The DirectX geometry export converter for Okino's PolyTrans program writes out complete 3d scene databases
in a highly robust and professionally guaranteed manner to
Microsoft's 'Direct 3D' file format, including all mesh data (vertex normals, vertex colors, uv texture coordinates), hierarchy,
texture references, automatic conversion of foreign bitmaps,
skin weights exported from select source programs (real time deformation of single skin
meshes by skeletons), as well as vertex duplication lists.
Object animation conversion, resampling and capture from 3ds Max, Maya, Softimage|XSI,
Lightwave, U3D, Collada, FBX, etc. to DirectX is a critical and key feature of the
DirectX exporter.
As Okino was the first company to proactively develop a DirectX converter in
cooperation with Microsoft around 1995, we personally guarantee professional conversions from all
main source programs, most importantly all animation and skinned mesh conversions such as from 3ds Max and Maya. DirectX is a notorious file format
and playback engine with unpublished quirks, and Okino has overcome all these quirks as part of the conversion process. This exporter has been bug free
and stable for well over a decade, being in use by every major DirectX professional 3D user, production studio and game studio
during that time. It is totally supported by Okino from its origins to today.
This DirectX export file converter is a complete implementation of the
DirectX file format specification. It also overcomes all the hard problems
associated with DirectX files such as splitting welded vertices into two
unique vertices so that proper texture mapping can be applied.
Some history:
There is much history to this exporter that many people are not aware of. For those who remember, back in the early to mid 1990's there was a war between companies to come out with the best and fastest 3D realtime rendering software toolkit, since OpenGL hadn't really become a standard yet and no (cheap) realtime video boards were available. The clear winner in our eyes, at that time, was "Reality Lab" from Rendermorphics in the U.K. It could do near realtime rendering of textured objects, something quite amazing for the time period. Microsoft wanted to become a leader in 3D multi-media and games, so it purchased the Rendermorphics company (U.K) and their 3 main developers to acquire its "Reality3D" toolkit. Microsoft also acquired a number of other technologies. These toolkits and technologies were then brought together under the framework and name of "DirectX".
Being a company which always jumps on new converter development, Okino and Robert Lansdale pursued the new DirectX development team monthly until we got the first DirectX file format specification under NDA. That spec grew and then shrank over time. Okino's first fully implemented DirectX exporter then began shipping in 1996. It was the first complete DirectX exporter available in the 3D industry. Half a year later, Okino introduced the first bidirectional animation conversion technology in a 3D software program, with 3ds Max, DirectX, Lightwave and Softimage being the 4 main programs originally supported.
When DirectX 8.1 came out, Okino invested 8 (ongoing) years dedicated completely to cross conversion of skinning data, just as we spent the mid to late 90's innovating on bidirectional animation conversion. While this may not sound interesting or difficult, cross conversion of skinned meshes and skeletons is the absolute hardest task in 3D conversion software, since all programs (particularly DirectX) have serious quirks in terms of handling skinned mesh data. Knowing from direct experience, and that from our customers, it would be safe to say that we have the best and cleanest bidirectional skinning conversion support between 3ds Max, Maya, XSI, Lightwave, FBX, Collada, U3D and DirectX, all bi-directional.
Over a decade has passed by and our DirectX exporter is still considered the industry standard. We have always personally guaranteed our conversion pipeline out to DirectX, since it works as well today as it did in 1996. Converters just don't break or stop working just because a new customer has purchased it! Microsoft's development team recommends it on their MSDN chats, and it would be safe to say that every major 3D DirectX user has used or owned this exporter in some manner in recents times. If you ever have questions or concerns about the exporter, just write to us since most questions relate to the limitations of the DirectX file format itself and not the exporter itself.
Notes About the DirectX File Format:
Due to the history of Rendermorphics + Microsoft, as explained above, the DirectX file format did not mature into the state it was orginally intended in the mid 90's. The main 3 Rendermorphics developers left Microsoft and that seems to have killed off future evolution of the DirectX file format (as told to us directly by the 3 ex-Rendermorphics developers in person at Siggraph). As such, there is no internal support for cameras, lights, embedded complex materials, or camera/light/material animation. If this situation changes then we will be pleased to expand our DirectX exporter to have these commonly expected items.
