Controller API support (#158)

* Initial lowlevel controller API and timed value controller mappings / pointer types.

* Add missing GstDirectControlBinding support to lowlevel.

* Add Natives.objectFor and Natives.callerOwnsReturn variants that accept GPointer directly.

* Add ControlSource and ControlBinding base classes; add GstObject support for control bindings; add DirectControlBinding, TimedValueControlSource (incomplete) and InterpolationControlSource.

* Add GstTimedValue structure and Java equivalent; add bulk set and get support to TimedValueControlSource.

* Add LFOControlSource

* Add GTYPE_NAME and registration.

* Return boolean from GstObject::syncValues as upstream - use with trigger control source is awkward otherwise.

* Add some testing of interpolation control source.

* Add TriggerControlSource with simple test.

* Return this on property setting for easier method chaining.

* Implement ARGBControlBinding mapping.

* Add ProxyControlBinding mapping.

src/org/freedesktop/gstreamer/ControlBinding.java

@@ -0,0 +1,126 @@
+/* 
+ * Copyright (c) 2019 Neil C Smith
+ * 
+ * This file is part of gstreamer-java.
+ *
+ * This code is free software: you can redistribute it and/or modify it under 
+ * the terms of the GNU Lesser General Public License version 3 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code 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 Lesser General Public License 
+ * version 3 for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * version 3 along with this work.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.freedesktop.gstreamer;
+
+import org.freedesktop.gstreamer.lowlevel.GValueAPI;
+import org.freedesktop.gstreamer.lowlevel.GstControlBindingPtr;
+
+import static org.freedesktop.gstreamer.lowlevel.GstControlBindingAPI.GSTCONTROLBINDING_API;
+
+/**
+ * Attachment for control source sources.
+ * <p>
+ * See upstream documentation at
+ * <a href="https://gstreamer.freedesktop.org/data/doc/gstreamer/stable/gstreamer/html/GstControlBinding.html"
+ * >https://gstreamer.freedesktop.org/data/doc/gstreamer/stable/gstreamer/html/GstControlBinding.html</a>
+ * <p>
+ */
+public class ControlBinding extends GstObject {
+
+    public static final String GTYPE_NAME = "GstControlBinding";
+
+    private final Handle handle;
+
+    protected ControlBinding(Handle handle, boolean needRef) {
+        super(handle, needRef);
+        this.handle = handle;
+    }
+
+    ControlBinding(Initializer init) {
+        this(new Handle(
+                init.ptr.as(GstControlBindingPtr.class, GstControlBindingPtr::new),
+                init.ownsHandle),
+                init.needRef);
+    }
+
+    /**
+     * Gets the value for the given controlled property at the requested time.
+     *
+     * @param timestamp the time the control-change should be read from
+     * @return the value of the property at the given time, or NULL if the
+     * property isn't controlled
+     */
+    public Object getValue(long timestamp) {
+        GValueAPI.GValue gValue = GSTCONTROLBINDING_API.gst_control_binding_get_value(
+                handle.getPointer(), timestamp);
+        return gValue == null ? null : gValue.getValue();
+    }
+
+    /**
+     * Gets a number of values for the given controlled property starting at
+     * the requested time.
+     * <p>
+     * This function is useful if one wants to e.g. draw a graph of the control
+     * curve or apply a control curve sample by sample.
+     * 
+     * @param timestamp the time that should be processed
+     * @param interval the time spacing between subsequent values
+     * @param values array to fill with control values
+     * @return false if the given array could not be filled
+     */
+    public boolean getValueArray(long timestamp, long interval, Object[] values) {
+        GValueAPI.GValueArray gValues = new GValueAPI.GValueArray(values.length);
+        boolean ok = GSTCONTROLBINDING_API.gst_control_binding_get_g_value_array(
+                handle.getPointer(),
+                timestamp,
+                interval,
+                gValues.n_values,
+                gValues);
+        if (ok) {
+            for (int i = 0; i < values.length; i++) {
+                values[i] = gValues.getValue(i);
+            }
+        }
+        return ok;
+    }
+
+    /**
+     * This function is used to disable a control binding for some time, i.e.
+     * GstObject.syncValues() will do nothing.
+     * 
+     * @param disabled whether to disable the controller or not
+     */
+    public void setDisabled(boolean disabled) {
+        GSTCONTROLBINDING_API.gst_control_binding_set_disabled(handle.getPointer(), disabled);
+    }
+
+    /**
+     * Check if the control binding is disabled.
+     * 
+     * @return TRUE if the binding is inactive
+     */
+    public boolean isDisabled() {
+        return GSTCONTROLBINDING_API.gst_control_binding_is_disabled(handle.getPointer());
+
+    }
+
+
+    protected static class Handle extends GstObject.Handle {
+
+        public Handle(GstControlBindingPtr ptr, boolean ownsHandle) {
+            super(ptr, ownsHandle);
+        }
+
+        @Override
+        protected GstControlBindingPtr getPointer() {
+            return (GstControlBindingPtr) super.getPointer();
+        }
+
+    }
+
+}

