Change MuJoCo engine source code function-spacing convention from 3 blank lines to 2

PiperOrigin-RevId: 813754244
Change-Id: I6836e41c3b021cb727e922c25c60f629b9814c93

Author: yuvaltassa

STYLEGUIDE.md

@@ -6,7 +6,8 @@ possible in your code contributions.
 
 ### Scope of this guide
 
-Most of this guide involves C/C++ code. For Python, jump to the section [below](#python-code). For MuJoCo C/C++, code has three main categories:
+Most of this guide involves C/C++ code. For Python, jump to the section
+[below](#python-code). For MuJoCo C/C++, code has three main categories:
 
 1. **C code:** MuJoCo's core codebase. It consists of public headers under
 `include/` and C source files and internal headers under `src/`. This style
@@ -144,7 +145,7 @@ assignments:
   variable initialisation in `for` loops. For example, inspect the
   `mju_transpose` implementation above.
 
-- Three blank lines are required between function implementations in source files.
+- Two blank lines are required between function implementations in source files.
 
 #### Variable declarations
 
@@ -161,4 +162,7 @@ helping us to complete the migration are very welcome.
 
 ### [Python code](#python-code)
 
-For Python code, run `pyink foo.py` to adhere to Google's [Python style guide](https://google.github.io/styleguide/pyguide.html). For sorting and cleaning imports, run `isort foo.py`. Both `pyink` and `isort` can be pip installed via `pip install pyink isort`.
+For Python code, run `pyink foo.py` to adhere to Google's
+[Python style guide](https://google.github.io/styleguide/pyguide.html). For
+sorting and cleaning imports, run `isort foo.py`. Both `pyink` and `isort` can
+be pip installed via `pip install pyink isort`.

src/engine/engine_collision_box.c

@@ -91,7 +91,6 @@ int mjraw_SphereBox(mjContact* con, mjtNum margin,
 }
 
 
-
 // sphere : box
 int mjc_SphereBox(const mjModel* m, const mjData* d, mjContact* con,
                   int g1, int g2, mjtNum margin)
@@ -102,7 +101,6 @@ int mjc_SphereBox(const mjModel* m, const mjData* d, mjContact* con,
 }
 
 
-
 /* GENERAL THEORY OF OPERATION
    the following code is mostly for finding (line segment)/(box) collision
    after which box-sphere is called
@@ -601,7 +599,6 @@ int mjc_CapsuleBox(const mjModel* m, const mjData* d, mjContact* con,
 }
 
 
-
 // box : box
 int mjc_BoxBox(const mjModel* M, const mjData* D, mjContact* con, int g1, int g2, mjtNum margin)
 {

src/engine/engine_collision_convex.c

@@ -84,7 +84,6 @@ static int mjc_penetration(const mjModel* m, mjCCDObj* obj1, mjCCDObj* obj2,
 }
 
 
-
 // ccd center function
 void mjccd_center(const void *obj, ccd_vec3_t *center) {
   mjc_center(center->v, (const mjCCDObj*) obj);
@@ -114,7 +113,6 @@ void mjc_center(mjtNum res[3], const mjCCDObj *obj) {
 }
 
 
-
 // prism center function
 static void mjc_prism_center(mjtNum res[3], const mjCCDObj* obj) {
   // compute mean
@@ -126,7 +124,6 @@ static void mjc_prism_center(mjtNum res[3], const mjCCDObj* obj) {
 }
 
 
-
 // ccd prism center function
 static void mjccd_prism_center(const void *obj, ccd_vec3_t *center) {
   mjc_prism_center(center->v, (const mjCCDObj*) obj);
@@ -143,7 +140,6 @@ static inline void mulMatTVec3(mjtNum res[3], const mjtNum mat[9], const mjtNum
 }
 
 
-
 // transform a vector from local to global frame
 static inline void localToGlobal(mjtNum res[3], const mjtNum mat[9], const mjtNum dir[3],
                                  const mjtNum pos[3]) {
@@ -157,7 +153,6 @@ static inline void localToGlobal(mjtNum res[3], const mjtNum mat[9], const mjtNu
 }
 
