From 3d8a7e4c15bb8e1340157b73831266c9e79ff12d Mon Sep 17 00:00:00 2001
From: Steven Noonan <steven@uplinklabs.net>
Date: Fri, 9 Apr 2021 07:44:38 -0700
Subject: [PATCH] cocoa: implement GL_GetDrawableSize for OpenGL ES

---
 src/video/cocoa/SDL_cocoaopengles.h |  2 ++
 src/video/cocoa/SDL_cocoaopengles.m | 23 ++++++++++++++++++++++-
 src/video/cocoa/SDL_cocoavideo.m    |  1 +
 src/video/cocoa/SDL_cocoawindow.m   |  7 +++++++
 4 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/src/video/cocoa/SDL_cocoaopengles.h b/src/video/cocoa/SDL_cocoaopengles.h
index 05800e3e42..4b3b53cc66 100644
--- a/src/video/cocoa/SDL_cocoaopengles.h
+++ b/src/video/cocoa/SDL_cocoaopengles.h
@@ -39,6 +39,8 @@ extern int Cocoa_GLES_LoadLibrary(_THIS, const char *path);
 extern SDL_GLContext Cocoa_GLES_CreateContext(_THIS, SDL_Window * window);
 extern int Cocoa_GLES_SwapWindow(_THIS, SDL_Window * window);
 extern int Cocoa_GLES_MakeCurrent(_THIS, SDL_Window * window, SDL_GLContext context);
+extern void Cocoa_GLES_GetDrawableSize(_THIS, SDL_Window * window,
+                                     int * w, int * h);
 extern void Cocoa_GLES_DeleteContext(_THIS, SDL_GLContext context);
 extern int Cocoa_GLES_SetupWindow(_THIS, SDL_Window * window);
 extern SDL_EGLSurface Cocoa_GLES_GetEGLSurface(_THIS, SDL_Window * window);
diff --git a/src/video/cocoa/SDL_cocoaopengles.m b/src/video/cocoa/SDL_cocoaopengles.m
index b8f17282d2..6df958f1db 100644
--- a/src/video/cocoa/SDL_cocoaopengles.m
+++ b/src/video/cocoa/SDL_cocoaopengles.m
@@ -114,8 +114,29 @@ Cocoa_GLES_MakeCurrent(_THIS, SDL_Window * window, SDL_GLContext context)
     return SDL_EGL_MakeCurrent(_this, window ? ((__bridge SDL_WindowData *) window->driverdata).egl_surface : EGL_NO_SURFACE, context);
 }}
 
+void
+Cocoa_GLES_GetDrawableSize(_THIS, SDL_Window * window, int * w, int * h)
+{ @autoreleasepool
+{
+    SDL_WindowData *windata = (__bridge SDL_WindowData *)window->driverdata;
+    NSView *contentView = windata.nswindow.contentView;
+    CALayer *layer = [contentView layer];
+
+    int width = layer.bounds.size.width * layer.contentsScale;
+    int height = layer.bounds.size.height * layer.contentsScale;
+
+    if (w) {
+        *w = width;
+    }
+
+    if (h) {
+        *h = height;
+    }
+}}
+
 int
 Cocoa_GLES_SetupWindow(_THIS, SDL_Window * window)
+{ @autoreleasepool
 {
     NSView* v;
     /* The current context is lost in here; save it and reset it. */
@@ -145,7 +166,7 @@ Cocoa_GLES_SetupWindow(_THIS, SDL_Window * window)
     }
 
     return Cocoa_GLES_MakeCurrent(_this, current_win, current_ctx);
-}
+}}
 
 SDL_EGLSurface
 Cocoa_GLES_GetEGLSurface(_THIS, SDL_Window * window)
diff --git a/src/video/cocoa/SDL_cocoavideo.m b/src/video/cocoa/SDL_cocoavideo.m
index a354a2451e..da43da732e 100644
--- a/src/video/cocoa/SDL_cocoavideo.m
+++ b/src/video/cocoa/SDL_cocoavideo.m
@@ -150,6 +150,7 @@ Cocoa_CreateDevice(void)
         device->GL_UnloadLibrary = Cocoa_GLES_UnloadLibrary;
         device->GL_CreateContext = Cocoa_GLES_CreateContext;
         device->GL_MakeCurrent = Cocoa_GLES_MakeCurrent;
+        device->GL_GetDrawableSize = Cocoa_GLES_GetDrawableSize;
         device->GL_SetSwapInterval = Cocoa_GLES_SetSwapInterval;
         device->GL_GetSwapInterval = Cocoa_GLES_GetSwapInterval;
         device->GL_SwapWindow = Cocoa_GLES_SwapWindow;
diff --git a/src/video/cocoa/SDL_cocoawindow.m b/src/video/cocoa/SDL_cocoawindow.m
index eea7f981a6..7d5ee09316 100644
--- a/src/video/cocoa/SDL_cocoawindow.m
+++ b/src/video/cocoa/SDL_cocoawindow.m
@@ -1787,6 +1787,13 @@ Cocoa_CreateWindow(_THIS, SDL_Window * window)
     if ((window->flags & SDL_WINDOW_OPENGL) &&
         _this->gl_config.profile_mask == SDL_GL_CONTEXT_PROFILE_ES) {
         [contentView setWantsLayer:TRUE];
+        if (!(window->flags & SDL_WINDOW_ALLOW_HIGHDPI)) {
+            contentView.layer.contentsScale = 1;
+        } else {
+            if ([nswindow.screen respondsToSelector:@selector(backingScaleFactor)]) {
+                contentView.layer.contentsScale = nswindow.screen.backingScaleFactor;
+            }
+        }
     }
 #endif /* SDL_VIDEO_OPENGL_EGL */
 #endif /* SDL_VIDEO_OPENGL_ES2 */