Proper translation of all forms of geometry into the DirectX 'Mesh' primitive,
complete with support for the 'MeshNormals', 'MeshMaterialList', 'MeshVertexColors', 'MeshTextureCoords' and 'FvFData'.
Guaranteed animation conversion from all major source animation systems -- that is our core business and competency in the DCC/animation market. DirectX needs at least 4 keys per animation curve to ensure proper playback.
Export of skin weights, from select source programs, for realtime deformation of single skin meshes by their associated bound skeletons (the skeletons are represented as frame hierarchies). All known DirectX skinning conversion quirks are automatically handled by the exporter. Okino has dedicated more than a dozen man years in its animation and skinning conversion systems, so we completely know how to make this happen for customers.
Export of vertex duplication lists. In order to output proper uv texture coordinates there are cases when vertices of a mesh have to be duplicated. The vertex duplication list allows the reader of the .X file to undo this duplication process.
Object hierarchy support by embedding mesh data within a 'Frame'
structure.
Automatic conversion of bitmap files to all major 2D bitmap file formats. Also, the
converter can resize the bitmaps so that they are a power-of-two and square
in size.
The converter can take any arbitrary 3D object (including those with n-sided
polygons and optional holes, bicubic patches or NURBS patches) and convert
them to optimized triangle meshes.
Since the DirectX file format does not allow for scale and offset values for each texture bitmap (as is provided by most rendering program’s material definitions), this converter incorporates a smart routine which adds redundant vertices to a polygon mesh and directly multiplies in the scale/offset values into the (u,v) texture coordinates.
Mesh Dialog Box Options:
File Type = ASCII, Binary
If the radio button is set to 'Binary' then the .X file will be written in
the binary file format. If set to 'ASCII' then the .X file will be written
in the ASCII file format.
Reverse Orientation of all Polygons
If this option is enabled (checkmarked) then the orientation of all polygons
will be reversed (the winding order of the faces will be reversed). This will
effectively reverse the direction of each polygon's geometric normal.
Flip Polygon Normals
If this option is enabled (checkmarked) then the direction of each vertex
normal (if any normals are output) will be flipped so that they point in the
opposite direction. This option should be enabled if the shading looks wrong
on the exported objects.
Output All Data As a Single Mesh Object
If this option is disabled (un-checkmarked), which is the default, then the
converter will output one or more 'Mesh' structures per file, each
corresponding to an object within the 3d database.
If this option is enabled (checkmarked) then the converter will output all object data to a single ‘Mesh’ structure. Note that enabling this option implies that the ‘Encapsulate Mesh Data in ‘Frame’ Hierarchy’ and the ‘Output Transformation Matrices With Each Frame’ options are disabled.
Allow Vertex Geometry Alteration for (u,v) Texture Coordinates
Due to a limitation of the DirectX file format polygon vertices have to be
duplicated in order to properly output the (u,v) texture coordinates. For
example, if a corner of two abutting polygons share the same vertex
coordinate but have two different (u,v) coordinates then this vertex
coordinate will have to be duplicated two in the exported DirectX file.
If this option is enabled (checkmarked) then the converter will properly
output (u,v) texture coordinates by duplicating (altering) the vertex
coordinate data. If this option is disabled (un-checkmarked) then the converter will not alter
the vertex coordinates and thus the (u,v) texture coordinate may or may not
be output properly.
NOTE: The destination program can undo this vertex duplication by way of the "VertexDuplicationIndices" which can be exported to the .X file when the "Output vertex duplication list" option is enabled. This is a new option for DirectX 8.
Output All Polygons As Triangles
If this option is enabled (checkmarked) then all polygons which have 4 or
more sides will be converted to triangles prior to output. Concave polygons
and polygons with holes will be properly triangulated.
Encapsulate Mesh Data in 'Frame' Hierarchy
If this option is enabled (checkmarked) then the converter will recreate
geometry hierarchy in the .X file by embedding each mesh structure within one
or more layered 'Frame' structures. Such a file should be loaded into
Direct3D using the 'Frame::Load' command.
