Adjust things for better external ui support, add example plugin

Signed-off-by: falkTX <falktx@gmail.com>

13 files changed, 696 insertions, 100 deletions

diff --git a/Makefile b/Makefile
index e27a4936..cf1b0cbc 100644
--- a/Makefile
+++ b/Makefile
@@ -16,6 +16,7 @@ ifeq ($(HAVE_DGL),true)
 endif
 
 examples: dgl
+	$(MAKE) all -C examples/ExternalUI
 	$(MAKE) all -C examples/Info
 	$(MAKE) all -C examples/Latency
 	$(MAKE) all -C examples/Meters
@@ -23,6 +24,13 @@ examples: dgl
 	$(MAKE) all -C examples/Parameters
 	$(MAKE) all -C examples/States
 
+	# ExternalUI launcher
+	install -d bin/d_extui-dssi
+	install -d bin/d_extui.lv2
+	install -m 755 examples/ExternalUI/ExternalLauncher.sh bin/d_extui.sh
+	install -m 755 examples/ExternalUI/ExternalLauncher.sh bin/d_extui-dssi/d_extui.sh
+	install -m 755 examples/ExternalUI/ExternalLauncher.sh bin/d_extui.lv2/d_extui.sh
+
 ifneq ($(CROSS_COMPILING),true)
 gen: examples utils/lv2_ttl_generator
 	@$(CURDIR)/utils/generate-ttl.sh
@@ -40,6 +48,7 @@ endif
 
 clean:
 	$(MAKE) clean -C dgl
+	$(MAKE) clean -C examples/ExternalUI
 	$(MAKE) clean -C examples/Info
 	$(MAKE) clean -C examples/Latency
 	$(MAKE) clean -C examples/Meters
diff --git a/distrho/DistrhoUI.hpp b/distrho/DistrhoUI.hpp
index e33a4ca4..244b25bc 100644
--- a/distrho/DistrhoUI.hpp
+++ b/distrho/DistrhoUI.hpp
@@ -1,6 +1,6 @@
 /*
  * DISTRHO Plugin Framework (DPF)
- * Copyright (C) 2012-2016 Filipe Coelho <falktx@falktx.com>
+ * Copyright (C) 2012-2018 Filipe Coelho <falktx@falktx.com>
  *
  * Permission to use, copy, modify, and/or distribute this software for any purpose with
  * or without fee is hereby granted, provided that the above copyright notice and this
@@ -20,7 +20,8 @@
 #include "extra/LeakDetector.hpp"
 #include "src/DistrhoPluginChecks.h"
 
-#ifndef HAVE_DGL
+#if DISTRHO_PLUGIN_HAS_EXTERNAL_UI
+# include "../dgl/Base.hpp"
 # include "extra/ExternalWindow.hpp"
 typedef DISTRHO_NAMESPACE::ExternalWindow UIWidget;
 #elif DISTRHO_UI_USE_NANOVG
@@ -67,7 +68,7 @@ public:
     */
     bool isUserResizable() const noexcept;
 
-#ifdef HAVE_DGL
+#if !DISTRHO_PLUGIN_HAS_EXTERNAL_UI
    /**
       Set geometry constraints for the UI when resized by the user, and optionally scale UI automatically.
       @see Window::setGeometryConstraints(uint,uint,bool)
@@ -181,7 +182,7 @@ protected:
     */
     virtual void sampleRateChanged(double newSampleRate);
 
-#ifdef HAVE_DGL
+#if !DISTRHO_PLUGIN_HAS_EXTERNAL_UI
    /* --------------------------------------------------------------------------------------------------------
     * UI Callbacks (optional) */
 
@@ -191,13 +192,13 @@ protected:
     */
     virtual void uiIdle() {}
 
-#ifndef DGL_FILE_BROWSER_DISABLED
+# ifndef DGL_FILE_BROWSER_DISABLED
    /**
       File browser selected function.
       @see Window::fileBrowserSelected(const char*)
     */
     virtual void uiFileBrowserSelected(const char* filename);
-#endif
+# endif
 
    /**
       OpenGL window reshape function, called when parent window is resized.
@@ -225,7 +226,7 @@ private:
     friend class UIExporter;
     friend class UIExporterWindow;
 
