gitea/SDL3_fork
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Added support for simulated vsync in the renderer

Browse Source 
This kicks in if the platform doesn't support vsync directly, or if the present fails for some reason (e.g. minimized on some platforms)

Fixes https://github.com/libsdl-org/SDL/issues/5134
This commit is contained in:
Sam Lantinga
2022-09-15 01:00:12 -07:00
parent 339f7a2f6b
commit d744aafb05
15 changed files with 115 additions and 37 deletions
Download Patch File Download Diff File Expand all files Collapse all files

61
src/render/SDL_render.c
View File

@@ -24,6 +24,7 @@
#include "SDL_hints.h"
#include "SDL_render.h"
#include "SDL_timer.h"
#include "SDL_sysrender.h"
#include "software/SDL_render_sw_c.h"
#include "../video/SDL_pixels_c.h"
@@ -1013,6 +1014,14 @@ SDL_CreateRenderer(SDL_Window * window, int index, Uint32 flags)
}
}
if ((flags & SDL_RENDERER_PRESENTVSYNC) != 0) {
renderer->wanted_vsync = SDL_TRUE;
if ((renderer->info.flags & SDL_RENDERER_PRESENTVSYNC) == 0) {
renderer->simulate_vsync = SDL_TRUE;
renderer->info.flags |= SDL_RENDERER_PRESENTVSYNC;
}
}
VerifyDrawQueueFunctions(renderer);
@@ -4260,9 +4269,38 @@ SDL_RenderReadPixels(SDL_Renderer * renderer, const SDL_Rect * rect,
format, pixels, pitch);
}
static void
SDL_RenderSimulateVSync(SDL_Renderer * renderer)
{
Uint32 now, elapsed;
const Uint32 interval = (1000 / 60); /* FIXME: What FPS? */
if (!interval) {
/* We can't do sub-ms delay, so just return here */
return;
}
now = SDL_GetTicks();
elapsed = (now - renderer->last_present);
if (elapsed < interval) {
Uint32 duration = (interval - elapsed);
SDL_Delay(duration);
now = SDL_GetTicks();
}
if (renderer->last_present) {
elapsed = (now - renderer->last_present);
renderer->last_present += (elapsed / interval) * interval;
} else {
renderer->last_present = now;
}
}
void
SDL_RenderPresent(SDL_Renderer * renderer)
{
SDL_bool presented = SDL_TRUE;
CHECK_RENDERER_MAGIC(renderer, );
FlushRenderCommands(renderer); /* time to send everything to the GPU! */
@@ -4270,11 +4308,17 @@ SDL_RenderPresent(SDL_Renderer * renderer)
#if DONT_DRAW_WHILE_HIDDEN
/* Don't present while we're hidden */
if (renderer->hidden) {
return;
}
presented = SDL_FALSE;
} else
#endif
if (renderer->RenderPresent(renderer) < 0) {
presented = SDL_FALSE;
}
renderer->RenderPresent(renderer);
if (renderer->simulate_vsync ||
(!presented && renderer->wanted_vsync)) {
SDL_RenderSimulateVSync(renderer);
}
}
void
@@ -4530,10 +4574,15 @@ SDL_RenderSetVSync(SDL_Renderer * renderer, int vsync)
return SDL_Unsupported();
}
if (renderer->SetVSync) {
return renderer->SetVSync(renderer, vsync);
renderer->wanted_vsync = vsync ? SDL_TRUE : SDL_FALSE;
if (!renderer->SetVSync ||
renderer->SetVSync(renderer, vsync) < 0) {
renderer->simulate_vsync = vsync ? SDL_TRUE : SDL_FALSE;
} else {
renderer->simulate_vsync = SDL_FALSE;
}
return SDL_Unsupported();
return 0;
}
/* vi: set ts=4 sw=4 expandtab: */