Fixed: System textures are released and freed when changing game modes.

Refactored management of abstract textures and their namespaces to allow
partially clearing the texture database. It is now possible to clear by
texture type (system or runtime) or by texture namespace (TN_*).

Now when a game change occurs only textures marked "runtime" are cleared.

doomsday/engine/portable/include/gl_texmanager.h

@@ -74,7 +74,6 @@ void GL_InitTextureManager(void);
 void GL_ResetTextureManager(void);
 
 void GL_ShutdownTextureManager(void);
-void GL_DestroyTextures(void);
 
 void GL_TexReset(void);
 
@@ -104,6 +103,12 @@ void GL_ReleaseSystemTextures(void);
  */
 void GL_ReleaseTexturesForRawImages(void);
 
+void GL_DestroyTextures(void);
+
+void GL_DestroyRuntimeTextures(void);
+
+void GL_DestroySystemTextures(void);
+
 /**
  * Called when changing the value of any cvar affecting texture quality which
  * in turn calls GL_TexReset. Added to remove the need for reseting manually.

doomsday/engine/portable/include/texture.h

@@ -26,6 +26,7 @@
 #define LIBDENG_GL_TEXTURE_H
 
 struct texturevariant_s;
+struct texturenamespace_hashnode_s;
 
 typedef enum {
     TEXTURE_ANALYSIS_FIRST = 0,
@@ -57,6 +58,7 @@ typedef struct texture_s {
     /// Unique Texture Namespace Identifier.
     /// \todo make external.
     texturenamespaceid_t _texNamespace;
+    struct texturenamespace_hashnode_s* _texNamespaceHashNode;
 
     /// List of variants (e.g., color translations).
     struct texture_variantlist_node_s* _variants;
@@ -69,10 +71,8 @@ typedef struct texture_s {
     char _name[9];
 } texture_t;
 
-texture_t* Texture_Construct(textureid_t id, const char name[9],
-    texturenamespaceid_t texNamespace, int index);
-texture_t* Texture_Construct2(textureid_t id, const char name[9],
-    texturenamespaceid_t texNamespace, int index, int width, int height);
+texture_t* Texture_Construct(textureid_t id, const char name[9], int index);
+texture_t* Texture_Construct2(textureid_t id, const char name[9], int index, int width, int height);
 
 void Texture_Destruct(texture_t* tex);
 
@@ -160,4 +160,9 @@ int Texture_TypeIndex(const texture_t* tex);
 /// @return  Texture namespace identifier.
 texturenamespaceid_t Texture_Namespace(const texture_t* tex);
 
+/// @return  Texture namespace hash node.
+struct texturenamespace_hashnode_s* Texture_NamespaceHashNode(const texture_t* tex);
+
+void Texture_SetNamespace(texture_t* tex, texturenamespaceid_t texNamespace,
+    struct texturenamespace_hashnode_s* texNamespaceHashNode);
 #endif /* LIBDENG_GL_TEXTURE_H */

doomsday/engine/portable/src/dd_main.c

@@ -1045,14 +1045,13 @@ boolean DD_ChangeGame2(gameinfo_t* info, boolean allowReload)
     if(netGame)
         Con_Execute(CMDS_DDAY, isServer ? "net server close" : "net disconnect", true, false);
 
-    GL_PurgeDeferredTasks();
-    GL_SetFilter(false);
     S_Reset();
     Demo_StopPlayback();
 
-    GL_ReleaseRuntimeTextures();
-    //GL_ShutdownFont();
+    GL_PurgeDeferredTasks();
+    GL_ClearTextureMemory();
     UI_ReleaseTextures();
+    GL_SetFilter(false);
 
     // If a game is presently loaded; unload it.
     if(!DD_IsNullGameInfo(DD_GameInfo()))
@@ -1096,8 +1095,7 @@ boolean DD_ChangeGame2(gameinfo_t* info, boolean allowReload)
         R_ClearPatchTexs();
         R_DestroyColorPalettes();
 
-        /// \fixme dj: We do not want to destroy *everything*!
-        GL_DestroyTextures();
+        GL_DestroyRuntimeTextures();
 
         Sfx_InitLogical();
         P_InitThinkerLists(0x1|0x2);
@@ -2230,7 +2228,8 @@ materialnamespaceid_t DD_ParseFontNamespace(const char* str)
 
 const ddstring_t* DD_TextureNamespaceNameForId(texturenamespaceid_t id)
 {
-    static const ddstring_t namespaceNames[TEXTURENAMESPACE_COUNT] = {
+    static const ddstring_t namespaceNames[TEXTURENAMESPACE_COUNT+1] = {
+        /* No namespace name */         { "" },
         /* TN_SYSTEM */                 { TN_SYSTEM_NAME },
         /* TN_FLATS */                  { TN_FLATS_NAME  },
         /* TN_TEXTURES */               { TN_TEXTURES_NAME },
@@ -2245,8 +2244,8 @@ const ddstring_t* DD_TextureNamespaceNameForId(texturenamespaceid_t id)
         /* TN_FLAREMAPS */              { TN_FLAREMAPS_NAME }
     };
     if(VALID_TEXTURENAMESPACE(id))
-        return &namespaceNames[id - TEXTURENAMESPACE_FIRST];
-    return NULL;
+        return namespaceNames + 1 + (id - TEXTURENAMESPACE_FIRST);
+    return namespaceNames + 0;
 }
 
 materialnum_t DD_MaterialForTextureIndex(uint index, texturenamespaceid_t texNamespace)