If this checkbox is disabled then no 'Frame' or 'FrameTransformMatrix'
structures will be output. Such a file should be loaded into Direct3D using
the 'Mesh::Load' command.
Output Transformation Matrices With Each Frame
If this option is enabled (checkmarked) as well as the 'Encapsulate Mesh Data
in 'Frame' Hierarchy' option (explained above) then each mesh structure will
be preceeded by a transformation matrix which will transform the data from
the coordinate system of it's parent frame to the coordinate system of the
mesh's local frame.
If this option or the 'Encapsulate Mesh Data in 'Frame' Hierarchy' option is
disabled then all transformation matrices will be multiplied directly into
the vertex coordinates of each mesh and no matrices will be output to the
file.
Convert and Output Animation Data
If this option is enabled (checkmarked) then animation data will be output to the .X file. Such a file should be loaded into Direct3D using the ‘AnimationSet::Load’ command. Only a specific number of supported import formats can output animation data to the DirectX file. The program will optimize the data to remove redundant keyframes. This animation export capability is only available when running this export converter with Okino’s PolyTrans or NuGraf Rendering System software.
Note that enabling this option implies that the ‘Encapsulate Mesh Data in ‘Frame’ Hierarchy’ and the ‘Output Transformation Matrices With Each Frame’ options are enabled and that the ‘Output All Data As a Single Mesh Object’ option is disabled.
Method to Convert from Right-Handed Coordinate System to Left-Handed Coordinates
DirectX uses a left handed coordinate system whereas PolyTrans/NuGraf use a right handed coordinate system (as is common for most 3D file formats, except for Lightwave which is left handed as well). This drop-down box selects which method will be used during export to change from right-handed coordinates to left-handed coordinates.
Don't Do Anything
As its name implies, nothing is done to the exported data. In this case you may find that the exported scene looks incorrectly mirrored about the XY plane and that rotations are in the wrong direction.
Flip Z of Vectors and Reverse Angle of Quaternions
This is the most ideal option to enable, but not the default at this time. This option causes the Z coordinate of all vectors to be negated and the angle of all quaternion rotations to be reversed.
Flip Z of Top-Level Matrix
This option simply applies a -1 scale vector in Z to the top-level frame matrix in the file. This basically mirrors the entire scene about the XY plane. This works well except for custom programs which import .X files and expect that all coordinates and matrix frames be in LHCS; for the latter case go and enable the "Flip Z of Vectors and Reverse Angle of Quaternions" option.
'World' Scaling Factor
This number allows the exported geometry data to be scaled in size. Values less than 1.0
will make the 'world' smaller while values greater than 1.0 will make the
'world' larger. If after loading a .X file into a .X file viewer you cannot
see anything then try a scale value of 0.1, 0.01, 0.001, etc.
Line Terminator Type
This common option selects which line terminator is to be used for the ASCII
output file:
Files destined for DOS/PC machines should use CR/LF,
Files for UNIX machines should use LF, and
Files for Macintosh machines should use CR.
The default is specific to which machine this converter is presently
running on: CRLF for DOS/PC, LF for UNIX and CR for Macintosh. This option
normally does not have to be specified unless you will be using the exported
ASCII file on a different type of computer.
Bitmap Dialog Box Options:
Convert Foreign Bitmap Files to New File Format
If this checkbox is enabled then all 2d bitmap textures which are currently defined and
referenced by the internal NuGraf/PolyTrans database scene will be automatically tagged then
converted to a new user-specified 2d bitmap file format during export. The desired
format is chosen using the Bitmap File Format combo box. If the texture(s) cannot
be found in the location specified by the pathname prepended to the input texture
filename then the export converter will search for the texture(s) in all directories
specified in the 'Default Search Path' and the 'Texture Bitmaps Search Path' file search
paths (these can be modified by choosing the 'Preferences/Configure File Search Paths' menu item.
Bitmap File Format (Combo Box)
This combo box lists the destination bitmap file format.
