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 Programming MEL Scripts, Expressions & Programming Related Topics

 08-06-2020, 08:41 AM #1 brandaoSA BrandaoSA   Join Date: Jun 2020 Posts: 1 NCloth set alpha based on vertex position I am trying the following setup: NCloth material has a) or a initial state, b) a copy of mesh in initial state NCloth is tearable and will split / explode in many places which should alpha/fade based on some "life" parameter, or in this case, the vertices current distances from their initial position. I am using Arnold as renderer and my attempt is to use vertex color driven by expression comparing every frame every vertex from its original position and then remapping this distance to work as transparency channel on the object texture. I am very far from achieving any promising effect after 3 -4 hours and I am using just a simple cube as test. Anyone has any experience about similar situation for advising? (have no idea what happened to code formatting below - you have to select the text in order to see it...) Code: ``` int \$vtxCount[] = `polyEvaluate -v pCube1`; for(\$i = 0; \$i < \$vtxCount[0] ; \$i++){ float \$c1[] = `pointPosition -l pCube1.vtx[\$i]`; float \$o1[] = `pointPosition -l pCube2.vtx[\$i]`; float \$d1 = sqrt( (\$o1[0] - \$c1[0]) * (\$o1[0] - \$c1[0]) + (\$o1[1] - \$c1[1]) * (\$o1[1] - \$c1[1]) + (\$o1[2] - \$c1[2]) * (\$o1[2] - \$c1[2])); if (\$d1 > 0.01) { //setAttr remapColor1.inputMin = \$d1; \$d1 \$d1 \$d1 ; works only when I press "evaluate button" //direct connection remapColor1.inputMin = \$d1; } }```

 Tags arnold , ncloth , vertex color