Displaying mesh using DirectX 9 - Mesh differences

Question

This is my program to display a .x mesh. I am able to display the mesh tiger.x but not able to display ball.x. What is the difference between the two meshes? Is there something I should handle in the code? But I am able to view both the meshes using standard mesh viewers like the one which come with DirectX SDK.

Thanks.

Answer 1

but not able to display ball.x.

The question is unclear. Does the mesh load? Does it contain vertices/faces? Or maybe it crashes app? Or loading fails?

What is the difference between the two meshes?

The difference is that the second mesh (ball.x) doesn't include "templates".

I.e. this part:

template Header {
 <3D82AB43-62DA-11cf-AB39-0020AF71E433>
 WORD major;
 WORD minor;
 DWORD flags;
}

template Vector {
 <3D82AB5E-62DA-11cf-AB39-0020AF71E433>
 FLOAT x;
 FLOAT y;
 FLOAT z;
}

template Coords2d {
 <F6F23F44-7686-11cf-8F52-0040333594A3>
 FLOAT u;
 FLOAT v;
}

template Matrix4x4 {
 <F6F23F45-7686-11cf-8F52-0040333594A3>
 array FLOAT matrix[16];
}

template ColorRGBA {
 <35FF44E0-6C7C-11cf-8F52-0040333594A3>
 FLOAT red;
 FLOAT green;
 FLOAT blue;
 FLOAT alpha;
}

template ColorRGB {
 <D3E16E81-7835-11cf-8F52-0040333594A3>
 FLOAT red;
 FLOAT green;
 FLOAT blue;
}

template IndexedColor {
 <1630B820-7842-11cf-8F52-0040333594A3>
 DWORD index;
 ColorRGBA indexColor;
}

template Boolean {
 <4885AE61-78E8-11cf-8F52-0040333594A3>
 WORD truefalse;
}

template Boolean2d {
 <4885AE63-78E8-11cf-8F52-0040333594A3>
 Boolean u;
 Boolean v;
}

template MaterialWrap {
 <4885AE60-78E8-11cf-8F52-0040333594A3>
 Boolean u;
 Boolean v;
}

template TextureFilename {
 <A42790E1-7810-11cf-8F52-0040333594A3>
 STRING filename;
}

template Material {
 <3D82AB4D-62DA-11cf-AB39-0020AF71E433>
 ColorRGBA faceColor;
 FLOAT power;
 ColorRGB specularColor;
 ColorRGB emissiveColor;
 [...]
}

template MeshFace {
 <3D82AB5F-62DA-11cf-AB39-0020AF71E433>
 DWORD nFaceVertexIndices;
 array DWORD faceVertexIndices[nFaceVertexIndices];
}

template MeshFaceWraps {
 <4885AE62-78E8-11cf-8F52-0040333594A3>
 DWORD nFaceWrapValues;
 Boolean2d faceWrapValues;
}

template MeshTextureCoords {
 <F6F23F40-7686-11cf-8F52-0040333594A3>
 DWORD nTextureCoords;
 array Coords2d textureCoords[nTextureCoords];
}

template MeshMaterialList {
 <F6F23F42-7686-11cf-8F52-0040333594A3>
 DWORD nMaterials;
 DWORD nFaceIndexes;
 array DWORD faceIndexes[nFaceIndexes];
 [Material]
}

template MeshNormals {
 <F6F23F43-7686-11cf-8F52-0040333594A3>
 DWORD nNormals;
 array Vector normals[nNormals];
 DWORD nFaceNormals;
 array MeshFace faceNormals[nFaceNormals];
}

template MeshVertexColors {
 <1630B821-7842-11cf-8F52-0040333594A3>
 DWORD nVertexColors;
 array IndexedColor vertexColors[nVertexColors];
}

template Mesh {
 <3D82AB44-62DA-11cf-AB39-0020AF71E433>
 DWORD nVertices;
 array Vector vertices[nVertices];
 DWORD nFaces;
 array MeshFace faces[nFaces];
 [...]
}

template FrameTransformMatrix {
 <F6F23F41-7686-11cf-8F52-0040333594A3>
 Matrix4x4 frameMatrix;
}

I.e. templates/structure declarations.

Also, in ball.x mesh is a part of hierarchy of Frames. In tiger.x it isn't, and is stored on top level of hierarchy.

It's been a while since I last used *.x file directly, but as far as I know, you'll need to include templates for all "non standard" templates into file. i.e. if file uses an object with template that wasn't registred using RegisterTemplates method of ID3DXFile or IDirectXFile, then the file won't load if template isn't written at the beginning of file. Try adding template definitions for every suspicious structure in ball.x , until you find the culprit . I'd start with "Header".

If the problem is because of hierarchy, you'll need to try another loading method.

using standard mesh viewers like the one which come with DirectX SDK.

AFAIK, mesh viewer comes with source code. Read the source and see how it works.

Answer 2

The mesh does not have any issue but the view. It was too zoomed in to display the image. I projected the image using the following matrix and was able to view the mesh properly.

//Set Projection
D3DXMATRIXA16 matProj(1.0,0.0,0.0,0.0,
                      0.0,1.0,0.0,0.0,
                      0.0,0.0,1.0,0.0,
                      0.0,0.0,0.0,150.0);