Bitmap Depth (Bits/Pixel): 2, 4, 8, 24
These radio buttons determine the number of bits/pixel to write out to
the .bmp texture file (.ppm files are always 24 bits). The default is 24
bits. A color quantization algorithm will be used for the 2, 4 and 8
bits/pixel output formats.
Dimensions: X = #, Y = #
If the 'Convert Bitmap Files to .bmp or .ppm Format' option is enabled then
the following two drop-down list boxes determine the X and Y resolution for
the converted bitmap file(s):
No Change = Do not change the X or Y size
Closest = Use the next highest power-of-2 size
2, 4, 8, ... 256, 512 = Choose a specific size for the X or Y dimension
All texture bitmap images used by Direct3D must be a power-of-2 in size
(2, 4, 8, 16, etc.).
Material & Color Dialog Box Options:
Polygon Materials
If this option is enabled (checkmarked) then any material attributes assigned to individual polygons will be output to the .X file using the 'MeshMaterialList' structure.
Texture References
If this option is enabled (checkmarked) then any material which uses a bitmap texture will output a reference to the texture map using the 'TextureFilename' command.
Substitute White Face Color For Textured Faces
When texture mapping a polygon Direct3D first multiplies the polygon's face
color (the diffuse color) by the texture pixel value. This has the
unfortunate side effect of tinting the texture mapped surface and/or making
it darker. For example, if the current face color is black then the polygon
will appear black; if the current face color is blue then the texture mapped
polygon will be tinted blue.
If this option is enabled (checkmarked) then the face color for a polygon
will be set to white whenever that polygon has a texture map applied to it.
This will ensure that the texture mapped surface does not become tinted
and/or darker.
If this option is diabled (un-checkmarked) then the face color will reflect
its true color as exported from the database (it will not be changed to
white).
Always Set Face (Diffuse) Color to White
If this option is enabled (checkmarked) then the face color (diffuse color)
will always be output as white (1,1,1).
Always Set Specular Color to White
If this option is enabled (checkmarked) then the specular color will always
be output as white (1,1,1). The specular color controls the color and
intensity of the specular highlight.
Always Set Emissive Color to Black
If this option is enabled (checkmarked) then the emissive material color will
always be output as black (0,0,0).
Always Set Face's Alpha Value to 1 (Completely Opaque)
If this option is enabled (checkmarked) then the face color's alpha value
will always be output as 1.0 (completely opaque).
Face Alpha Color Change
These two parameters allow the alpha value of the face material color
(diffuse color) to be modified. If the current alpha value is less than the
'Max' parameter then the 'Delta' value will be added to it, else the alpha
value will not be modified. For example, if the alpha value is 0.3, the
'Delta' value is 0.4 and the 'Max' value is 1.0 then the export converter
will add 0.4 to 0.3 and output the alpha value as 0.7; however, if the 'Max'
value was set to 0.2 then nothing would change since the alpha value (of 0.3)
is not less than the 'Max' value.
Output Enables Dialog Box Options:
The check boxes inside the 'Output Enables' section control what type of data
will be output to the .x file:
Output Mesh Skin Weights
"Mesh skinning" is the process of deforming a single skin mesh with a skeleton (in the .X file the skeleton is represented by the frame matrices which define the pivot point and orientation of each invisible bone). The contribution of each bone of the skeleton to the deformation of a vertex in the mesh is controlled by vertex weights. If this option is enabled then a mesh will be bound to one of more "frames" in the .X file (which represent the bones or joints of the skeleton) via transformation matrices and weight values. This option is only valid if the source data has at least one mesh object bound to any number of other objects, null nodes or skeleton nodes in the scene (any object can be a deformer).
Output Skinned Meshes After Bones Have Been Output, and Re-attach to "World" Frame
Skinning works by having a mesh object reference one or more "bone" controlling objects in the scene. For DirectX these "bones" are just the transformation matrix of a frame. The ideal situation is to have the bone nodes (transform nodes) output first and then the skinned mesh last, since the skinned mesh makes references to the previously output bone node names. If this option is enabled (which is the default) then a two pass method will be used; in the first pass all the hierarchy, the transform nodes (including those which act as bones) and non-skinned meshes will be output. In the second pass the skinned meshes will be output, except this time they will be re-attached in the hierarchy to the "world" root node and not be inserted anywhere in the hierarchy. This latter stage of reconnecting the skinned meshes to the "world" is fine because their location in the hierarchy does not matter at all (during skinning only the location and animation of the "skeleton of bones" actually deform and move the skinned mesh into its final deformed state and location). If this option is disabled then the skinned meshes will be output in their normal hierarchy location.
