[Closed] How does the paint blend weights function work?

would help if you post the function call name.

<Skin>.paintBlendMode BooleanClass default:false

think this might be what you are looking for, though it’s a hefty plugin to wade through… the rest can be found in maxsdk\samples\modifiers\bonesdef

void BonesDefMod::ApplyPaintWeights(BOOL alt, INode *incNode)
	{
//5.1.03
	BOOL blendMode = FALSE;
	pblock_param->GetValue(skin_paintblendmode,0,blendMode,FOREVER);

	INode *node = NULL;
	for (int i =0;i < painterData.Count(); i++)
		{
		painterData[i].alt = alt;
		if (incNode == NULL)
			node = painterData[i].node;
		else node = incNode;
		if (node == painterData[i].node)
			{
			BoneModData *bmd = painterData[i].bmd;
			int count;
			float *str = pPainterInterface->RetrievePointGatherStr(node, count);
			int *isMirror = pPainterInterface->RetrievePointGatherIsMirror(node, count);

			BitArray excludedVerts;
			BOOL useExclusion = FALSE;
			if ((ModeBoneIndex >= 0) && (ModeBoneIndex < bmd->exclusionList.Count()))
			{
				if (bmd->exclusionList[ModeBoneIndex])
				{								
					excludedVerts.SetSize(count);
					excludedVerts.ClearAll();
					useExclusion = TRUE;
					for (int j = 0; j < bmd->exclusionList[ModeBoneIndex]->Count(); j++)
					{
						int index = bmd->exclusionList[ModeBoneIndex]->Vertex(j);
						if (index < excludedVerts.GetSize())
							excludedVerts.Set(index,TRUE);
					}
				}
			}

			if ((mirrorIndex >= 0) && (mirrorIndex < bmd->exclusionList.Count()))
			{
				if ((mirrorIndex != -1) && bmd->exclusionList[mirrorIndex])
				{			
					if (excludedVerts.GetSize() != count)
					{
						excludedVerts.SetSize(count);
						excludedVerts.ClearAll();
					}
					useExclusion = TRUE;
					for (int j = 0; j < bmd->exclusionList[mirrorIndex]->Count(); j++)
					{
						int index = bmd->exclusionList[mirrorIndex]->Vertex(j);
						if (index < excludedVerts.GetSize())
							excludedVerts.Set(index,TRUE);
					}
				}
			}
			for (int j =0; j < count; j++)
				{

				BOOL skip = FALSE;
				if (useExclusion)
				{
					if (excludedVerts[j])
						skip = TRUE;
				}
				if ((str[j] != 0.0f) && (!skip))
					{
//get original amount
					float amount = 0.0f;
					int boneID = ModeBoneIndex;
					if (isMirror[j] == MIRRRORED) boneID = mirrorIndex;

					if(boneID != -1)
						{
//add to it str
						for (int k =0; k < bmd->VertexData[j]->WeightCount(); k++)
							{
							if (bmd->VertexData[j]->GetBoneIndex(k) == boneID)
								{
									amount = bmd->VertexData[j]->GetNormalizedWeight(k);			
									k = bmd->VertexData[j]->WeightCount();
								}
							}
//5.1.03
						if (blendMode &&  bmd->blurredWeights.Count() != 0)
							{
								float blurAmount = bmd->blurredWeights[j];
								 amount += (bmd->blurredWeights[j] - amount) * str[j];
							 }
						  else
							 {
							if (alt)
								amount -= str[j];
							else 
								amount += str[j];
							if (amount > 1.0f) amount = 1.0f;
							if (amount < 0.0f) amount = 0.0f;
							}

						
//set it back
						updateDialogs = FALSE;
						SetVertex(bmd, j, boneID, amount);
						updateDialogs = TRUE;
						}
					}
				}

			}
		}
	}

silly page

got it to work thanks!