 
-
 // point support function
 void mjc_pointSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3]) {
   const mjtNum* pos = obj->data->geom_xpos + 3*obj->geom;
@@ -167,7 +162,6 @@ void mjc_pointSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3]) {
 }
 
 
-
 // sphere support function
 static void mjc_sphereSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3]) {
   const mjModel* m = obj->model;
@@ -183,7 +177,6 @@ static void mjc_sphereSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3])
 }
 
 
-
 // line support function (capsule)
 void mjc_lineSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3]) {
   const mjModel* m = obj->model;
@@ -208,7 +201,6 @@ void mjc_lineSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3]) {
 }
 
 
-
 // capsule support function
 static void mjc_capsuleSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3]) {
   const mjModel* m = obj->model;
@@ -238,7 +230,6 @@ static void mjc_capsuleSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3]
 }
 
 
-
 // ellipsoid support function
 static void mjc_ellipsoidSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3]) {
   const mjModel* m = obj->model;
@@ -278,7 +269,6 @@ static void mjc_ellipsoidSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[
 }
 
 
-
 // cylinder support function
 static void mjc_cylinderSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3]) {
   const mjModel* m = obj->model;
@@ -311,7 +301,6 @@ static void mjc_cylinderSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3
 }
 
 
-
 // box support function
 static void mjc_boxSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3]) {
   const mjModel* m = obj->model;
@@ -343,14 +332,12 @@ static void mjc_boxSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3]) {
 }
 
 
-
 // dot product between mjtNum and float
 static inline mjtNum dot3f(const mjtNum a[3], const float b[3]) {
   return a[0]*(mjtNum)b[0] + a[1]*(mjtNum)b[1] + a[2]*(mjtNum)b[2];
 }
 
 
-
 // mesh support function via exhaustive search
 static void mjc_meshSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3]) {
   const mjModel* m = obj->model;
@@ -398,7 +385,6 @@ static void mjc_meshSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3]) {
 }
 
 
-
 // mesh support function via hill climbing
 static void mjc_hillclimbSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3]) {
   const mjModel* m = obj->model;
@@ -449,7 +435,6 @@ static void mjc_hillclimbSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[
 }
 
 
-
 // prism support function
 static void mjc_prism_support(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3]) {
   int istart, ibest;
@@ -471,7 +456,6 @@ static void mjc_prism_support(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3])
 }
 
 
-
 // flex support function
 static void mjc_flexSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3]) {
   const mjModel* m = obj->model;
@@ -512,7 +496,6 @@ static void mjc_flexSupport(mjtNum res[3], mjCCDObj* obj, const mjtNum dir[3]) {
 }
 
 
-
 // libccd support function
 void mjccd_support(const void *_obj, const ccd_vec3_t *_dir, ccd_vec3_t *vec) {
   mjCCDObj *obj = (mjCCDObj *)_obj;
@@ -720,7 +703,6 @@ void mjccd_support(const void *_obj, const ccd_vec3_t *_dir, ccd_vec3_t *vec) {
 }
 
 
-
 // libccd prism support function
 static void mjccd_prism_support(const void *obj, const ccd_vec3_t *dir, ccd_vec3_t *vec) {
   mjc_prism_support(vec->v, (mjCCDObj*) obj, dir->v);
@@ -784,7 +766,6 @@ void mjc_initCCDObj(mjCCDObj* obj, const mjModel* m, const mjData* d, int g, mjt
 }
 
 
-
 // set flex data for CCD object
 static void mjc_setCCDObjFlex(mjCCDObj* obj, int flex, int elem, int vert) {
   obj->flex = flex;
@@ -793,7 +774,6 @@ static void mjc_setCCDObjFlex(mjCCDObj* obj, int flex, int elem, int vert) {
 }
 
 
-
 // initialize CCD structure
 static void mjc_initCCD(ccd_t* ccd, const mjModel* m) {
   CCD_INIT(ccd);
@@ -803,7 +783,6 @@ static void mjc_initCCD(ccd_t* ccd, const mjModel* m) {
 }
 
 
-
 // find convex-convex collision
 static int mjc_CCDIteration(const mjModel* m, const mjData* d, mjCCDObj* obj1, mjCCDObj* obj2,
                             mjContact* con, int max_contacts, mjtNum margin) {
@@ -873,7 +852,6 @@ static int mjc_CCDIteration(const mjModel* m, const mjData* d, mjCCDObj* obj1, m
 }
 
