_lights->setTexture( tex_name );
     matlib["RWY_BLUE_TAXIWAY_LIGHTS"]
-        = new SGMaterial( taxiway_blue_low_lights, true, true );
+        = new SGMaterial( taxiway_blue_low_lights );
 
     // hard coded runway vasi light state
     ssgSimpleState *rwy_vasi_lights = new ssgSimpleState();
@@ -527,7 +526,7 @@ bool SGMaterialLib::load( const string &fg_root, const string& mpath ) {
     rwy_vasi_lights->setMaterial ( GL_SPECULAR, 0.0, 0.0, 0.0, 0.0 );
     rwy_vasi_lights->setMaterial ( GL_EMISSION, 0.0, 0.0, 0.0, 0.0 );
     rwy_vasi_lights->setTexture( gen_vasi_light_map() );
-    matlib["RWY_VASI_LIGHTS"] = new SGMaterial( rwy_vasi_lights, true, true );
+    matlib["RWY_VASI_LIGHTS"] = new SGMaterial( rwy_vasi_lights );
 
     return true;
 }
@@ -554,7 +553,7 @@ bool SGMaterialLib::add_item ( const string &mat_name, const string &full_path )
     SG_LOG( SG_TERRAIN, SG_INFO, "  Loading material " 
            << mat_name << " (" << full_path << ")");
 
-    material_lib.matlib[mat_name] = new SGMaterial( full_path, true, true );
+    material_lib.matlib[mat_name] = new SGMaterial( full_path );
 
     return true;
 }
@@ -563,7 +562,7 @@ bool SGMaterialLib::add_item ( const string &mat_name, const string &full_path )
 // Load a library of material properties
 bool SGMaterialLib::add_item ( const string &mat_name, ssgSimpleState *state )
 {
-    SGMaterial *m = new SGMaterial( state, true, true );
+    SGMaterial *m = new SGMaterial( state );
 
     SG_LOG( SG_TERRAIN, SG_INFO, "  Loading material given a premade "
            << "ssgSimpleState = " << mat_name );
@@ -600,28 +599,6 @@ SGMaterialLib::~SGMaterialLib ( void ) {
 }
 
 
-// Set the step for all of the state selectors in the material slots
-void SGMaterialLib::set_step ( int step )
-{
-    // container::iterator it = begin();
-    for ( material_map_iterator it = begin(); it != end(); it++ ) {
-       const string &key = it->first;
-       SG_LOG( SG_GENERAL, SG_INFO,
-               "Updating material " << key << " to step " << step );
-       SGMaterial *slot = it->second;
-       slot->get_state()->selectStep(step);
-    }
-}
-
-
-// Get the step for the state selectors
-int SGMaterialLib::get_step ()
-{
-  material_map_iterator it = begin();
-  return it->second->get_state()->getSelectStep();
-}
-
-
 // Load one pending "deferred" texture.  Return true if a texture
 // loaded successfully, false if no pending, or error.
 void SGMaterialLib::load_next_deferred() {

diff --git a/simgear/scene/material/matlib.hxx b/simgear/scene/material/matlib.hxx
index ccebc6863c1d1b73cf976ec9d03d2c7b89ed3c70..1a6e459a644006cd9d503a3077012d8a8d9290d6 100644 (file)
--- a/simgear/scene/material/matlib.hxx
+++ b/simgear/scene/material/matlib.hxx
@@ -74,9 +74,6 @@ public:
     // find a material record by material name
     SGMaterial *find( const string& material );
 
-    void set_step (int step);
-    int get_step ();
-
     /**
      * Load the next deferred texture, if there is any.
      */