macOS display link improvements

parsec-cloud · Dec 26, 2023 · 09ccf9d · 09ccf9d
1 parent 4658aca
commit 09ccf9d
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Showing 4 changed files with 81 additions and 3 deletions.
diff --git a/src/unix/apple/macosx/gfx/display-link.h b/src/unix/apple/macosx/gfx/display-link.h
@@ -0,0 +1,52 @@
+// This Source Code Form is subject to the terms of the MIT License.
+// If a copy of the MIT License was not distributed with this file,
+// You can obtain one at https://spdx.org/licenses/MIT.html.
+
+struct display_link {
+	CVDisplayLinkRef link;
+	dispatch_semaphore_t semaphore;
+	MTY_Atomic64 counter;
+};
+
+static CVReturn display_link_output(CVDisplayLinkRef displayLink, const CVTimeStamp *inNow,
+	const CVTimeStamp *inOutputTime, CVOptionFlags flagsIn, CVOptionFlags *flagsOut,
+	void *displayLinkContext)
+{
+	struct display_link *ctx = displayLinkContext;
+
+	dispatch_semaphore_signal(ctx->semaphore);
+
+	MTY_Atomic64Add(&ctx->counter, 1);
+
+	return 0;
+}
+
+static void display_link_destroy(struct display_link *ctx)
+{
+	if (ctx->link) {
+		CVDisplayLinkStop(ctx->link);
+		CVDisplayLinkRelease(ctx->link);
+		ctx->link = NULL;
+	}
+
+	ctx->semaphore = nil;
+}
+
+static int64_t display_link_get_counter(struct display_link *ctx)
+{
+	return MTY_Atomic64Get(&ctx->counter);
+}
+
+static void display_link_delay(struct display_link *ctx, uint32_t interval)
+{
+	for (uint32_t x = 0; x < interval; x++) {
+		if (!ctx->link) {
+			ctx->semaphore = dispatch_semaphore_create(0);
+			CVDisplayLinkCreateWithCGDisplay(CGMainDisplayID(), &ctx->link);
+			CVDisplayLinkSetOutputCallback(ctx->link, display_link_output, ctx);
+			CVDisplayLinkStart(ctx->link);
+		}
+
+		dispatch_semaphore_wait(ctx->semaphore, DISPATCH_TIME_FOREVER);
+	}
+}
diff --git a/src/unix/apple/macosx/gfx/metal-ctx.m b/src/unix/apple/macosx/gfx/metal-ctx.m
@@ -9,6 +9,8 @@
 #include <AppKit/AppKit.h>
 #include <QuartzCore/CAMetalLayer.h>
 
+#include "gfx/sync.h"
+#include "display-link.h"
 #include "scale.h"
 
 struct metal_ctx {
@@ -17,6 +19,9 @@
 	id<CAMetalDrawable> back_buffer;
 	id<MTLCommandQueue> cq;
 	CGSize size;
+
+	struct sync sync;
+	struct display_link dlink;
 };
 
 static void metal_ctx_mt_block(void (^block)(void))
@@ -43,7 +48,14 @@ static void metal_ctx_mt_block(void (^block)(void))
 		ctx->layer = [CAMetalLayer layer];
 		ctx->layer.device = device;
 		ctx->layer.pixelFormat = MTLPixelFormatBGRA8Unorm;
-		ctx->layer.displaySyncEnabled = vsync ? YES : NO;
+
+		if (vsync) {
+			sync_set_interval(&ctx->sync, 100);
+			ctx->layer.displaySyncEnabled = YES;
+
+		} else {
+			ctx->layer.displaySyncEnabled = NO;
+		}
 
 		ctx->cq = [ctx->layer.device newCommandQueue];
 
@@ -61,6 +73,8 @@ void mty_metal_ctx_destroy(struct gfx_ctx **gfx_ctx)
 
 	struct metal_ctx *ctx = (struct metal_ctx *) *gfx_ctx;
 
+	display_link_destroy(&ctx->dlink);
+
 	ctx->window = nil;
 	ctx->layer = nil;
 	ctx->cq = nil;
@@ -122,18 +136,30 @@ static void metal_ctx_refresh(struct metal_ctx *ctx)
 
 void mty_metal_ctx_set_sync_interval(struct gfx_ctx *gfx_ctx, uint32_t interval)
 {
+	struct metal_ctx *ctx = (struct metal_ctx *) gfx_ctx;
+
+	sync_set_interval(&ctx->sync, interval);
 }
 
 void mty_metal_ctx_present(struct gfx_ctx *gfx_ctx)
 {
 	struct metal_ctx *ctx = (struct metal_ctx *) gfx_ctx;
 
 	if (ctx->back_buffer) {
+		int64_t ctr = display_link_get_counter(&ctx->dlink);
+
 		id<MTLCommandBuffer> cb = [ctx->cq commandBuffer];
 		[cb presentDrawable:ctx->back_buffer];
 		[cb commit];
 		[cb waitUntilCompleted];
 
+		ctr = display_link_get_counter(&ctx->dlink) - ctr;
+
+		int64_t interval = sync_next_interval(&ctx->sync);
+
+		if (interval - ctr > 0)
+			display_link_delay(&ctx->dlink, interval - ctr);
+
 		ctx->back_buffer = nil;
 	}
 }

diff --git a/src/windows/gfx/d3d11-ctx.c b/src/windows/gfx/d3d11-ctx.c
@@ -196,7 +196,7 @@ struct gfx_ctx *mty_d3d11_ctx_create(void *native_window, bool vsync)
 	ctx->hwnd = (HWND) native_window;
 
 	if (vsync)
-		sync_set_interval(&ctx->sync, 1);
+		sync_set_interval(&ctx->sync, 100);
 
 	d3d11_ctx_get_size(ctx, &ctx->width, &ctx->height);
 

diff --git a/src/windows/gfx/d3d12-ctx.c b/src/windows/gfx/d3d12-ctx.c
@@ -285,7 +285,7 @@ struct gfx_ctx *mty_d3d12_ctx_create(void *native_window, bool vsync)
 	ctx->hwnd = (HWND) native_window;
 
 	if (vsync)
-		sync_set_interval(&ctx->sync, 1);
+		sync_set_interval(&ctx->sync, 100);
 
 	d3d12_ctx_get_size(ctx, &ctx->width, &ctx->height);