1 files changed, 34 insertions, 4 deletions
diff --git a/libmpv/opengl_cb.h b/libmpv/opengl_cb.h
index 799e353a41..1434c6cee3 100644
--- a/libmpv/opengl_cb.h
+++ b/libmpv/opengl_cb.h
@@ -151,6 +151,24 @@ extern "C" {
  * up until mpv_opengl_cb_uninit_gl() is called. If the name is not anything
  * you know/expected, return NULL from the function.
  *
+ * * Windowing system scaling
+ * ------------------------------------
+ *
+ * When using GL, sometimes GL rendering window is upscaled to display buffer.
+ * Typically with drm where GL framebuffer can be upscaled at later stage.
+ * In That case glMPGetNativeDisplay("opengl-cb-window-pos") should return an
+ * mpv_opengl_cb_window_pos struct pointer defined below.
+ * Note : The intended use is for hardware overlays that might require
+ * upscaling features (typically upscaling GL windows with drm to screen size).
+ */
+struct mpv_opengl_cb_window_pos {
+    int x;      // left coordinates of window (usually 0)
+    int y;      // top coordinates of window (usually 0)
+    int width;  // width of GL window
+    int height; // height of GL window
+};
+
+/**
  * Windowing system interop on Intel/Linux with VAAPI
  * --------------------------------------------------
  *
@@ -163,10 +181,22 @@ extern "C" {
  *
  * glMPGetNativeDisplay("wl") should return a Wayland "struct wl_display *".
  *
- * glMPGetNativeDisplay("drm") should return a DRM FD casted to intptr_t (note
- * that a 0 FD is not supported - if this can happen in your case, you must
- * dup2() it to a non-0 FD).
- *
+ * glMPGetNativeDisplay("opengl-cb-drm-params") should return an
+ * mpv_opengl_cb_drm_params structure pointer :
+ */
+struct mpv_opengl_cb_drm_params {
+    // DRM fd (int). set this to -1 if invalid.
+    int fd;
+
+    // currently used crtc id
+    int crtc_id;
+
+    // pointer to the drmModeAtomicReq that is being used for the renderloop.
+    // This atomic request pointer should be usually created at every renderloop.
+    struct _drmModeAtomicReq *atomic_request;
+};
+
+/**
  * nVidia/Linux via VDPAU requires GLX, which does not have this problem (the
  * GLX API can return the current X11 Display).
  *