pj_fwd()/pj_inv(): performance improvements through passing by ref and less function calls

2 files changed, 60 insertions, 58 deletions

diff --git a/src/fwd.cpp b/src/fwd.cpp
index 97ba5999..8583a6e7 100644
--- a/src/fwd.cpp
+++ b/src/fwd.cpp
@@ -38,9 +38,12 @@
 #define OUTPUT_UNITS P->right
 
 
-static PJ_COORD fwd_prepare (PJ *P, PJ_COORD coo) {
+static void fwd_prepare (PJ *P, PJ_COORD& coo) {
     if (HUGE_VAL==coo.v[0] || HUGE_VAL==coo.v[1] || HUGE_VAL==coo.v[2])
-        return proj_coord_error ();
+    {
+        coo = proj_coord_error ();
+        return;
+    }
 
     /* The helmert datum shift will choke unless it gets a sensible 4D coordinate */
     if (HUGE_VAL==coo.v[2] && P->helmert) coo.v[2] = 0.0;
@@ -56,13 +59,15 @@ static PJ_COORD fwd_prepare (PJ *P, PJ_COORD coo) {
         {
             proj_log_error(P, _("Invalid latitude"));
             proj_errno_set (P, PROJ_ERR_COORD_TRANSFM_INVALID_COORD);
-            return proj_coord_error ();
+            coo = proj_coord_error ();
+            return;
         }
         if (coo.lp.lam > 10  ||  coo.lp.lam < -10)
         {
             proj_log_error(P, _("Invalid longitude"));
             proj_errno_set (P, PROJ_ERR_COORD_TRANSFM_INVALID_COORD);
-            return proj_coord_error ();
+            coo = proj_coord_error ();
+            return;
         }
 
 
@@ -89,7 +94,7 @@ static PJ_COORD fwd_prepare (PJ *P, PJ_COORD coo) {
             coo = proj_trans (P->cart,       PJ_INV, coo); /* Go back to angular using local ellps */
         }
         if (coo.lp.lam==HUGE_VAL)
-            return coo;
+            return;
         if (P->vgridshift)
             coo = proj_trans (P->vgridshift, PJ_FWD, coo); /* Go orthometric from geometric */
 
@@ -100,18 +105,18 @@ static PJ_COORD fwd_prepare (PJ *P, PJ_COORD coo) {
         if (0==P->over)
             coo.lp.lam = adjlon(coo.lp.lam);
 
-        return coo;
+        return;
     }
 
 
     /* We do not support gridshifts on cartesian input */
     if (INPUT_UNITS==PJ_IO_UNITS_CARTESIAN && P->helmert)
-            return proj_trans (P->helmert, PJ_INV, coo);
-    return coo;
+            coo = proj_trans (P->helmert, PJ_INV, coo);
+    return;
 }
 
 
-static PJ_COORD fwd_finalize (PJ *P, PJ_COORD coo) {
+static void fwd_finalize (PJ *P, PJ_COORD& coo) {
 
     switch (OUTPUT_UNITS) {
 
@@ -161,29 +166,28 @@ static PJ_COORD fwd_finalize (PJ *P, PJ_COORD coo) {
 
     if (P->axisswap)
         coo = proj_trans (P->axisswap, PJ_FWD, coo);
-
-    return coo;
 }
 
 
-static PJ_COORD error_or_coord(PJ *P, PJ_COORD coord, int last_errno) {
-    if (proj_errno(P))
+static inline PJ_COORD error_or_coord(PJ *P, PJ_COORD coord, int last_errno) {
+    if (P->ctx->last_errno)
         return proj_coord_error();
 
-    proj_errno_restore(P, last_errno);
+    P->ctx->last_errno = last_errno;
+
     return coord;
 }
 
 
 PJ_XY pj_fwd(PJ_LP lp, PJ *P) {
-    int last_errno;
     PJ_COORD coo = {{0,0,0,0}};
     coo.lp = lp;
 
-    last_errno = proj_errno_reset(P);
+    const int last_errno = P->ctx->last_errno;
+    P->ctx->last_errno = 0;
 
     if (!P->skip_fwd_prepare)
-        coo = fwd_prepare (P, coo);
+        fwd_prepare (P, coo);
     if (HUGE_VAL==coo.v[0] || HUGE_VAL==coo.v[1])
         return proj_coord_error ().xy;
 
@@ -202,7 +206,7 @@ PJ_XY pj_fwd(PJ_LP lp, PJ *P) {
         return proj_coord_error ().xy;
 
     if (!P->skip_fwd_finalize)
-        coo = fwd_finalize (P, coo);
+        fwd_finalize (P, coo);
 
     return error_or_coord(P, coo, last_errno).xy;
 }
@@ -210,14 +214,14 @@ PJ_XY pj_fwd(PJ_LP lp, PJ *P) {
 