 
-
 // compare new contact to previous contacts, return 1 if it is far from all of them
 static int mjc_isDistinctContact(mjContact* con, int ncon, mjtNum tolerance) {
   for (int i=0; i < ncon-1; i++) {
@@ -885,7 +863,6 @@ static int mjc_isDistinctContact(mjContact* con, int ncon, mjtNum tolerance) {
 }
 
 
-
 // in-place rotation of spatial frame around given point of origin
 static void mju_rotateFrame(const mjtNum origin[3], const mjtNum rot[9],
                             mjtNum xmat[9], mjtNum xpos[3]) {
@@ -907,7 +884,6 @@ static void mju_rotateFrame(const mjtNum origin[3], const mjtNum rot[9],
 }
 
 
-
 // return number of contacts supported by a single pass of narrowphase
 static int maxContacts(const mjCCDObj* obj1, const mjCCDObj* obj2) {
   const mjModel* m = obj1->model;
@@ -936,7 +912,6 @@ static int maxContacts(const mjCCDObj* obj1, const mjCCDObj* obj2) {
 }
 
 
-
 // multi-point convex-convex collision, using libccd
 int mjc_Convex(const mjModel* m, const mjData* d,
                mjContact* con, int g1, int g2, mjtNum margin) {
@@ -1024,7 +999,6 @@ int mjc_Convex(const mjModel* m, const mjData* d,
 }
 
 
-
 // parameters for plane-mesh extra contacts
 const int maxplanemesh = 3;
 const mjtNum tolplanemesh = 0.3;
@@ -1063,7 +1037,6 @@ static int addplanemesh(mjContact* con, const float vertex[3],
 }
 
 
-
 // plane-convex collision, using libccd
 int mjc_PlaneConvex(const mjModel* m, const mjData* d,
                     mjContact* con, int g1, int g2, mjtNum margin) {
@@ -1164,7 +1137,6 @@ int mjc_PlaneConvex(const mjModel* m, const mjData* d,
 }
 
 
-
 //----------------------------  heightfield collisions ---------------------------------------------
 
 // ccd prism first dir
@@ -1191,7 +1163,6 @@ static void addVert(int* nvert, mjCCDObj* obj, mjtNum x, mjtNum y, mjtNum z) {
 }
 
 
-
 // entry point for heightfield collisions
 int mjc_ConvexHField(const mjModel* m, const mjData* d,
                      mjContact* con, int g1, int g2, mjtNum margin) {
@@ -1379,7 +1350,6 @@ int mjc_ConvexHField(const mjModel* m, const mjData* d,
 }
 
 
-
 //--------------------------- fix contact frame normal ---------------------------------------------
 
 // compute normal for point outside ellipsoid, using ray-projection SQP
@@ -1437,7 +1407,6 @@ static int mjc_ellipsoidInside(mjtNum nrm[3], const mjtNum pos[3], const mjtNum
 }
 
 
-
 // compute normal for point inside ellipsoid, using diagonal QCQP
 static int mjc_ellipsoidOutside(mjtNum nrm[3], const mjtNum pos[3], const mjtNum size[3]) {
   // algorithm constants
@@ -1487,7 +1456,6 @@ static int mjc_ellipsoidOutside(mjtNum nrm[3], const mjtNum pos[3], const mjtNum
 }
 
 
-
 // entry point
 void mjc_fixNormal(const mjModel* m, const mjData* d, mjContact* con, int g1, int g2) {
   mjtNum dst1, dst2;
@@ -1637,7 +1605,6 @@ void mjc_fixNormal(const mjModel* m, const mjData* d, mjContact* con, int g1, in
 }
 
 
-
 //----------------------------  flex collisions ---------------------------------------------
 
 // geom-elem or elem-elem or vert-elem convex collision using ccd
@@ -1654,7 +1621,6 @@ int mjc_ConvexElem(const mjModel* m, const mjData* d, mjContact* con,
 }
 
 
-
 // test a height field and a flex element for collision
 int mjc_HFieldElem(const mjModel* m, const mjData* d, mjContact* con,
                    int g, int f, int e, mjtNum margin) {