-#ifdef HAVE_DGL
+#if !DISTRHO_PLUGIN_HAS_EXTERNAL_UI
     // these should not be used
     void setAbsoluteX(int) const noexcept {}
     void setAbsoluteY(int) const noexcept {}
diff --git a/distrho/extra/ExternalWindow.hpp b/distrho/extra/ExternalWindow.hpp
index 8ad2df0f..c39f55c7 100644
--- a/distrho/extra/ExternalWindow.hpp
+++ b/distrho/extra/ExternalWindow.hpp
@@ -40,6 +40,8 @@ public:
         : width(w),
           height(h),
           title(t),
+          transientWinId(0),
+          visible(false),
           pid(0) {}
 
     virtual ~ExternalWindow()
@@ -62,9 +64,14 @@ public:
         return title;
     }
 
-    void setTitle(const char* const t) noexcept
+    uintptr_t getTransientWinId() const noexcept
     {
-        title = t;
+        return transientWinId;
+    }
+
+    bool isVisible() const noexcept
+    {
+        return visible;
     }
 
     bool isRunning() noexcept
@@ -84,6 +91,27 @@ public:
         return true;
     }
 
+    virtual void setSize(uint w, uint h)
+    {
+        width = w;
+        height = h;
+    }
+
+    virtual void setTitle(const char* const t)
+    {
+        title = t;
+    }
+
+    virtual void setTransientWinId(const uintptr_t winId)
+    {
+        transientWinId = winId;
+    }
+
+    virtual void setVisible(const bool yesNo)
+    {
+        visible = yesNo;
+    }
+
 protected:
     bool startExternalProcess(const char* args[])
     {
@@ -107,14 +135,6 @@ protected:
         }
     }
 
-private:
-    uint width;
-    uint height;
-    String title;
-    pid_t pid;
-
-    friend class UIExporter;
-
     void terminateAndWaitForProcess()
     {
         if (pid <= 0)
@@ -162,6 +182,16 @@ private:
         }
     }
 
+private:
+    uint width;
+    uint height;
+    String title;
+    uintptr_t transientWinId;
+    bool visible;
+    pid_t pid;
+
+    friend class UIExporter;
+
     DISTRHO_DECLARE_NON_COPY_CLASS(ExternalWindow)
 };
 
diff --git a/distrho/src/DistrhoPluginJack.cpp b/distrho/src/DistrhoPluginJack.cpp
index 98ce73ca..edafaf66 100644
--- a/distrho/src/DistrhoPluginJack.cpp
+++ b/distrho/src/DistrhoPluginJack.cpp
@@ -16,11 +16,6 @@
 
 #include "DistrhoPluginInternal.hpp"
 
-#if DISTRHO_PLUGIN_HAS_UI && ! DISTRHO_PLUGIN_HAS_EMBED_UI
-# undef DISTRHO_PLUGIN_HAS_UI
-# define DISTRHO_PLUGIN_HAS_UI 0
-#endif
-
 #if DISTRHO_PLUGIN_HAS_UI
 # include "DistrhoUIInternal.hpp"
 #else
diff --git a/distrho/src/DistrhoUI.cpp b/distrho/src/DistrhoUI.cpp
index 89162d67..a9502161 100644
--- a/distrho/src/DistrhoUI.cpp
+++ b/distrho/src/DistrhoUI.cpp
@@ -1,6 +1,6 @@
 /*
  * DISTRHO Plugin Framework (DPF)
- * Copyright (C) 2012-2016 Filipe Coelho <falktx@falktx.com>
+ * Copyright (C) 2012-2018 Filipe Coelho <falktx@falktx.com>
  *
  * Permission to use, copy, modify, and/or distribute this software for any purpose with
  * or without fee is hereby granted, provided that the above copyright notice and this
@@ -15,8 +15,7 @@
  */
 
 #include "DistrhoUIInternal.hpp"
-
-#ifdef HAVE_DGL
+#if !DISTRHO_PLUGIN_HAS_EXTERNAL_UI
 # include "src/WidgetPrivateData.hpp"
 #endif
 