 
 PJ_XYZ pj_fwd3d(PJ_LPZ lpz, PJ *P) {
-    int last_errno;
     PJ_COORD coo = {{0,0,0,0}};
     coo.lpz = lpz;
 
-    last_errno = proj_errno_reset(P);
+    const int last_errno = P->ctx->last_errno;
+    P->ctx->last_errno = 0;
 
     if (!P->skip_fwd_prepare)
-        coo = fwd_prepare (P, coo);
+        fwd_prepare (P, coo);
     if (HUGE_VAL==coo.v[0])
         return proj_coord_error ().xyz;
 
@@ -236,7 +240,7 @@ PJ_XYZ pj_fwd3d(PJ_LPZ lpz, PJ *P) {
         return proj_coord_error ().xyz;
 
     if (!P->skip_fwd_finalize)
-        coo = fwd_finalize (P, coo);
+        fwd_finalize (P, coo);
 
     return error_or_coord(P, coo, last_errno).xyz;
 }
@@ -244,10 +248,12 @@ PJ_XYZ pj_fwd3d(PJ_LPZ lpz, PJ *P) {
 
 
 PJ_COORD pj_fwd4d (PJ_COORD coo, PJ *P) {
-    int last_errno = proj_errno_reset(P);
+
+    const int last_errno = P->ctx->last_errno;
+    P->ctx->last_errno = 0;
 
     if (!P->skip_fwd_prepare)
-        coo = fwd_prepare (P, coo);
+        fwd_prepare (P, coo);
     if (HUGE_VAL==coo.v[0])
         return proj_coord_error ();
 
@@ -266,7 +272,7 @@ PJ_COORD pj_fwd4d (PJ_COORD coo, PJ *P) {
         return proj_coord_error ();
 
     if (!P->skip_fwd_finalize)
-        coo = fwd_finalize (P, coo);
+        fwd_finalize (P, coo);
 
     return error_or_coord(P, coo, last_errno);
 }
diff --git a/src/inv.cpp b/src/inv.cpp
index b4a42189..8925f0e9 100644
--- a/src/inv.cpp
+++ b/src/inv.cpp
@@ -36,10 +36,11 @@
 #define INPUT_UNITS  P->right
 #define OUTPUT_UNITS P->left
 
-static PJ_COORD inv_prepare (PJ *P, PJ_COORD coo) {
+static void inv_prepare (PJ *P, PJ_COORD& coo) {
     if (coo.v[0] == HUGE_VAL || coo.v[1] == HUGE_VAL || coo.v[2] == HUGE_VAL) {
         proj_errno_set (P, PROJ_ERR_COORD_TRANSFM_OUTSIDE_PROJECTION_DOMAIN);
-        return proj_coord_error ();
+        coo = proj_coord_error ();
+        return;
     }
 
     /* The helmert datum shift will choke unless it gets a sensible 4D coordinate */
@@ -52,10 +53,10 @@ static PJ_COORD inv_prepare (PJ *P, PJ_COORD coo) {
     /* Handle remaining possible input types */
     switch (INPUT_UNITS) {
     case PJ_IO_UNITS_WHATEVER:
-        return coo;
+        break;
 
     case PJ_IO_UNITS_DEGREES:
-        return coo;
+        break;
 
     /* de-scale and de-offset */
     case PJ_IO_UNITS_CARTESIAN:
@@ -65,8 +66,7 @@ static PJ_COORD inv_prepare (PJ *P, PJ_COORD coo) {
         if (P->is_geocent) {
             coo = proj_trans (P->cart, PJ_INV, coo);
         }
-
-        return coo;
+        break;
 
     case PJ_IO_UNITS_PROJECTED:
     case PJ_IO_UNITS_CLASSIC:
@@ -74,7 +74,7 @@ static PJ_COORD inv_prepare (PJ *P, PJ_COORD coo) {
         coo.xyz.y = P->to_meter  * coo.xyz.y - P->y0;
         coo.xyz.z = P->vto_meter * coo.xyz.z - P->z0;
         if (INPUT_UNITS==PJ_IO_UNITS_PROJECTED)
-            return coo;
+            return;
 
         /* Classic proj.4 functions expect plane coordinates in units of the semimajor axis  */
         /* Multiplying by ra, rather than dividing by a because the CalCOFI projection       */
@@ -82,23 +82,20 @@ static PJ_COORD inv_prepare (PJ *P, PJ_COORD coo) {
         /* (CalCOFI avoids further scaling by stomping - but a better solution is possible)  */
         coo.xyz.x *= P->ra;
         coo.xyz.y *= P->ra;
-        return coo;
+        break;
 
     case PJ_IO_UNITS_RADIANS:
         coo.lpz.z = P->vto_meter * coo.lpz.z - P->z0;
         break;
     }
-
-    /* Should not happen, so we could return pj_coord_err here */
-    return coo;
 }
 
 
 
