[client] reworked the polling logic yet again

This commit is contained in:
Geoffrey McRae 2017-12-07 16:07:25 +11:00
parent eb52ee9412
commit 032602f336

View File

@ -16,6 +16,9 @@ this program; if not, write to the Free Software Foundation, Inc., 59 Temple
Place, Suite 330, Boston, MA 02111-1307 USA
*/
// limit the FPS when sync is turned off
#define FPS_LIMIT 240
#include <getopt.h>
#include <SDL2/SDL.h>
#include <SDL_ttf.h>
@ -185,75 +188,63 @@ int renderThread(void * unused)
SDL_Texture * textTexture = NULL;
SDL_Rect textRect;
const uint64_t presentTime = detectPresentTime();
const uint64_t presentTime =
params.vsync ?
detectPresentTime() :
ceil((1000000.0/(double)FPS_LIMIT));
uint64_t pollDelay = 0;
unsigned int lateCount = 0;
int pollDelay = 0;
uint64_t drawStart = 0;
uint64_t drawTime = 0;
int drawTime = 0;
uint64_t fpsStart = 0;
uint64_t fpsTime = 0;
uint64_t fpsStart = microtime();
int fpsTime = 0;
unsigned int retardCount = 0;
unsigned int resyncCount = 0;
#define SYNC_WINDOW 2000
volatile uint64_t * dataPos = &state.shm->dataPos;
while(state.running)
{
// wait for a frame
if (pollDelay > SYNC_WINDOW)
usleep(pollDelay - SYNC_WINDOW);
else
usleep(pollDelay);
// we shouldn't have a frame yet, retard the timing a bit
if (header.dataPos != state.shm->dataPos)
// if the next frame isn't aready available
if (header.dataPos == *dataPos)
{
++retardCount;
if (pollDelay >= SYNC_WINDOW / 2)
pollDelay -= SYNC_WINDOW / 2;
else
pollDelay = 0;
}
else
{
const uint64_t loopStart = microtime();
while(header.dataPos == state.shm->dataPos && state.running)
{
// if we timed out, wait for an interrupt or a timeout
if (microtime() - loopStart > SYNC_WINDOW)
{
if (ivshmem_wait_irq(0, 1000000/30) == IVSHMEM_WAIT_RESULT_OK)
{
// might be a spurious interrupt we didn't answer earlier
if (header.dataPos == state.shm->dataPos)
continue;
// wait for a frame
const uint64_t pollStart = microtime();
if (pollDelay > 0)
usleep(pollDelay);
++resyncCount;
}
if (header.dataPos != *dataPos)
++lateCount;
// poll until we have a new frame, or we time out
while(header.dataPos == *dataPos && state.running) {
if (microtime() - pollStart > 100)
break;
}
}
pollDelay += microtime() - loopStart;
pollDelay -= SYNC_WINDOW / 2;
if (pollDelay > (1000000/30))
pollDelay = presentTime;
// update the delay
pollDelay = microtime() - pollStart - 100;
}
if (!state.running)
break;
// sleep for the remainder of the presentation time
if (frameCount > 0)
{
drawTime = microtime() - drawStart;
const uint64_t t = microtime();
drawTime = t - drawStart;
if (drawTime < presentTime)
{
uint64_t delta = presentTime - drawTime;
const uint64_t delta = presentTime - drawTime;
if (delta > 1000)
usleep(delta - 1000);
if (!params.vsync)
{
// poll for the final microsecond
const uint64_t target = t + delta;
while(microtime() <= target) {}
}
}
// ensure buffers are flushed
@ -401,7 +392,7 @@ int renderThread(void * unused)
char str[128];
const float avgFPS = 1000.0f / (((float)fpsTime / frameCount) / 1000.0f);
snprintf(str, sizeof(str), "FPS: %8.4f, Retard: %d, Resync: %d", avgFPS, retardCount, resyncCount);
snprintf(str, sizeof(str), "FPS: %8.4f (Frames: %d, Late: %d)", avgFPS, frameCount, lateCount);
SDL_Color color = {0xff, 0xff, 0xff};
if (!(textSurface = TTF_RenderText_Blended(state.font, str, color)))
{
@ -420,6 +411,7 @@ int renderThread(void * unused)
fpsTime = 0;
frameCount = 0;
lateCount = 0;
}
if (textTexture)