clap

commit 923c31c211b3c3c11e58a1cf1c467423a29d251a
parent 09b7b8dab5cfe63c37960e4688735c065a255adc
Author: Alexandre Bique <bique.alexandre@gmail.com>
Date:   Mon, 12 Dec 2022 12:42:13 +0100

Merge pull request #220 from abique/audio-port-activation

Audio port activation
Diffstat:
A
include/clap/ext/draft/audio-ports-activation.h
 | 
46
++++++++++++++++++++++++++++++++++++++++++++++

1 file changed, 46 insertions(+), 0 deletions(-)
diff --git a/include/clap/ext/draft/audio-ports-activation.h b/include/clap/ext/draft/audio-ports-activation.h
@@ -0,0 +1,46 @@
+#pragma once
+
+#include "../../plugin.h"
+
+/// @page Audio Ports Activation
+///
+/// This extension provides a way for the host to activate and de-activate audio ports.
+/// Deactivating a port provides the following benefits:
+/// - the plugin knows ahead of time that a given input is not present and can choose
+///   an optimized computation path
+/// - the plugin knows that an output is not consumed by the host, and doesn't need to
+///   compute it
+///
+/// Audio ports can only be activated or deactivated when the plugin is deactivated, unless
+/// can_activate_while_processing() returns true.
+///
+/// Audio buffers must still be provided if the audio port is deactivated.
+/// In such case, they shall be filled with 0 (or whatever is the neutral value in your context)
+/// and the constant_mask shall be set.
+///
+/// Audio ports are initially in the active state.
+/// Audio ports state should not be saved in the plugin state, so the host must restore the
+/// audio ports state after creating the plugin instance.
+///
+/// Audio ports state is invalidated by clap_plugin_audio_ports_config.select() and
+/// clap_host_audio_ports.rescan(CLAP_AUDIO_PORTS_RESCAN_LIST).
+
+static CLAP_CONSTEXPR const char CLAP_EXT_AUDIO_PORTS_ACTIVATION[] = "clap.audio-ports-activation/draft-0";
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct clap_plugin_audio_ports_activation {
+   // returns true if the plugin supports activation/deactivation while processing.
+   // [main-thread]
+   bool(CLAP_ABI *can_activate_while_processing)(const clap_plugin_t *plugin);
+
+   // activate the given port
+   // [main-thread]
+   uint32_t(CLAP_ABI *set_active)(const clap_plugin_t *plugin, bool is_input, uint32_t port_index, bool is_active);
+} clap_plugin_audio_ports_activation_t;
+
+#ifdef __cplusplus
+}
+#endif