I got generated Cube to .obj file from Blender. Like this:
o Cube_Cube.001
v -1.000000 -1.000000 -1.000000
v 1.000000 -1.000000 -1.000000
v 1.000000 -1.000000 1.000000
v -1.000000 -1.000000 1.000000
v -1.000000 1.000000 -1.000000
v 1.000000 1.000000 -1.000000
v 1.000000 1.000000 1.000000
v -1.000000 1.000000 1.000000
vn 0.000000 0.000000 -1.000000
vn 1.000000 0.000000 0.000000
vn 0.000000 0.000000 1.000000
vn -1.000000 0.000000 0.000000
vn 0.000000 -1.000000 0.000000
vn 0.000000 1.000000 0.000000
usemtl None
s off
f 5//1 6//1 1//1
f 6//2 7//2 2//2
f 7//3 8//3 3//3
f 8//4 5//4 4//4
f 1//5 2//5 4//5
f 8//6 7//6 5//6
f 6//1 2//1 1//1
f 7//2 3//2 2//2
f 8//3 4//3 3//3
f 5//4 1//4 4//4
f 2//5 3//5 4//5
f 7//6 6//6 5//6
I load vertices as they are line by line and store them in array. Then indicies (lines starting with 'f' as I suppose) stored to Indicies array so something like {4, 5, 0, 6, 7 ...} (decreased by 1 because of position of vertex in array) and then create array VertexPositionColors.
But when I draw primitives the cube is wierdly deformed. Draw method:
GraphicsDevice.Clear(Color.CornflowerBlue);
GraphicsDevice.DepthStencilState = DepthStencilState.Default;
effect.World = world;
effect.View = view;
effect.Projection = projection;
effect.VertexColorEnabled = true;
RasterizerState rs = new RasterizerState();
rs.CullMode = CullMode.None;
rs.FillMode = FillMode.WireFrame;
GraphicsDevice.RasterizerState = rs;
foreach (EffectPass pass in effect.CurrentTechnique.Passes)
{
pass.Apply();
GraphicsDevice.DrawUserIndexedPrimitives(PrimitiveType.TriangleList, model.VertexPositionColors, 0, model.VertexPositionColors.Length, model.Indicies, 0, model.Indicies.Length / 3, model.VertexDeclarations);
}
output https://i.sstatic.net/ZRROi.png
[SOLUTION] Check what your import algorithm generates. My indices were messed up because of bad iteration. My bad :)
I would recommend using FBX and the standard XNA content importer system. This streamlines the process so you don't even have to write an importer; you just point XNA at your content and can draw it in very few, very simple commands. Writing an importer yourself is a good exercise, but on the XNA platform it is not necessary.
