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Jannis
03-07-2006, 12:55 AM
first, is there a way to access with expresso the input of texture on a material node and further more can you access deeper to the options of a shader like say a gradient? Just like you could in a shader tree. I don't understand why there is a texture output in all the channels but not an input?

second is there a way to load the properties of a keyframe in expresso so that you can access the key properties as shown in the Attribute manager?

thanks

Rantin Al
03-20-2006, 12:37 AM
Hi Jannis,
Just make user Data fields and load them as usual.
Quick sample with Null, texture and two data fields.
Drag sub-items from the reference fields in the AM into the XPresso editor.

HTH, Al.
(Working through your CDs just now. :thumbsup: )

Jannis
03-20-2006, 09:55 AM
sorry, but I can't understand from this example how it works.

What I am asking is this,

The input in the Color channel for a material is of a data type Vector

The output for the data type Texture is String.

In the material node there is no other input Data type other than vector. That means that there is no way possible to connect a Data type of String to a Data type of Vector.

So, is there any way in which you can make that connection?

What is crazy is that you find both a Texture output in the material node of data type link and a Brightness Data type Real. So you can output textures but to what? What use is such an uotput if you can't output it to a material? Maybe I don't understand a hidden function here, but this is a real strange one.

Thanks for replying and I am glad you are working through my tutorials, hope they are useful to you

Srek
03-20-2006, 10:51 AM
You are trying to use Xpresso as a node based material system which it isn't.
You can link several parameters to create dependencies between materials and shaders but not much more.
You can drag any shader into the Xpresso editor by draging the small icon from the AM.

The input in the Color channel for a material is of a data type Vector
This is simply the color value that is used if no texture is used

The output for the data type Texture is String.
If you use a bitmap this string holds the filename.

In the material node there is no other input Data type other than vector. That means that there is no way possible to connect a Data type of String to a Data type of Vector.
You can use the bitmap node to read single pixel from a bitmap file

So, is there any way in which you can make that connection?
Not in the way you want to use it.

Cheers
Björn

Jannis
03-20-2006, 11:32 AM
You can drag any shader into the Xpresso editor by draging the small icon from the AM.



Thanks, thats all I needed.

Rantin this is also what you meant, sorry I didn't understand this.

By the way, is this in the manual? I never knew this.

Rantin Al
03-20-2006, 01:37 PM
Hi Jannis,

Sorry it was so brief and a bit misleading. It was kind of late when I posted.
I didn't fully understand what you intended as final purpose and just fired it up to show that some material parameters could be brought into Xpresso as a quick example.

No, I didn't find anything about using this in the manual.
I was building an Xpresso slider controller for setting up the Sub-Surface Scattering settings in a shader.

Cheers, Al.

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