Updated random interface so we can optionally specify our own seed value.

simgear/math/sg_random.c

@@ -49,9 +49,7 @@
 
 // Seed the random number generater with time() so we don't see the
 // same sequence every time
-void sg_srandom(void) {
-    // fgPrintf( FG_MATH, FG_INFO, "Seeding random number generater\n");
-
+void sg_srandom_time(void) {
 #ifdef HAVE_RAND
     srand(time(NULL));
 #else
@@ -60,6 +58,17 @@ void sg_srandom(void) {
 }
 
 
+// Seed the random number generater with your own seed so can set up
+// repeatable randomization.
+void sg_srandom( unsigned int seed ) {
+#ifdef HAVE_RAND
+    srand( seed );
+#else
+    srandom( seed );
+#endif                                       
+}
+
+
 // return a random number between [0.0, 1.0)
 double sg_random(void) {
 #ifdef HAVE_RAND

simgear/math/sg_random.h

@@ -33,7 +33,11 @@ extern "C" {
 
 // Seed the random number generater with time() so we don't see the
 // same sequence every time
-void sg_srandom(void);
+void sg_srandom_time(void);
+
+// Seed the random number generater with your own seed so can set up
+// repeatable randomization.
+void sg_srandom( unsigned int seed );
 
 // return a random number between [0.0, 1.0)
 double sg_random(void);