@@ -27,16 +26,21 @@ START_NAMESPACE_DISTRHO
 
 double      d_lastUiSampleRate = 0.0;
 void*       d_lastUiDspPtr     = nullptr;
-#ifdef HAVE_DGL
-Window*     d_lastUiWindow     = nullptr;
-#endif
+#if DISTRHO_PLUGIN_HAS_EXTERNAL_UI
 uintptr_t   g_nextWindowId     = 0;
 const char* g_nextBundlePath   = nullptr;
+#else
+Window*     d_lastUiWindow     = nullptr;
+#endif
 
 /* ------------------------------------------------------------------------------------------------------------
  * UI */
 
-#ifdef HAVE_DGL
+#if DISTRHO_PLUGIN_HAS_EXTERNAL_UI
+UI::UI(uint width, uint height, bool userResizable)
+    : UIWidget(width, height),
+      pData(new PrivateData(userResizable)) {}
+#else
 UI::UI(uint width, uint height, bool userResizable)
     : UIWidget(*d_lastUiWindow),
       pData(new PrivateData(userResizable))
@@ -46,10 +50,6 @@ UI::UI(uint width, uint height, bool userResizable)
     if (width > 0 && height > 0)
         setSize(width, height);
 }
-#else
-UI::UI(uint width, uint height, bool userResizable)
-    : UIWidget(width, height),
-      pData(new PrivateData(userResizable)) {}
 #endif
 
 UI::~UI()
@@ -62,7 +62,7 @@ bool UI::isUserResizable() const noexcept
     return pData->userResizable;
 }
 
-#ifdef HAVE_DGL
+#if !DISTRHO_PLUGIN_HAS_EXTERNAL_UI
 void UI::setGeometryConstraints(uint minWidth, uint minHeight, bool keepAspectRatio, bool automaticallyScale)
 {
     DISTRHO_SAFE_ASSERT_RETURN(minWidth > 0,);
@@ -73,7 +73,6 @@ void UI::setGeometryConstraints(uint minWidth, uint minHeight, bool keepAspectRa
     pData->minHeight = minHeight;
 
     getParentWindow().setGeometryConstraints(minWidth, minHeight, keepAspectRatio);
-
 }
 #endif
 
@@ -141,15 +140,15 @@ uintptr_t UI::getNextWindowId() noexcept
 
 void UI::sampleRateChanged(double) {}
 
-#ifdef HAVE_DGL
+#if !DISTRHO_PLUGIN_HAS_EXTERNAL_UI
 /* ------------------------------------------------------------------------------------------------------------
  * UI Callbacks (optional) */
 
-#ifndef DGL_FILE_BROWSER_DISABLED
+# ifndef DGL_FILE_BROWSER_DISABLED
 void UI::uiFileBrowserSelected(const char*)
 {
 }
-#endif
+# endif
 
 void UI::uiReshape(uint width, uint height)
 {
@@ -173,7 +172,7 @@ void UI::onResize(const ResizeEvent& ev)
 
     pData->setSizeCallback(ev.size.getWidth(), ev.size.getHeight());
 }
-#endif
+#endif // !DISTRHO_PLUGIN_HAS_EXTERNAL_UI
 
 // -----------------------------------------------------------------------------------------------------------
 
diff --git a/distrho/src/DistrhoUIDSSI.cpp b/distrho/src/DistrhoUIDSSI.cpp
index b11e1d0f..1ff4b47d 100644
--- a/distrho/src/DistrhoUIDSSI.cpp
+++ b/distrho/src/DistrhoUIDSSI.cpp
@@ -112,6 +112,7 @@ public:
 
     void exec()
     {
+        d_stdout("exec 1");
         for (;;)
         {
             fOscData.idle();
@@ -121,6 +122,7 @@ public:
 
             d_msleep(30);
         }
+        d_stdout("exec 3");
     }
 
     // -------------------------------------------------------------------
diff --git a/distrho/src/DistrhoUIInternal.hpp b/distrho/src/DistrhoUIInternal.hpp
index a7a8ac3b..4ea26580 100644
--- a/distrho/src/DistrhoUIInternal.hpp
+++ b/distrho/src/DistrhoUIInternal.hpp
@@ -19,7 +19,10 @@
 