-static PJ_COORD inv_finalize (PJ *P, PJ_COORD coo) {
+static void inv_finalize (PJ *P, PJ_COORD& coo) {
     if (coo.xyz.x == HUGE_VAL) {
         proj_errno_set (P, PROJ_ERR_COORD_TRANSFM_OUTSIDE_PROJECTION_DOMAIN);
-        return proj_coord_error ();
+        coo = proj_coord_error ();
     }
 
     if (OUTPUT_UNITS==PJ_IO_UNITS_RADIANS) {
@@ -113,7 +110,7 @@ static PJ_COORD inv_finalize (PJ *P, PJ_COORD coo) {
         if (P->vgridshift)
             coo = proj_trans (P->vgridshift, PJ_INV, coo); /* Go geometric from orthometric */
         if (coo.lp.lam==HUGE_VAL)
-            return coo;
+            return;
         if (P->hgridshift)
             coo = proj_trans (P->hgridshift, PJ_FWD, coo);
         else if (P->helmert || (P->cart_wgs84 != nullptr && P->cart != nullptr)) {
@@ -123,35 +120,32 @@ static PJ_COORD inv_finalize (PJ *P, PJ_COORD coo) {
             coo = proj_trans (P->cart_wgs84, PJ_INV, coo); /* Go back to angular using WGS84 ellps */
         }
         if (coo.lp.lam==HUGE_VAL)
-            return coo;
+            return;
 
         /* If input latitude was geocentrical, convert back to geocentrical */
         if (P->geoc)
             coo = pj_geocentric_latitude (P, PJ_FWD, coo);
     }
-
-    return coo;
 }
 
-
-static PJ_COORD error_or_coord(PJ *P, PJ_COORD coord, int last_errno) {
-    if (proj_errno(P))
+static inline PJ_COORD error_or_coord(PJ *P, PJ_COORD coord, int last_errno) {
+    if (P->ctx->last_errno)
         return proj_coord_error();
 
-    proj_errno_restore(P, last_errno);
+    P->ctx->last_errno = last_errno;
+
     return coord;
 }
 
-
 PJ_LP pj_inv(PJ_XY xy, PJ *P) {
-    int last_errno;
     PJ_COORD coo = {{0,0,0,0}};
     coo.xy = xy;
 
-    last_errno = proj_errno_reset(P);
+    const int last_errno = P->ctx->last_errno;
+    P->ctx->last_errno = 0;
 
     if (!P->skip_inv_prepare)
-        coo = inv_prepare (P, coo);
+        inv_prepare (P, coo);
     if (HUGE_VAL==coo.v[0])
         return proj_coord_error ().lp;
 
@@ -170,7 +164,7 @@ PJ_LP pj_inv(PJ_XY xy, PJ *P) {
         return proj_coord_error ().lp;
 
     if (!P->skip_inv_finalize)
-        coo = inv_finalize (P, coo);
+        inv_finalize (P, coo);
 
     return error_or_coord(P, coo, last_errno).lp;
 }
@@ -178,14 +172,14 @@ PJ_LP pj_inv(PJ_XY xy, PJ *P) {
 
 
 PJ_LPZ pj_inv3d (PJ_XYZ xyz, PJ *P) {
-    int last_errno;
     PJ_COORD coo = {{0,0,0,0}};
     coo.xyz = xyz;
 
-    last_errno = proj_errno_reset(P);
+    const int last_errno = P->ctx->last_errno;
+    P->ctx->last_errno = 0;
 
     if (!P->skip_inv_prepare)
-        coo = inv_prepare (P, coo);
+         inv_prepare (P, coo);
     if (HUGE_VAL==coo.v[0])
         return proj_coord_error ().lpz;
 
@@ -204,7 +198,7 @@ PJ_LPZ pj_inv3d (PJ_XYZ xyz, PJ *P) {
         return proj_coord_error ().lpz;
 
     if (!P->skip_inv_finalize)
-        coo = inv_finalize (P, coo);
+        inv_finalize (P, coo);
 
     return error_or_coord(P, coo, last_errno).lpz;
 }
@@ -212,10 +206,12 @@ PJ_LPZ pj_inv3d (PJ_XYZ xyz, PJ *P) {
 
 
 PJ_COORD pj_inv4d (PJ_COORD coo, PJ *P) {
-    int last_errno = proj_errno_reset(P);
+
+    const int last_errno = P->ctx->last_errno;
+    P->ctx->last_errno = 0;
 
     if (!P->skip_inv_prepare)
-        coo = inv_prepare (P, coo);
+        inv_prepare (P, coo);
     if (HUGE_VAL==coo.v[0])
         return proj_coord_error ();
 
@@ -234,7 +230,7 @@ PJ_COORD pj_inv4d (PJ_COORD coo, PJ *P) {
         return proj_coord_error ();
 
     if (!P->skip_inv_finalize)
-        coo = inv_finalize (P, coo);
+        inv_finalize (P, coo);
 
     return error_or_coord(P, coo, last_errno);
 }