Merge pull request #2072 from RyanDwyer/atomic

Atomic layout updates

1 files changed, 67 insertions, 0 deletions

diff --git a/include/sway/desktop/transaction.h b/include/sway/desktop/transaction.h
new file mode 100644
index 00000000..7ab80eb8
--- /dev/null
+++ b/include/sway/desktop/transaction.h
@@ -0,0 +1,67 @@
+#ifndef _SWAY_TRANSACTION_H
+#define _SWAY_TRANSACTION_H
+#include <wlr/render/wlr_texture.h>
+#include "sway/tree/container.h"
+
+/**
+ * Transactions enable us to perform atomic layout updates.
+ *
+ * When we want to make adjustments to the layout, we create a transaction.
+ * A transaction contains a list of affected containers and their new state.
+ * A state might contain a new size, or new border settings, or new parent/child
+ * relationships.
+ *
+ * Calling transaction_commit() makes sway notify of all the affected clients
+ * with their new sizes. We then wait for all the views to respond with their
+ * new surface sizes. When all are ready, or when a timeout has passed, we apply
+ * the updates all at the same time.
+ */
+
+struct sway_transaction;
+
+/**
+ * Create a new transaction.
+ */
+struct sway_transaction *transaction_create(void);
+
+/**
+ * Add a container's pending state to the transaction.
+ */
+void transaction_add_container(struct sway_transaction *transaction,
+		struct sway_container *container);
+
+/**
+ * Submit a transaction to the client views for configuration.
+ */
+void transaction_commit(struct sway_transaction *transaction);
+
+/**
+ * Notify the transaction system that a view is ready for the new layout.
+ *
+ * When all views in the transaction are ready, the layout will be applied.
+ */
+void transaction_notify_view_ready(struct sway_view *view, uint32_t serial);
+
+/**
+ * Notify the transaction system that a view is ready for the new layout, but
+ * identifying the instruction by width and height rather than by serial.
+ *
+ * This is used by xwayland views, as they don't have serials.
+ */
+void transaction_notify_view_ready_by_size(struct sway_view *view,
+		int width, int height);
+
+/**
+ * Get the saved texture that should be rendered for a view.
+ *
+ * The addresses pointed at by the width and height pointers will be populated
+ * with the surface's dimensions, which may be different to the texture's
+ * dimensions if output scaling is used.
+ *
+ * This function should only be called if it is known that the view has
+ * instructions.
+ */
+struct wlr_texture *transaction_get_saved_texture(struct sway_view *view,
+		int *width, int *height);
+
+#endif