output: add wlr_output_get_primary_formats

This allows compositors to get primary formats without manually
calling wlr_output_impl.get_primary_formats.

For example, the Sway patch for linux-dmabuf feedback [1] needs
this.

[1]: https://github.com/swaywm/sway/pull/6313

1 files changed, 10 insertions, 0 deletions

diff --git a/include/wlr/types/wlr_output.h b/include/wlr/types/wlr_output.h
index 7d7fbaad..9e18a216 100644
--- a/include/wlr/types/wlr_output.h
+++ b/include/wlr/types/wlr_output.h
@@ -460,6 +460,16 @@ void wlr_output_lock_software_cursors(struct wlr_output *output, bool lock);
  */
 void wlr_output_render_software_cursors(struct wlr_output *output,
 	pixman_region32_t *damage);
+/**
+ * Get the set of DRM formats suitable for the primary buffer, assuming a
+ * buffer with the specified capabilities.
+ *
+ * NULL is returned if the backend doesn't have any format constraint, ie. all
+ * formats are supported. An empty set is returned if the backend doesn't
+ * support any format.
+ */
+const struct wlr_drm_format_set *wlr_output_get_primary_formats(
+	struct wlr_output *output, uint32_t buffer_caps);
 
 
 struct wlr_output_cursor *wlr_output_cursor_create(struct wlr_output *output);