Implement IParamValueQueue

2026-05-08 12:30:12 +02:00 · 2020-12-15 14:01:04 +01:00
parent e7d7317f60
commit 026595d99f
5 changed files with 171 additions and 0 deletions
@@ -0,0 +1,86 @@
+// yabridge: a Wine VST bridge
+// Copyright (C) 2020  Robbert van der Helm
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+#pragma once
+
+#include <bitsery/traits/vector.h>
+#include <pluginterfaces/vst/ivstparameterchanges.h>
+
+#include "base.h"
+
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
+
+/**
+ * Wraps around `IParamValueQueue` for serializing a queue containing changes to
+ * a single parameter during the current processing cycle. Used in
+ * `YaParameterChanges`.
+ */
+class YaParamValueQueue : public Steinberg::Vst::IParamValueQueue {
+   public:
+    /**
+     * Default constructor with an empty queue.
+     */
+    YaParamValueQueue();
+
+    /**
+     * Read data from an existing `IParamValueQueue` object.
+     */
+    YaParamValueQueue(Steinberg::Vst::IParamValueQueue&);
+
+    ~YaParamValueQueue();
+
+    DECLARE_FUNKNOWN_METHODS
+
+    // From `IParamValueQueue`
+    Steinberg::Vst::ParamID PLUGIN_API getParameterId() override;
+    int32 PLUGIN_API getPointCount() override;
+    tresult PLUGIN_API
+    getPoint(int32 index,
+             int32& sampleOffset /*out*/,
+             Steinberg::Vst::ParamValue& value /*out*/) override;
+    tresult PLUGIN_API addPoint(int32 sampleOffset,
+                                Steinberg::Vst::ParamValue value,
+                                int32& index /*out*/) override;
+
+    template <typename S>
+    void serialize(S& s) {
+        s.value4b(parameter_id);
+        // TODO: Does bitsery have a built in way to serialize pairs?
+        s.container(queue, 1 << 16, [](S& s, std::pair<int32, double>& pair) {
+            s.value4b(pair.first);
+            s.value8b(pair.second);
+        });
+    }
+
+   private:
+    /**
+     * For `IParamValueQueue::getParameterId`.
+     */
+    Steinberg::Vst::ParamID parameter_id;
+
+    /**
+     * The actual parameter changes queue. The specification doesn't mention
+     * that this should be a priority queue or something, but I'd assume both
+     * the plugin and the host will insert the values in chronological order
+     * (because, why would they not?).
+     *
+     * This contains pairs of `(sample_offset, value)`.
+     */
+    std::vector<std::pair<int32, Steinberg::Vst::ParamValue>> queue;
+};
+
+#pragma GCC diagnostic pop