6 replies to this topic

[vinnyhalts]

Hi, I've been trying to wrap my head around this for a few days, and there is a small amount of relevant information about this on the internet.

 

How does BasicEffect get the texture name stored in a model's data? It seems like it is in the model processor, so I know I would need to write a custom one.

 

I just need to know: How do I get the texture inside a model? XNA's Basiceffect can draw one texture per mesh (for example, the tank, or dude), but how does it get that texture name?

 

If anyone knows, it would be very helpful, thanks!

[GuardianX]

Not sure if I got your question right. Texture name is stored inside model description file. For example take a look at wavefront obj format.

I just generated textured cube in 3D max and exported it in .obj format: 

 

.mtl file, containing information about materials:

 

# 3ds Max Wavefront OBJ Exporter v0.97b - (c)2007 guruware
# File Created: 19.03.2013 23:38:23


newmtl 01___Default
Ns 10.0000
Ni 1.5000
d 1.0000
Tr 0.0000
Tf 1.0000 1.0000 1.0000 
illum 2
Ka 0.5882 0.5882 0.5882
Kd 0.5882 0.5882 0.5882
Ks 0.0000 0.0000 0.0000
Ke 0.0000 0.0000 0.0000
map_Ka C:\Users\user\Documents\3dsMax\sceneassets\images\BARK5.jpg
map_Kd C:\Users\user\Documents\3dsMax\sceneassets\images\BARK5.jpg
 

 

 

.obj file, containing geometry:

 

# 3ds Max Wavefront OBJ Exporter v0.97b - (c)2007 guruware
# File Created: 19.03.2013 23:38:23


mtllib 1234.mtl


#
# object Box001
#


v  -19.8428 0.0000 20.1116
v  -19.8428 0.0000 -20.1797
v  19.1013 0.0000 -20.1797
v  19.1013 0.0000 20.1116
v  -19.8428 35.8199 20.1116
v  19.1013 35.8199 20.1116
v  19.1013 35.8199 -20.1797
v  -19.8428 35.8199 -20.1797
# 8 vertices


vn 0.0000 -1.0000 -0.0000
vn 0.0000 1.0000 -0.0000
vn 0.0000 0.0000 1.0000
vn 1.0000 0.0000 -0.0000
vn 0.0000 0.0000 -1.0000
vn -1.0000 0.0000 -0.0000
# 6 vertex normals


vt 1.0000 0.0000 0.0000
vt 1.0000 1.0000 0.0000
vt 0.0000 1.0000 0.0000
vt 0.0000 0.0000 0.0000
# 4 texture coords


g Box001
usemtl 01___Default
f 1/1/1 2/2/1 3/3/1 
f 3/3/1 4/4/1 1/1/1 
f 5/4/2 6/1/2 7/2/2 
f 7/2/2 8/3/2 5/4/2 
f 1/4/3 4/1/3 6/2/3 
f 6/2/3 5/3/3 1/4/3 
f 4/4/4 3/1/4 7/2/4 
f 7/2/4 6/3/4 4/4/4 
f 3/4/5 2/1/5 8/2/5 
f 8/2/5 7/3/5 3/4/5 
f 2/4/6 1/1/6 5/2/6 
f 5/2/6 8/3/6 2/4/6 
# 12 faces
 

As you can see, object consists out of 12 faces, which use 01___Default material, described in .mtl file.

 

 

[vinnyhalts]

Not sure if I got your question right. Texture name is stored inside model description file. For example take a look at wavefront obj format.

I just generated textured cube in 3D max and exported it in .obj format: 

scene.png

 

.mtl file, containing information about materials:

 

# 3ds Max Wavefront OBJ Exporter v0.97b - (c)2007 guruware
# File Created: 19.03.2013 23:38:23


newmtl 01___Default
Ns 10.0000
Ni 1.5000
d 1.0000
Tr 0.0000
Tf 1.0000 1.0000 1.0000 
illum 2
Ka 0.5882 0.5882 0.5882
Kd 0.5882 0.5882 0.5882
Ks 0.0000 0.0000 0.0000
Ke 0.0000 0.0000 0.0000
map_Ka C:\Users\user\Documents\3dsMax\sceneassets\images\BARK5.jpg
map_Kd C:\Users\user\Documents\3dsMax\sceneassets\images\BARK5.jpg
 

 

 

.obj file, containing geometry:

 

