Add visualisation groups to skins.

PiperOrigin-RevId: 458441645
Change-Id: I14324e8efda5142b2718a5cc9215228c7556dbf7

src/user/user_composite.cc

@@ -67,6 +67,7 @@ mjCComposite::mjCComposite(void) {
   mjuu_setvec(skinrgba, 1, 1, 1, 1);
   skininflate = 0;
   skinsubgrid = 0;
+  skingroup = 0;
 
   // clear add flags
   for (int i=0; i<mjNCOMPKINDS; i++) {
@@ -1053,6 +1054,7 @@ void mjCComposite::MakeSkin2(mjCModel* model) {
   skin->material = skinmaterial;
   mjuu_copyvec(skin->rgba, skinrgba, 4);
   skin->inflate = skininflate;
+  skin->group = skingroup;
 
   // populate mesh: two sides
   for (int i=0; i<2; i++) {
@@ -1473,6 +1475,7 @@ void mjCComposite::MakeSkin2Subgrid(mjCModel* model) {
   skin->material = skinmaterial;
   mjuu_copyvec(skin->rgba, skinrgba, 4);
   skin->inflate = skininflate;
+  skin->group = skingroup;
 
   // populate mesh: two sides
   mjtNum S = spacing/(1+skinsubgrid);
@@ -1643,6 +1646,7 @@ void mjCComposite::MakeSkin3(mjCModel* model) {
   skin->material = skinmaterial;
   mjuu_copyvec(skin->rgba, skinrgba, 4);
   skin->inflate = skininflate;
+  skin->group = skingroup;
 
   // box
   if (type==mjCOMPTYPE_BOX) {

src/user/user_composite.h

@@ -94,6 +94,7 @@ class mjCComposite {
   float skinrgba[4];              // skin rgba
   float skininflate;              // inflate skin
   int skinsubgrid;                // number of skin subgrid points; 0: none (2D only)
+  int skingroup;                  // skin group of the composite object
 
   // element options
   bool add[mjNCOMPKINDS];         // add element

src/user/user_mesh.cc

@@ -1408,6 +1408,7 @@ mjCSkin::mjCSkin(mjCModel* _model) {
   rgba[0] = rgba[1] = rgba[2] = 0.5f;
   rgba[3] = 1.0f;
   inflate = 0;
+  group = 0;
 
   vert.clear();
   texcoord.clear();
@@ -1530,7 +1531,6 @@ void mjCSkin::Compile(const mjVFS* vfs) {
       throw mjCError(this, "unkown material '%s' in skin", material.c_str());
   }
 
-
   // set total vertex weights to 0
   vector<float> vw;
   size_t nvert = vert.size()/3;

src/user/user_model.cc

@@ -1628,6 +1628,7 @@ void mjCModel::CopyObjects(mjModel* m) {
     // set fields
     m->skin_matid[i] = psk->matid;
     copyvec(m->skin_rgba+4*i, psk->rgba, 4);
+    m->skin_group[i] = psk->group;
     m->skin_inflate[i] = psk->inflate;
     m->skin_vertadr[i] = vert_adr;
     m->skin_vertnum[i] = psk->vert.size()/3;

src/user/user_objects.h

@@ -504,6 +504,7 @@ class mjCSkin: public mjCBase {
   std::string material;               // name of material used for rendering
   float rgba[4];                      // rgba when material is omitted
   float inflate;                      // inflate in normal direction
+  int group;                          // group for visualization
 
   // mesh
   std::vector<float> vert;            // vertex positions