Exit GJK early if geom distance doesn't need to be recovered.

PiperOrigin-RevId: 672334991
Change-Id: I4af582c799140ccf3ac4d51952e547b08ab5d55e

src/engine/engine_collision_gjk.c

@@ -125,6 +125,7 @@ static mjtNum gjk(mjCCDStatus* status, mjCCDObj* obj1, mjCCDObj* obj2) {
   mjtNum* x2_k = status->x2;
   mju_sub3(x_k, x1_k, x2_k);
   mjtNum epsilon = status->tolerance * status->tolerance;
+  int get_dist = status->has_distances;
 
 // if both geoms are discrete, finite convergence is guaranteed; set tolerance to 0
   if (discreteGeoms(obj1, obj2)) {
@@ -141,6 +142,11 @@ static mjtNum gjk(mjCCDStatus* status, mjCCDObj* obj1, mjCCDObj* obj2) {
     gjkSupport(s1, s2, obj1, obj2, x_k);
     mju_sub3(s_k, s1, s2);
 
+    // return early if geom distance isn't needed
+    if (!get_dist && mju_dot3(x_k, s_k) > 0) {
+      return mjMAXVAL;
+    }
+
     // the stopping criteria relies on the Frank-Wolfe duality gap given by
     //  |f(x_k) - f(x_min)|^2 <= < grad f(x_k), (x_k - s_k) >
     mjtNum diff[3];
@@ -1116,6 +1122,8 @@ mjtNum mjc_ccd(const mjCCDConfig* config, mjCCDStatus* status, mjCCDObj* obj1, m
   status->epa_iterations = -1;
   status->tolerance = config->tolerance;
   status->max_iterations = config->max_iterations;
+  status->has_contacts = config->contacts;
+  status->has_distances = config->distances;
 
   mjtNum dist = gjk(status, obj1, obj2);
 

src/engine/engine_collision_gjk.h

@@ -40,6 +40,8 @@ struct _mjCCDStatus {
   // configurations used
   int max_iterations;         // the maximum number of iterations for GJK and EPA
   mjtNum tolerance;           // tolerance used by GJK and EPA
+  int has_contacts;           // set to true if attempted to recover contact (pendetration) info
+  int has_distances;          // set to true if attempted to recover distance info
 
   // statistics for debugging purposes
   int gjk_iterations;         // number of iterations that GJK ran