# 3ds Max Wavefront OBJ Exporter v0.97b - (c)2007 guruware
# File Created: 19.03.2013 23:38:23


mtllib 1234.mtl


#
# object Box001
#


v  -19.8428 0.0000 20.1116
v  -19.8428 0.0000 -20.1797
v  19.1013 0.0000 -20.1797
v  19.1013 0.0000 20.1116
v  -19.8428 35.8199 20.1116
v  19.1013 35.8199 20.1116
v  19.1013 35.8199 -20.1797
v  -19.8428 35.8199 -20.1797
# 8 vertices


vn 0.0000 -1.0000 -0.0000
vn 0.0000 1.0000 -0.0000
vn 0.0000 0.0000 1.0000
vn 1.0000 0.0000 -0.0000
vn 0.0000 0.0000 -1.0000
vn -1.0000 0.0000 -0.0000
# 6 vertex normals


vt 1.0000 0.0000 0.0000
vt 1.0000 1.0000 0.0000
vt 0.0000 1.0000 0.0000
vt 0.0000 0.0000 0.0000
# 4 texture coords


g Box001
usemtl 01___Default
f 1/1/1 2/2/1 3/3/1 
f 3/3/1 4/4/1 1/1/1 
f 5/4/2 6/1/2 7/2/2 
f 7/2/2 8/3/2 5/4/2 
f 1/4/3 4/1/3 6/2/3 
f 6/2/3 5/3/3 1/4/3 
f 4/4/4 3/1/4 7/2/4 
f 7/2/4 6/3/4 4/4/4 
f 3/4/5 2/1/5 8/2/5 
f 8/2/5 7/3/5 3/4/5 
f 2/4/6 1/1/6 5/2/6 
f 5/2/6 8/3/6 2/4/6 
# 12 faces
 

As you can see, object consists out of 12 faces, which use 01___Default material, described in .mtl file.

Right, thank you for replying. I am actually trying to get the texture data from the model, but inside XNA. Similar to how Basiceffect does it.

[phil_t]

I'm assuming you want to do this in the content pipeline (doing it at runtime is easy, just grab it off the BasicEffect attached to the model mesh).

Have a look at the following sample:
http://xbox.create.msdn.com/en-US/education/catalog/sample/custom_model_effect

It shows how to get the texture in the material processor.

[vinnyhalts]

I'm assuming you want to do this in the content pipeline (doing it at runtime is easy, just grab it off the BasicEffect attached to the model mesh).

Have a look at the following sample:
http://xbox.create.msdn.com/en-US/education/catalog/sample/custom_model_effect

It shows how to get the texture in the material processor.

Thanks, but, this does not extract the texture from the model's data.

 

How would I grab the texture from BasicEffect at runtime?

[phil_t]

Thanks, but, this does not extract the texture from the model's data.

 

It does this: 

 

            // Copy texture data across from the original material.
            BasicMaterialContent basicMaterial = (BasicMaterialContent)input;

            if (basicMaterial.Texture != null)
            {
                customMaterial.Textures.Add("Texture", basicMaterial.Texture);
                customMaterial.OpaqueData.Add("TextureEnabled", true);
            }

 

 

That lets you get the texture to put in a custom effect. What exactly are you trying to accomplish?

 

It looks like you can also get this in the ModelProcessor in ConvertMaterial. The MaterialContent contains a Textures member.

How would I grab the texture from BasicEffect at runtime?

 

 

Cast the Effect objects (on ModelMeshPart or ModelMesh) to BasicEffect. This will succeed assuming you aren't using a custom material. Then get the Texture property.

[vinnyhalts]

Thanks, but, this does not extract the texture from the model's data.

 

It does this: 

 

            // Copy texture data across from the original material.
            BasicMaterialContent basicMaterial = (BasicMaterialContent)input;

            if (basicMaterial.Texture != null)
            {
                customMaterial.Textures.Add("Texture", basicMaterial.Texture);
                customMaterial.OpaqueData.Add("TextureEnabled", true);
            }

 

 

That lets you get the texture to put in a custom effect. What exactly are you trying to accomplish?

 

It looks like you can also get this in the ModelProcessor in ConvertMaterial. The MaterialContent contains a Textures member.

>How would I grab the texture from BasicEffect at runtime?

 

 

Cast the Effect objects (on ModelMeshPart or ModelMesh) to BasicEffect. This will succeed assuming you aren't using a custom material. Then get the Texture property.

 

Thank you, I'll try using one of these in a bit.