 #include "../DistrhoUI.hpp"
 
-#ifdef HAVE_DGL
+#if DISTRHO_PLUGIN_HAS_EXTERNAL_UI
+# include "../extra/Sleep.hpp"
+using DGL_NAMESPACE::IdleCallback;
+#else
 # include "../../dgl/Application.hpp"
 # include "../../dgl/Window.hpp"
 using DGL_NAMESPACE::Application;
@@ -34,7 +37,7 @@ START_NAMESPACE_DISTRHO
 
 extern double      d_lastUiSampleRate;
 extern void*       d_lastUiDspPtr;
-#ifdef HAVE_DGL
+#if !DISTRHO_PLUGIN_HAS_EXTERNAL_UI
 extern Window*     d_lastUiWindow;
 #endif
 extern uintptr_t   g_nextWindowId;
@@ -146,7 +149,20 @@ struct UI::PrivateData {
 // -----------------------------------------------------------------------
 // Plugin Window, needed to take care of resize properly
 
-#ifdef HAVE_DGL
+#if DISTRHO_PLUGIN_HAS_EXTERNAL_UI
+static inline
+UI* createUiWrapper(void* const dspPtr, const uintptr_t winId, const char* const bundlePath)
+{
+    d_lastUiDspPtr   = dspPtr;
+    g_nextWindowId   = winId;
+    g_nextBundlePath = bundlePath;
+    UI* const ret    = createUI();
+    d_lastUiDspPtr   = nullptr;
+    g_nextWindowId   = 0;
+    g_nextBundlePath = nullptr;
+    return ret;
+}
+#else // DISTRHO_PLUGIN_HAS_EXTERNAL_UI
 static inline
 UI* createUiWrapper(void* const dspPtr, Window* const window)
 {
@@ -212,7 +228,7 @@ protected:
         fIsReady = true;
     }
 
-#ifndef DGL_FILE_BROWSER_DISABLED
+# ifndef DGL_FILE_BROWSER_DISABLED
     // custom file-browser selected
     void fileBrowserSelected(const char* filename) override
     {
@@ -220,26 +236,13 @@ protected:
 
         fUI->uiFileBrowserSelected(filename);
     }
-#endif
+# endif
 
 private:
     UI* const fUI;
     bool fIsReady;
 };
-#else
-static inline
-UI* createUiWrapper(void* const dspPtr, const uintptr_t winId, const char* const bundlePath)
-{
-    d_lastUiDspPtr   = dspPtr;
-    g_nextWindowId   = winId;
-    g_nextBundlePath = bundlePath;
-    UI* const ret    = createUI();
-    d_lastUiDspPtr   = nullptr;
-    g_nextWindowId   = 0;
-    g_nextBundlePath = nullptr;
-    return ret;
-}
-#endif
+#endif // DISTRHO_PLUGIN_HAS_EXTERNAL_UI
 
 // -----------------------------------------------------------------------
 // UI exporter class
@@ -256,13 +259,13 @@ public:
                const setSizeFunc setSizeCall,
                void* const dspPtr = nullptr,
                const char* const bundlePath = nullptr)
-#ifdef HAVE_DGL
+#if DISTRHO_PLUGIN_HAS_EXTERNAL_UI
+        : fUI(createUiWrapper(dspPtr, winId, bundlePath)),
+#else
         : glApp(),
           glWindow(glApp, winId, dspPtr),
           fChangingSize(false),
           fUI(glWindow.getUI()),
-#else
-        : fUI(createUiWrapper(dspPtr, winId, bundlePath)),
 #endif
           fData((fUI != nullptr) ? fUI->pData : nullptr)
     {
@@ -276,54 +279,65 @@ public:
         fData->sendNoteCallbackFunc  = sendNoteCall;
         fData->setSizeCallbackFunc   = setSizeCall;
 
-#ifdef HAVE_DGL
+#if !DISTRHO_PLUGIN_HAS_EXTERNAL_UI
         // unused
         return; (void)bundlePath;
 #endif
     }
 
+#if DISTRHO_PLUGIN_HAS_EXTERNAL_UI
+    ~UIExporter()
+    {
+        delete fUI;
+    }
+#endif
+
     // -------------------------------------------------------------------
 