Vertex Normals
If this option is enabled (checkmarked) then any normals that are assigned to polygon vertices
will be output to the X file using the 'MeshNormals' structure.
Vertex Colors
If this option is enabled (checkmarked) then any colors that are assigned to
polygon vertices will be output to the X file using the 'MeshVertexColors'
structure.
Vertex Duplication List
DirectX8 introduced a new template called a vertex duplication list. It specifies which vertices in a mesh had to be duplicated during the export process due to different adjacent materials at a polygon boundary. By using this list during import in the destination program the vertex duplication phase can be undone very easily.
Textures Coordinates
If this option is enabled (checkmarked) then any (u,v) texture coordinates that are assigned to
polygon vertices will be output to the .X file using the 'MeshTextureCoords' structure.
Flip 'v' Texture Coordinates (vertically)
If this option is enabled (checkmarked) then all 'v' texture mapping coordinates will be flipped (inverted) so that the texture maps will appear inverted when rendered using DirectX. It has been reported that DirectX versions 2.0 through 3.0 had a bug in them such that all texture maps were incorrectly inverted. Thus, models that appear correct in v2.0-v3.0 will appear inverted if rendered within newer versions of DirectX (such as v5.0). To solve this problem, simply enable this option for models exported to DirectX v5.0 or newer if the texture maps appear flipped vertically.
Include Templates in File
If this option is enabled (checkmarked) then 'templates' will be output to
the .X file. This is the default.
Use Absolute Paths For All Bitmap References
Inside a DirectX file a 2d bitmap texture can be applied to a material using the “TextureFilename” command whose argument is a filename to a BMP or PPM formatted bitmap image. If this option is enabled (checkmarked) then the filename will also include a complete file path to the file’s location (ie: “c:\images\carpet.bmp”). If this option is disabled (un-checkmarked) then no file path will prefix the filename (ie: “carpet.bmp” will be output).
Use New Export Directory As Bitmap File Path
If this option is enabled, and the ' Use Absolute Paths For All Bitmap References' option is enabled, then the texture map filename exported to the DirectX file will will be prepended with the same filepath as the directory where the DirectX file is being exported to. For example, if you are saving the new DirectX file to directory "c:\myfiles" then an exported texture filename will look like "c:\myfiles\carpet.bmp". If this option is disabled then NOTHING will be done to the exported bitmap filename. This is ideal if you have imported some 3D file which uses absolute texture filepaths and you wish to have these exact same filepaths exported to the DirectX file. So, if you imported a file with a filepath named "c:\texturesfiles\carpet.bmp" it will be exported to the DirectX file exactly the same with no changes.
Convert All File Paths To Use Forward Slashes
If this option is enabled (checkmarked) then all file paths on the bitmap filenames will use forward slash separators (ie: '/images/directx/brick.bmp') whereas if this option is un-checkmarked then the bitmap filenames will use backward slashes (ie: '\images\directx\brick.bmp'). Both methods have been tested with the Microsoft DirectX SDK and both are accepted equally.
Replace all Bitmap File Paths with this File Path
This option allows all bitmap references exported to the DirectX file to be prefixed with a new filepath. The 'Use Absolute Paths For All Bitmap References' option must also be enabled. This might be useful, for example, if all of your bitmap files are located in one specific directory or if you wish to change the prefix on the imported bitmap references. To choose the filepath press the “Browse” button. To disable this option, click on the checkbox again so that it comes un-checkmarked.
Animation Dialog Box Options:
Slow Down Animation by a Factor of #
This integer value allows the output animation keyframe data to be slowed down in time. This is accomplished by multiplying the keyframe time values by the specified integral value. Thus, a value of 2 will slow down the animation by a factor of 2. The default is 1.
