Fixed bug 5404 - stdlib: Added SDL_round, SDL_roundf, SDL_lround and SDL_lroundf

Cameron Cawley

stdlib: Added SDL_round, SDL_roundf, SDL_lround and SDL_lroundf

The default implementation is based on the one used in the Windows RT video driver.

src/dynapi/SDL_dynapi_overrides.h

@@ -788,4 +788,8 @@
 #define SDL_GameControllerGetSensorData SDL_GameControllerGetSensorData_REAL
 #define SDL_wcscasecmp SDL_wcscasecmp_REAL
 #define SDL_wcsncasecmp SDL_wcsncasecmp_REAL
+#define SDL_round SDL_round_REAL
+#define SDL_roundf SDL_roundf_REAL
+#define SDL_lround SDL_lround_REAL
+#define SDL_lroundf SDL_lroundf_REAL
 #define SDL_SoftStretchLinear SDL_SoftStretchLinear_REAL

src/dynapi/SDL_dynapi_procs.h

@@ -849,4 +849,8 @@ SDL_DYNAPI_PROC(SDL_bool,SDL_GameControllerIsSensorEnabled,(SDL_GameController *
 SDL_DYNAPI_PROC(int,SDL_GameControllerGetSensorData,(SDL_GameController *a, SDL_SensorType b, float *c, int d),(a,b,c,d),return)
 SDL_DYNAPI_PROC(int,SDL_wcscasecmp,(const wchar_t *a, const wchar_t *b),(a,b),return)
 SDL_DYNAPI_PROC(int,SDL_wcsncasecmp,(const wchar_t *a, const wchar_t *b, size_t c),(a,b,c),return)
+SDL_DYNAPI_PROC(double,SDL_round,(double a),(a),return)
+SDL_DYNAPI_PROC(float,SDL_roundf,(float a),(a),return)
+SDL_DYNAPI_PROC(long,SDL_lround,(double a),(a),return)
+SDL_DYNAPI_PROC(long,SDL_lroundf,(float a),(a),return)
 SDL_DYNAPI_PROC(int,SDL_SoftStretchLinear,(SDL_Surface *a, const SDL_Rect *b, SDL_Surface *c, const SDL_Rect *d),(a,b,c,d),return)

src/stdlib/SDL_stdlib.c

@@ -364,6 +364,50 @@ SDL_powf(float x, float y)
 #endif
 }
 
+double
+SDL_round(double arg)
+{
+#if defined HAVE_ROUND
+    return round(arg);
+#else
+    if (arg >= 0.0) {
+        return SDL_floor(arg + 0.5);
+    } else {
+        return SDL_ceil(arg - 0.5);
+    }
+#endif
+}
+
+float
+SDL_roundf(float arg)
+{
+#if defined HAVE_ROUNDF
+    return roundf(arg);
+#else
+    return (float)SDL_round((double)arg);
+#endif
+}
+
+long
+SDL_lround(double arg)
+{
+#if defined HAVE_LROUND
+    return lround(arg);
+#else
+    return (long)SDL_round(arg);
+#endif
+}
+
+long
+SDL_lroundf(float arg)
+{
+#if defined HAVE_LROUNDF
+    return lroundf(arg);
+#else
+    return (long)SDL_round((double)arg);
+#endif
+}
+
 double
 SDL_scalbn(double x, int n)
 {

src/video/winrt/SDL_winrtpointerinput.cpp

@@ -116,16 +116,6 @@ WINRT_TransformCursorPosition(SDL_Window * window,
     return outputPosition;
 }
 
-static inline int
-_lround(float arg)
-{
-    if (arg >= 0.0f) {
-        return (int)floor(arg + 0.5f);
-    } else {
-        return (int)ceil(arg - 0.5f);
-    }
-}
-
 Uint8
 WINRT_GetSDLButtonForPointerPoint(Windows::UI::Input::PointerPoint ^pt)
 {
@@ -389,8 +379,8 @@ WINRT_ProcessMouseMovedEvent(SDL_Window * window, Windows::Devices::Input::Mouse
         window,
         0,
         1,
-        _lround(mouseDeltaInSDLWindowCoords.X),
-        _lround(mouseDeltaInSDLWindowCoords.Y));
+        SDL_lroundf(mouseDeltaInSDLWindowCoords.X),
+        SDL_lroundf(mouseDeltaInSDLWindowCoords.Y));
 }
 
 #endif // SDL_VIDEO_DRIVER_WINRT

src/video/x11/SDL_x11modes.c

@@ -257,7 +257,7 @@ static int
 CalculateXRandRRefreshRate(const XRRModeInfo *info)
 {
     return (info->hTotal && info->vTotal) ?
-        round(((double)info->dotClock / (double)(info->hTotal * info->vTotal))) : 0;
+        SDL_round(((double)info->dotClock / (double)(info->hTotal * info->vTotal))) : 0;
 }
 
 static SDL_bool