+#if DISTRHO_PLUGIN_HAS_EXTERNAL_UI
     uint getWidth() const noexcept
     {
-#ifdef HAVE_DGL
-        return glWindow.getWidth();
-#else
         DISTRHO_SAFE_ASSERT_RETURN(fUI != nullptr, 1);
         return fUI->getWidth();
-#endif
     }
 
     uint getHeight() const noexcept
     {
-#ifdef HAVE_DGL
-        return glWindow.getHeight();
-#else
         DISTRHO_SAFE_ASSERT_RETURN(fUI != nullptr, 1);
         return fUI->getHeight();
-#endif
     }
 
     bool isVisible() const noexcept
     {
-#ifdef HAVE_DGL
-        return glWindow.isVisible();
-#else
         DISTRHO_SAFE_ASSERT_RETURN(fUI != nullptr, false);
         return fUI->isRunning();
-#endif
     }
 
-    // -------------------------------------------------------------------
+    intptr_t getWindowId() const noexcept
+    {
+        return 0;
+    }
+#else
+    uint getWidth() const noexcept
+    {
+        return glWindow.getWidth();
+    }
+
+    uint getHeight() const noexcept
+    {
+        return glWindow.getHeight();
+    }
+
+    bool isVisible() const noexcept
+    {
+        return glWindow.isVisible();
+    }
 
     intptr_t getWindowId() const noexcept
     {
-#ifdef HAVE_DGL
         return glWindow.getWindowId();
-#else
-        return 0;
-#endif
     }
+#endif
 
     // -------------------------------------------------------------------
 
@@ -365,7 +379,39 @@ public:
 
     // -------------------------------------------------------------------
 
-#ifdef HAVE_DGL
+#if DISTRHO_PLUGIN_HAS_EXTERNAL_UI
+    void exec(IdleCallback* const cb)
+    {
+        DISTRHO_SAFE_ASSERT_RETURN(cb != nullptr,);
+        DISTRHO_SAFE_ASSERT_RETURN(fUI != nullptr,);
+
+        fUI->setVisible(true);
+        cb->idleCallback();
+
+        while (fUI->isRunning())
+        {
+            d_msleep(10);
+            cb->idleCallback();
+        }
+    }
+
+    void exec_idle()
+    {
+    }
+
+    bool idle()
+    {
+        return true;
+    }
+
+    void quit()
+    {
+        DISTRHO_SAFE_ASSERT_RETURN(fUI != nullptr,);
+
+        fUI->setVisible(false);
+        fUI->terminateAndWaitForProcess();
+    }
+#else
     void exec(IdleCallback* const cb)
     {
         DISTRHO_SAFE_ASSERT_RETURN(cb != nullptr,);
@@ -381,48 +427,64 @@ public:
         if (glWindow.isReady())
             fUI->uiIdle();
     }
-#endif
 
     bool idle()
     {
         DISTRHO_SAFE_ASSERT_RETURN(fUI != nullptr, false);
 
-#ifdef HAVE_DGL
         glApp.idle();
 
         if (glWindow.isReady())
             fUI->uiIdle();
 
         return ! glApp.isQuiting();
-#else
-        return fUI->isRunning();
-#endif
     }
 
     void quit()
     {
-#ifdef HAVE_DGL
         glWindow.close();
         glApp.quit();
-#else
-        DISTRHO_SAFE_ASSERT_RETURN(fUI != nullptr,);
-        fUI->terminateAndWaitForProcess();
-#endif
     }
 
+#endif
     // -------------------------------------------------------------------
 
+#if DISTRHO_PLUGIN_HAS_EXTERNAL_UI
     void setWindowTitle(const char* const uiTitle)
     {
-#ifdef HAVE_DGL
-        glWindow.setTitle(uiTitle);
-#else
         DISTRHO_SAFE_ASSERT_RETURN(fUI != nullptr,);
+
         fUI->setTitle(uiTitle);
-#endif
     }
 