Ticks Per Second
This combo box determines how many "ticks per second" the output animation will be scaled by.
DirectX keys are output by multiplying the frame time by (ticks-per-second / frames-per-second). The ticks-per-second is set by this combo box, and the frames-per-second is set by the current scene being exported. Most DirectX viewers use 3600 as the "ticks per scond", but it has been reported that some newer DirectX viewers have opted for the more sane 4800 ticks per second.
Fix up -180/180 degree flips from Euler key lists (Maintain Euler Curve Continuity)
This option fixes Euler rotation channels which flip back and forth between values close to 180 degrees and -180.0 degrees, from key to key, before they are exported to DirectX as quaternion rotation channels.. Normally this flipping will not pose a problem unless DirectX "slows down" an animation for previewing in slow motion, and does sub-key interpolation (in such cases the objects may appear to randomly spin in the wrong direction at specific keys).
Background Info:
Euler animation data (3 explicit X, Y and Z rotation channels) needs to be "resampled" from one mathematical format to another, Euler notation to quaternion notation, for DirectX export.
The resampling process first converts the Euler rotation value(s) at each keyframe to a 4x4 rotation matrix, and then the matrix is decomposed into explicit (X, Y, Z) Euler rotation angles, of the desired Euler order. The Euler angles will always be in the range -180 to 180 degrees.
The primary disadvantage of the traditional Euler decomposition method comes about when DirectX attempts to view the animation in a "slow motion" mode. Since two adjacent frames might have values of, say, -179.9 and 179.9 (or vice versa) on one of the Euler angles, the sub-frame interpolation between these values will result in a quick spin through 359.8(!) degrees, rather than the intended 0.2 degree change. When a "slow motion" mode is not in effect, the user will traditionally never see the sub-frame interpolated values because the -179.9 and 179.9 rotations are absolute and correct values (needing no further interpolation between them).
Problem example: if the exported Euler source rotations are 150.0 deg, 179.0, deg, 185.0 deg, 190.0 deg then after resampling the rotations will be 150.0 deg, 179.0 def, -175.0 deg, -170.0 deg. These are correct. However, file formats such as DirectX, during slow-motion playback where sub-frame interpolation is performed, will look at the 179.0 to -175.0 degree interval and create new interpolated values through a 354 degree rotation interval and not the shorter 6 degree rotation.
What This Option Does:
Enabling this option will allow an additional algorithm to be used which detects cases of "-180/180 degree Euler Flips" and attempts to fix them. This alternative algorithm will take the previous frame of animation into account when performing rotation resampling. It will attempt to decompose the rotation into a equivalent set of Euler angles which represents the smallest Euler-space change of values. This makes the algorithm very good for preventing -180/180 discontinuities in the Euler animation curves. This allows "slow motion" sub-frame interpolation to function as ideally expected.
One possible down-side to this alternative algorithm is that Euler angles are free to "drift" away from the normal -180/180 range. Let us suppose you have an animation of a spinning top. Under the traditional algorithm, the top might spin from 0 to 180, then a discontinuity effect occurs, causing the next frames to go from -180 to 0 to 180, and so forth. With this option enabled, the top would spin from 0 to 180, then from 180 to 360 to 540, and so forth. There are hypothetical scenarios where users might not want that to happen. If that is the case, disable this option to ensure that all angles are clamped to the -180/180 range.
Modify Common Animation Export Options
Pressing this button will display the 'Common Animation Export Options' dialog box. This
dialog box controls how internal animation data is optionally re-sampled during its
export to a DirectX file. These export options are most important for properly exporting
animation data to DirectX.
Usage Notes:
If the 'Encapsulate Mesh Data' option is enabled then the .X file created
with this export converter should be loaded using the 'Frame::Load' command.
If the 'Encapsulate Mesh Data' option is disabled then the .X file created
with this export converter should be loaded using the 'Mesh::Load' command.
If the .X file contains animation data then it should be loaded with the
'AnimationSet::Load' command.
Mesh Dialog Box Options:
