From 5a158952d507653ac8b900764a633afdb7e922f4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kacper=20Michaj=C5=82ow?= <kasper93@gmail.com>
Date: Tue, 22 Aug 2023 00:12:33 +0200
Subject: [PATCH] win32: add --window-corners

Allows to set preference for window corners rounding for DWM.
---
 DOCS/interface-changes.rst |  1 +
 DOCS/man/options.rst       |  9 +++++++++
 options/options.c          | 11 +++++++++++
 options/options.h          |  1 +
 video/out/w32_common.c     | 11 +++++++++++
 5 files changed, 33 insertions(+)

diff --git a/DOCS/interface-changes.rst b/DOCS/interface-changes.rst
index ad0e059ef1697..b44b452b94071 100644
--- a/DOCS/interface-changes.rst
+++ b/DOCS/interface-changes.rst
@@ -88,6 +88,7 @@ Interface changes
     - `--drm-connector` no longer allows selecting the card number (use `--drm-device`
       instead)
     - add `--title-bar` option
+    - add `--window-corners` option
  --- mpv 0.36.0 ---
     - add `--target-contrast`
     - Target luminance value is now also applied when ICC profile is used.
diff --git a/DOCS/man/options.rst b/DOCS/man/options.rst
index 8e59ac1dbc742..20ba4f8552685 100644
--- a/DOCS/man/options.rst
+++ b/DOCS/man/options.rst
@@ -3131,6 +3131,15 @@ Window
     Focus the video window on creation and makes it the front most window. This
     is on by default.
 
+``--window-corners=<default|donotround|round|roundsmall>``
+    (Windows only)
+    Set the preference for window corner rounding.
+
+    :default: Let the system decide whether or not to round window corners
+    :donotround: Never round window corners
+    :round: Round the corners if appropriate
+    :roundsmall: Round the corners if appropriate, with a small radius
+
 ``--border``, ``--no-border``
     Play video with window border and decorations. Since this is on by
     default, use ``--no-border`` to disable the standard window decorations.
diff --git a/options/options.c b/options/options.c
index 357f043404187..40f1f6ff83f2d 100644
--- a/options/options.c
+++ b/options/options.c
@@ -32,6 +32,7 @@
 
 #ifdef _WIN32
 #include <windows.h>
+#include <dwmapi.h>
 #endif
 
 #include "options.h"
@@ -190,6 +191,16 @@ static const m_option_t mp_vo_opt_list[] = {
     {"window-affinity", OPT_CHOICE(window_affinity, {"default", WDA_NONE},
         {"excludefromcapture", WDA_EXCLUDEFROMCAPTURE}, {"monitor", WDA_MONITOR})},
     {"vo-mmcss-profile", OPT_STRING(mmcss_profile)},
+// For old MinGW-w64 compatibility
+#define DWMWCP_DEFAULT 0
+#define DWMWCP_DONOTROUND 1
+#define DWMWCP_ROUND 2
+#define DWMWCP_ROUNDSMALL 3
+    {"window-corners", OPT_CHOICE(window_corners,
+        {"default", DWMWCP_DEFAULT},
+        {"donotround", DWMWCP_DONOTROUND},
+        {"round", DWMWCP_ROUND},
+        {"roundsmall", DWMWCP_ROUNDSMALL})},
 #endif
 #if HAVE_EGL_ANDROID
     {"android-surface-size", OPT_SIZE_BOX(android_surface_size)},
diff --git a/options/options.h b/options/options.h
index ce676840edc5e..339acda38c1a2 100644
--- a/options/options.h
+++ b/options/options.h
@@ -66,6 +66,7 @@ typedef struct mp_vo_opts {
 
     int window_affinity;
     char *mmcss_profile;
+    int window_corners;
 
     double override_display_fps;
     double timing_offset;
diff --git a/video/out/w32_common.c b/video/out/w32_common.c
index ee00972ba3ded..b288adf253e42 100644
--- a/video/out/w32_common.c
+++ b/video/out/w32_common.c
@@ -58,6 +58,8 @@ EXTERN_C IMAGE_DOS_HEADER __ImageBase;
 #define DWMWA_USE_IMMERSIVE_DARK_MODE 20
 #endif
 
+#define DWMWA_WINDOW_CORNER_PREFERENCE 33
+
 #ifndef DPI_ENUMS_DECLARED
 typedef enum MONITOR_DPI_TYPE {
     MDT_EFFECTIVE_DPI = 0,
@@ -1090,6 +1092,12 @@ static void update_dark_mode(const struct vo_w32_state *w32)
                           &use_dark_mode, sizeof(use_dark_mode));
 }
 
+static void update_corners_pref(const struct vo_w32_state *w32) {
+    DwmSetWindowAttribute(w32->window, DWMWA_WINDOW_CORNER_PREFERENCE,
+                          &w32->opts->window_corners,
+                          sizeof(w32->opts->window_corners));
+}
+
 static LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam,
                                 LPARAM lParam)
 {
@@ -1666,6 +1674,7 @@ static void *gui_thread(void *ptr)
     }
 
     update_dark_mode(w32);
+    update_corners_pref(w32);
     if (w32->opts->window_affinity)
         update_affinity(w32);
 
@@ -1855,6 +1864,8 @@ static int gui_thread_control(struct vo_w32_state *w32, int request, void *arg)
                 update_minimized_state(w32);
             } else if (changed_option == &vo_opts->window_maximized) {
                 update_maximized_state(w32);
+            } else if (changed_option == &vo_opts->window_corners) {
+                update_corners_pref(w32);
             }
         }