Add mjmMaterial and mjmFrame to C API.

PiperOrigin-RevId: 606191307
Change-Id: Iaf43f81522029002b28bba14ea046b1c968ab2e7

src/user/user_init.cc

@@ -38,6 +38,16 @@ void mjm_defaultBody(mjmBody& body) {
 
 
 
+// default frame attributes
+void mjm_defaultFrame(mjmFrame& frame) {
+  memset(&frame, 0, sizeof(mjmFrame));
+  mju_zero3(frame.pos);
+  mjuu_setvec(frame.quat, 1, 0, 0, 0);
+  frame.alt.axisangle[0] = frame.alt.xyaxes[0] = frame.alt.zaxis[0] = frame.alt.euler[0] = mjNAN;
+}
+
+
+
 // default joint attributes
 void mjm_defaultJoint(mjmJoint& joint) {
   memset(&joint, 0, sizeof(mjmJoint));
@@ -157,6 +167,20 @@ void mjm_defaultLight(mjmLight& light) {
 
 
 
+// Default material attributes.
+void mjm_defaultMaterial(mjmMaterial& material) {
+  memset(&material, 0, sizeof(mjmMaterial));
+  material.texuniform = false;
+  material.texrepeat[0] = material.texrepeat[1] = 1;
+  material.emission = 0;
+  material.specular = 0.5;
+  material.shininess = 0.5;
+  material.reflectance = 0;
+  material.rgba[0] = material.rgba[1] = material.rgba[2] = material.rgba[3] = 1;
+}
+
+
+
 // default equality attributes
 void mjm_defaultEquality(mjmEquality& equality) {
   memset(&equality, 0, sizeof(mjmEquality));