diff --git a/port/dAssimp/assimp/config.d b/port/dAssimp/assimp/config.d
index b9e26e732..f20106ca7 100644
--- a/port/dAssimp/assimp/config.d
+++ b/port/dAssimp/assimp/config.d
@@ -131,11 +131,11 @@ extern ( C ) {
    /**
     * Configures the <code>PretransformVertices</code> step to keep the scene
     * hierarchy. Meshes are moved to worldspace, but no optimization is
-    * performed (means: meshes are not joined. The total number of meshes won't
-    * change).
+    * performed (meshes with equal materials are not joined, the total number
+    * of meshes will not change).
     *
     * This option could be of use for you if the scene hierarchy contains
-    * important additional information which you want to interpret.
+    * important additional information which you intend to parse.
     * For rendering, you can still render all meshes in the scene without
     * any transformations.
     *
@@ -145,6 +145,17 @@ extern ( C ) {
     */
    const char* AI_CONFIG_PP_PTV_KEEP_HIERARCHY = "PP_PTV_KEEP_HIERARCHY";
 
+   /**
+    * Configures the <code>PretransformVertices</code> step to normalize all
+    * vertex components into the -1...1 range. That is, a bounding box for the
+    * whole scene is computed, the maximum component is taken and all meshes
+    * are scaled appropriately (uniformly of course!).
+    *
+    * This might be useful if you don't know the spatial dimension of the input
+    * data.
+    */
+   const char* AI_CONFIG_PP_PTV_NORMALIZE = "PP_PTV_NORMALIZE";
+
    /**
     * Configures the <code>FindDegenerates</code> step to remove degenerated
     * primitives from the import – immediately.
@@ -380,6 +391,21 @@ extern ( C ) {
     */
    const char* AI_CONFIG_PP_SBP_REMOVE = "PP_SBP_REMOVE";
 
+   /**
+    * Input parameter to the <code>FindInvalidData</code> step:
+    * Specifies the floating-point accuracy for animation values.
+    *
+    * The step checks for animation tracks where all frame values are
+    * absolutely equal and removes them. This tweakable controls the epsilon
+    * for floating-point comparisons – two keys are considered equal if the
+    * invariant abs(n0-n1) > epsilon holds true for all vector respectively
+    * quaternion components.
+    *
+    * Default value: 0 (exact comparison).
+    *
+    * Property type: float.
+    */
+   const char* AI_CONFIG_PP_FID_ANIM_ACCURACY = "PP_FID_ANIM_ACCURACY";
 
    /**
     * The <code>TransformUVCoords</code> step evaluates UV scalings.
@@ -623,4 +649,15 @@ extern ( C ) {
     * Property type: integer.
     */
    const char* AI_CONFIG_IMPORT_IRR_ANIM_FPS = "IMPORT_IRR_ANIM_FPS";
-}
\ No newline at end of file
+
+   /**
+    * Ogre Importer will try to load this material file.
+    *
+    * Ogre Mehs contain only the material name, not the material file. If there
+    * is no material file with the same name as the material, Ogre Importer
+    * will try to load this file and search the material in it.
+    *
+    * Property type: string. Default value: "Scene.material".
+    */
+   const char* AI_CONFIG_IMPORT_OGRE_MATERIAL_FILE = "IMPORT_OGRE_MATERIAL_FILE";
+}
diff --git a/port/dAssimp/assimp/fileIO.d b/port/dAssimp/assimp/fileIO.d
index d0ee2ed87..d893016d8 100644
--- a/port/dAssimp/assimp/fileIO.d
+++ b/port/dAssimp/assimp/fileIO.d
@@ -64,12 +64,12 @@ extern ( C ) {
    alias char* aiUserData;
 
    /**
-    * Defines Assimp's way of accessing files.
+    * File system callbacks.
     *
     * Provided are functions to open and close files. Supply a custom structure
     * to the import function. If you don't, a default implementation is used.
-    * Use this to enable reading from other sources, such as ZIPs or memory
-    * locations.
+    * Use custom file systems to enable reading from other sources, such as
+    * ZIPs or memory locations.
     */
    struct aiFileIO {
       /**
@@ -89,7 +89,7 @@ extern ( C ) {
    }
 
    /**
-    * Represents a read/write file.
+    * File callbacks.
     *
     * Actually, it's a data structure to wrap a set of <code>fXXXX</code>
     * (e.g <code>fopen()</code>) replacement functions.
diff --git a/port/dAssimp/assimp/postprocess.d b/port/dAssimp/assimp/postprocess.d
index 377d5b934..a720a8c63 100644
--- a/port/dAssimp/assimp/postprocess.d
+++ b/port/dAssimp/assimp/postprocess.d
@@ -199,10 +199,15 @@ extern ( C ) {
        * this step.
        *
        * This step is intended for applications that have no scenegraph.
+       *
        * The step <em>can</em> cause some problems: if e.g. a mesh of the asset
        * contains normals and another, using the same material index, does not,
        * they will be brought together, but the first meshes's part of the
-       * normal list will be zeroed.
+       * normal list is zeroed. However, these artifacts are rare.
+       *
+       * Note: The <code>AI_CONFIG_PP_PTV_NORMALIZE</code> configuration
+       *    property can be set to normalize the scene's spatial dimension
+       *    to the -1...1 range.
        */
       PreTransformVertices = 0x100,
 
@@ -358,13 +363,17 @@ extern ( C ) {
 
       /**
        * This step searches all meshes for invalid data, such as zeroed normal
-       * vectors or invalid UV coords and removes them.
+       * vectors or invalid UV coords and removes/fixes them. This is intended
+       * to get rid of some common exporter errors.
        *
        * This is especially useful for normals. If they are invalid, and the
-       * step recognizes this, they will be removed and can later be computed
-       * by one of the other steps.
+       * step recognizes this, they will be removed and can later be
+       * recomputed, e.g. by the <code>GenSmoothNormals</code> step.
        *
-       * The step will also remove meshes that are infinitely small.
+       * The step will also remove meshes that are infinitely small and reduce
+       * animation tracks consisting of hundreds if redundant keys to a single
+       * key. The <code>AI_CONFIG_PP_FID_ANIM_ACCURACY</code> config property
+       * decides the accuracy of the check for duplicate animation tracks.
        */
       FindInvalidData = 0x20000,