-#ifdef HAVE_DGL
+    void setWindowSize(const uint width, const uint height, const bool = false)
+    {
+        DISTRHO_SAFE_ASSERT_RETURN(fUI != nullptr,);
+
+        fUI->setSize(width, height);
+    }
+
+    void setWindowTransientWinId(const uintptr_t winId)
+    {
+        DISTRHO_SAFE_ASSERT_RETURN(fUI != nullptr,);
+
+        fUI->setTransientWinId(winId);
+    }
+
+    bool setWindowVisible(const bool yesNo)
+    {
+        DISTRHO_SAFE_ASSERT_RETURN(fUI != nullptr, false);
+
+        fUI->setVisible(yesNo);
+
+        return fUI->isRunning();
+    }
+#else
+    void setWindowTitle(const char* const uiTitle)
+    {
+        glWindow.setTitle(uiTitle);
+    }
+
     void setWindowSize(const uint width, const uint height, const bool updateUI = false)
     {
         DISTRHO_SAFE_ASSERT_RETURN(fUI != nullptr,);
@@ -459,10 +521,6 @@ public:
     {
         return glWindow.handlePluginSpecial(press, key);
     }
-#else
-    void setWindowSize(const uint, const uint, const bool = false) {}
-    void setWindowTransientWinId(const uintptr_t) {}
-    bool setWindowVisible(const bool) { return true; }
 #endif
 
     // -------------------------------------------------------------------
@@ -483,7 +541,7 @@ public:
     }
 
 private:
-#ifdef HAVE_DGL
+#if !DISTRHO_PLUGIN_HAS_EXTERNAL_UI
     // -------------------------------------------------------------------
     // DGL Application and Window for this widget
 
diff --git a/examples/ExternalUI/DistrhoPluginInfo.h b/examples/ExternalUI/DistrhoPluginInfo.h
new file mode 100644
index 00000000..3163c2c3
--- /dev/null
+++ b/examples/ExternalUI/DistrhoPluginInfo.h
@@ -0,0 +1,36 @@
+/*
+ * DISTRHO Plugin Framework (DPF)
+ * Copyright (C) 2012-2018 Filipe Coelho <falktx@falktx.com>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any purpose with
+ * or without fee is hereby granted, provided that the above copyright notice and this
+ * permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD
+ * TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN
+ * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+ * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
+ * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef DISTRHO_PLUGIN_INFO_H_INCLUDED
+#define DISTRHO_PLUGIN_INFO_H_INCLUDED
+
+#define DISTRHO_PLUGIN_BRAND "DISTRHO"
+#define DISTRHO_PLUGIN_NAME  "ExternalUI"
+#define DISTRHO_PLUGIN_URI   "http://distrho.sf.net/examples/ExternalUI"
+
+#define DISTRHO_PLUGIN_HAS_UI          1
+#define DISTRHO_PLUGIN_HAS_EMBED_UI    0
+#define DISTRHO_PLUGIN_HAS_EXTERNAL_UI 1
+#define DISTRHO_PLUGIN_IS_RT_SAFE      1
+#define DISTRHO_PLUGIN_NUM_INPUTS      1
+#define DISTRHO_PLUGIN_NUM_OUTPUTS     1
+
+enum Parameters {
+    kParameterLevel = 0,
+    kParameterCount
+};
+
+#endif // DISTRHO_PLUGIN_INFO_H_INCLUDED
diff --git a/examples/ExternalUI/ExternalExamplePlugin.cpp b/examples/ExternalUI/ExternalExamplePlugin.cpp
new file mode 100644
index 00000000..dbecdcc6
--- /dev/null
+++ b/examples/ExternalUI/ExternalExamplePlugin.cpp
@@ -0,0 +1,188 @@
+/*

+ * DISTRHO Plugin Framework (DPF)

+ * Copyright (C) 2012-2018 Filipe Coelho <falktx@falktx.com>

+ *

+ * Permission to use, copy, modify, and/or distribute this software for any purpose with

+ * or without fee is hereby granted, provided that the above copyright notice and this

+ * permission notice appear in all copies.

+ *

+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD

+ * TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN

+ * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL

+ * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER

+ * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN

+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

+ */

+

+#include "DistrhoPlugin.hpp"

+

+START_NAMESPACE_DISTRHO

+

+// -----------------------------------------------------------------------------------------------------------

+

+/**

+  Plugin to show how to get some basic information sent to the UI.

