Deduct frame execution time from sleep time

Fixes failure to sustain cl_maxfps/sys_ticrate when the system can
exceed it if unlimited, should improve frame pacing too.

Includes related refactoring. Actually this commit is mostly refactoring.

Signed-off-by: bones_was_here <bones_was_here@xonotic.au>

diff --git a/host.c b/host.c
index d2725cc2f85c07dc3eb7693f87de22149e8fd04f..0957102430ff74c1a078b87acd3096b256698222 100644 (file)
--- a/host.c
+++ b/host.c
@@ -648,35 +648,34 @@ static double Host_Frame(double time)
 
        R_TimeReport("---");
 
-       sv_wait = SV_Frame(time);
-       cl_wait = CL_Frame(time);
-
-//     Con_Printf("%6.0f %6.0f\n", cl_wait * 1000000.0, sv_wait * 1000000.0);
+       // if the accumulators haven't become positive yet, wait a while
+       sv_wait = - SV_Frame(time);
+       cl_wait = - CL_Frame(time);
 
        Mem_CheckSentinelsGlobal();
 
-       if(host.restless)
-               return 0;
-
-       // if the accumulators haven't become positive yet, wait a while
        if (cls.state == ca_dedicated)
-               return sv_wait * -1000000.0; // dedicated
+               return sv_wait; // dedicated
        else if (!sv.active || svs.threaded)
-               return cl_wait * -1000000.0; // connected to server, main menu, or server is on different thread
+               return cl_wait; // connected to server, main menu, or server is on different thread
        else
-               return max(cl_wait, sv_wait) * -1000000.0; // listen server or singleplayer
+               return min(cl_wait, sv_wait); // listen server or singleplayer
 }
 
-static inline void Host_Sleep(double time)
+static inline double Host_Sleep(double time)
 {
        double delta, time0;
 
+       // convert to microseconds
+       time *= 1000000.0;
+
+       if (time < 1 || host.restless)
+               return 0; // not sleeping this frame
+
        if(host_maxwait.value <= 0)
                time = min(time, 1000000.0);
        else
                time = min(time, host_maxwait.value * 1000.0);
-       if(time < 1)
-               time = 1; // because we cast to int
 
        time0 = Sys_DirtyTime();
        if (sv_checkforpacketsduringsleep.integer && !sys_usenoclockbutbenchmark.integer && !svs.threaded) {
@@ -691,12 +690,13 @@ static inline void Host_Sleep(double time)
                        Curl_Select(&time);
                Sys_Sleep((int)time);
        }
+
        delta = Sys_DirtyTime() - time0;
        if (delta < 0 || delta >= 1800)
                delta = 0;
-       host.sleeptime = delta;
-//                     R_TimeReport("sleep");
-       return;
+
+//     R_TimeReport("sleep");
+       return delta;
 }
 
 // Cloudwalk: Most overpowered function declaration...
@@ -722,7 +722,7 @@ static inline double Host_UpdateTime (double newtime, double oldtime)
 
 void Host_Main(void)
 {
-       double time, newtime, oldtime, sleeptime;
+       double time, oldtime, sleeptime;
 
        Host_Init(); // Start!
 
@@ -739,17 +739,15 @@ void Host_Main(void)
                        continue;
                }
 
-               newtime = host.dirtytime = Sys_DirtyTime();
-               host.realtime += time = Host_UpdateTime(newtime, oldtime);
+               host.dirtytime = Sys_DirtyTime();
+               host.realtime += time = Host_UpdateTime(host.dirtytime, oldtime);
 
                sleeptime = Host_Frame(time);
-               oldtime = newtime;
+               oldtime = host.dirtytime;
                ++host.framecount;
 
-               if (sleeptime >= 1)
-                       Host_Sleep(sleeptime);
-               else
-                       host.sleeptime = 0;
+               sleeptime -= Sys_DirtyTime() - host.dirtytime; // execution time
+               host.sleeptime = Host_Sleep(sleeptime);
        }
 
        return;