Assign Vertex Color Map to shader [SOLVED]

On 21/05/2018 at 08:08, xxxxxxxx wrote:

User Information:
Cinema 4D Version:   18+ 
Platform:   Windows  ; Mac  ;  
Language(s) :     C++  ;

---------
Hi,

I want to assign a vertex color tag to a vertex map shader.

Here is the code I am using:

  
		// allocate the Vertex Map shader
		AutoAlloc<BaseShader> vertexMapShader(Xvertexmap);
		if (!vertexMapShader)
			return false;
  
		// retrieve the BaseContainer of the Vertex Map shader
		BaseContainer* vertexMapShaderBC = vertexMapShader->GetDataInstance();
		if (!vertexMapShaderBC)
			return false;
  
		// The Vertex Color tag is vctag
		GeData gd;
		vertexMapShaderBC->GetParameter(GV_VERTEXCOLORMAP_INPUT_TAG, gd); // ---->this is where the crash happens
		
		BaseLink *myLink = gd.GetBaseLink();
		myLink->SetLink(vctag);
  
  

Any idea why it does not work?

On 22/05/2018 at 05:32, xxxxxxxx wrote:

Hi Salozo,

First of all, I'm not sure to understand, from where you get the ID GV_VERTEXCOLORMAP_INPUT_TAG, to know an ID you can simply drag and drop the parameter in the console.
Another thing is actually you should use Set/GetParameter in the C4DAtom(the shader in your case) itself and not on the BaseCcontainer.
In other hands here an example how to set up a link.

		// allocate the Vertex Map shader
		AutoAlloc<BaseShader> vertexMapShader(Xvertexmap);
		if (!vertexMapShader)
			return false;
  
		// allocate the Vertex Map
		AutoAlloc<BaseTag> vertexMap(Tvertexcolor);
		if (!vertexMap)
			return false;
  
		// allocate the Vertex Map
		AutoAlloc<BaseLink> link;
		if (!link)
			return false;
  
		link->SetLink(vertexMap.Release()); // I use release, since vertexMap is an AutoAlloc object, so you need to release it in order to let the ownership of the vertexMap I created to c4d.
		vertexMapShader->SetParameter(SLA_DIRTY_VMAP_OBJECT, GeData(link), DESCFLAGS_SET_0);

Hope it helps, if you have any question please do not hesitate!

Cheers,
Maxime

On 22/05/2018 at 07:59, xxxxxxxx wrote:

Thank you for your help Maxime. It works as it should now.