src/org/freedesktop/gstreamer/ControlSource.java

@@ -0,0 +1,160 @@
+/* 
+ * Copyright (c) 2019 Neil C Smith
+ * 
+ * This file is part of gstreamer-java.
+ *
+ * This code is free software: you can redistribute it and/or modify it under 
+ * the terms of the GNU Lesser General Public License version 3 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code 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 Lesser General Public License 
+ * version 3 for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * version 3 along with this work.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.freedesktop.gstreamer;
+
+import org.freedesktop.gstreamer.lowlevel.GstControlSourcePtr;
+
+import static org.freedesktop.gstreamer.lowlevel.GstControlSourceAPI.GSTCONTROLSOURCE_API;
+
+/**
+ * Base class for control source sources.
+ * <p>
+ * See upstream documentation at
+ * <a href="https://gstreamer.freedesktop.org/data/doc/gstreamer/stable/gstreamer/html/GstControlSource.html"
+ * >https://gstreamer.freedesktop.org/data/doc/gstreamer/stable/gstreamer/html/GstControlSource.html</a>
+ * <p>
+ */
+public class ControlSource extends GstObject {
+
+    public static final String GTYPE_NAME = "GstControlSource";
+
+    private final Handle handle;
+
+    protected ControlSource(Handle handle, boolean needRef) {
+        super(handle, needRef);
+        this.handle = handle;
+    }
+
+    ControlSource(Initializer init) {
+        this(new Handle(
+                init.ptr.as(GstControlSourcePtr.class, GstControlSourcePtr::new),
+                init.ownsHandle),
+                init.needRef);
+    }
+
+    /**
+     * Gets the value for this ControlSource at a given timestamp.
+     *
+     * @param timestamp the time for which the value should be returned
+     * @return value
+     * @throws IllegalStateException if the value could not be calculated
+     */
+    public double getValue(long timestamp) {
+        double[] out = new double[1];
+        boolean ok = GSTCONTROLSOURCE_API.gst_control_source_get_value(handle.getPointer(), timestamp, out);
+        if (ok) {
+            return out[0];
+        } else {
+            throw new IllegalStateException();
+        }
+    }
+
+    /**
+     * Gets an array of values for for this ControlSource. Values that are
+     * undefined contain NANs.
+     *
+     * @param timestamp the first timestamp
+     * @param interval the time steps
+     * @param values array to put control-values in
+     * @return true if the values were successfully calculated
+     */
+    public boolean getValueArray(long timestamp, long interval, double[] values) {
+        return GSTCONTROLSOURCE_API.gst_control_source_get_value_array(
+                handle.getPointer(),
+                timestamp,
+                interval,
+                values.length,
+                values);
+    }
+
+    /**
+     * A simple structure for saving a timestamp and a value.
+     * <p>
+     * Equivalent to GstTimedValue.
+     * <p>
+     * <a href="https://gstreamer.freedesktop.org/data/doc/gstreamer/stable/gstreamer/html/GstControlSource.html#GstTimedValue"
+     * >https://gstreamer.freedesktop.org/data/doc/gstreamer/stable/gstreamer/html/GstControlSource.html#GstTimedValue</a>
+     *
+     */
+    public static final class TimedValue {
+
+        public final long timestamp;
+        public final double value;
+
+        /**
+         * Create a TimedValue wrapping the timestamp (see {@link ClockTime})
+         * and corresponding value.
+         *
+         * @param timestamp the timestamp (GstClockTime) of the value change
+         * @param value the corresponding value
+         */
+        public TimedValue(long timestamp, double value) {
+            this.timestamp = timestamp;
+            this.value = value;
+        }
+
+        @Override
+        public int hashCode() {
+            int hash = 7;
+            hash = 37 * hash + (int) (this.timestamp ^ (this.timestamp >>> 32));
+            hash = 37 * hash + (int) (Double.doubleToLongBits(this.value) ^ (Double.doubleToLongBits(this.value) >>> 32));
+            return hash;
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            if (this == obj) {
+                return true;
+            }
+            if (obj == null) {
+                return false;
+            }
+            if (getClass() != obj.getClass()) {
+                return false;
+            }
+            final TimedValue other = (TimedValue) obj;
+            if (this.timestamp != other.timestamp) {
+                return false;
+            }
+            if (Double.doubleToLongBits(this.value) != Double.doubleToLongBits(other.value)) {
+                return false;
+            }
+            return true;
+        }
+
+        @Override
+        public String toString() {
+            return "TimedValue{" + "timestamp=" + timestamp + ", value=" + value + '}';
+        }
+
+    }
+
+    protected static class Handle extends GstObject.Handle {
+
+        public Handle(GstControlSourcePtr ptr, boolean ownsHandle) {
+            super(ptr, ownsHandle);
+        }
+
+        @Override
+        protected GstControlSourcePtr getPointer() {
+            return (GstControlSourcePtr) super.getPointer();
+        }
+
+    }
+
+}

src/org/freedesktop/gstreamer/Gst.java

@@ -52,6 +52,7 @@
 import java.util.ServiceLoader;
 import java.util.logging.Level;
 import java.util.stream.Stream;
+import org.freedesktop.gstreamer.controller.Controllers;
 import org.freedesktop.gstreamer.elements.Elements;
 import org.freedesktop.gstreamer.glib.GLib;
 import org.freedesktop.gstreamer.glib.GMainContext;
@@ -666,6 +667,7 @@ private static synchronized void loadAllClasses() {
                 new Event.Types(),
                 new Message.Types(),
                 new Query.Types(),
+                new Controllers(),
                 new Elements(),
                 new WebRTC.Types())
                 .flatMap(NativeObject.TypeProvider::types)