+ */

+class ExternalExamplePlugin : public Plugin

+{

+public:

+    ExternalExamplePlugin()

+        : Plugin(kParameterCount, 0, 0),

+          fValue(0.0f)

+    {

+    }

+

+protected:

+   /* --------------------------------------------------------------------------------------------------------

+    * Information */

+

+   /**

+      Get the plugin label.

+      This label is a short restricted name consisting of only _, a-z, A-Z and 0-9 characters.

+    */

+    const char* getLabel() const override

+    {

+        return "ExternalUI";

+    }

+

+   /**

+      Get an extensive comment/description about the plugin.

+    */

+    const char* getDescription() const override

+    {

+        return "Plugin to show how to use an external / remote UI.";

+    }

+

+   /**

+      Get the plugin author/maker.

+    */

+    const char* getMaker() const override

+    {

+        return "DISTRHO";

+    }

+

+   /**

+      Get the plugin homepage.

+    */

+    const char* getHomePage() const override

+    {

+        return "https://github.com/DISTRHO/DPF";

+    }

+

+   /**

+      Get the plugin license name (a single line of text).

+      For commercial plugins this should return some short copyright information.

+    */

+    const char* getLicense() const override

+    {

+        return "ISC";

+    }

+

+   /**

+      Get the plugin version, in hexadecimal.

+    */

+    uint32_t getVersion() const override

+    {

+        return d_version(1, 0, 0);

+    }

+

+   /**

+      Get the plugin unique Id.

+      This value is used by LADSPA, DSSI and VST plugin formats.

+    */

+    int64_t getUniqueId() const override

+    {

+        return d_cconst('d', 'E', 'x', 't');

+    }

+

+   /* --------------------------------------------------------------------------------------------------------

+    * Init */

+

+   /**

+      Initialize the parameter @a index.

+      This function will be called once, shortly after the plugin is created.

+    */

+    void initParameter(uint32_t index, Parameter& parameter) override

+    {

+        if (index != 0)

+            return;

+

+        parameter.hints      = kParameterIsAutomable|kParameterIsInteger;

+        parameter.ranges.def = 0.0f;

+        parameter.ranges.min = 0.0f;

+        parameter.ranges.max = 100.0f;

+        parameter.name   = "Value";

+        parameter.symbol = "value";

+    }

+

+   /* --------------------------------------------------------------------------------------------------------

+    * Internal data */

+

+   /**

+      Get the current value of a parameter.

+      The host may call this function from any context, including realtime processing.

+    */

+    float getParameterValue(uint32_t index) const override

+    {

+        if (index != 0)

+            return 0.0f;

+

+        return fValue;

+

+    }

+

+   /**

+      Change a parameter value.

+      The host may call this function from any context, including realtime processing.

+      When a parameter is marked as automable, you must ensure no non-realtime operations are performed.

+      @note This function will only be called for parameter inputs.

+    */

+    void setParameterValue(uint32_t index, float value) override

+    {

+        if (index != 0)

+            return;

+

+        fValue = value;

+    }

+

+   /* --------------------------------------------------------------------------------------------------------

+    * Audio/MIDI Processing */

+

+   /**

+      Run/process function for plugins without MIDI input.

+      @note Some parameters might be null if there are no audio inputs or outputs.

+    */

+    void run(const float** inputs, float** outputs, uint32_t frames) override

+    {

+       /**

+          This plugin does nothing, it just demonstrates information usage.

+          So here we directly copy inputs over outputs, leaving the audio untouched.

+          We need to be careful in case the host re-uses the same buffer for both ins and outs.

+        */

+        if (outputs[0] != inputs[0])

+            std::memcpy(outputs[0], inputs[0], sizeof(float)*frames);

+    }

+

+    // -------------------------------------------------------------------------------------------------------

+

+private:

+    // Parameters

+    float fValue;

+

+   /**

+      Set our plugin class as non-copyable and add a leak detector just in case.

+    */

+    DISTRHO_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR(ExternalExamplePlugin)

+};

+

+/* ------------------------------------------------------------------------------------------------------------

+ * Plugin entry point, called by DPF to create a new plugin instance. */

+

+Plugin* createPlugin()

+{

+    return new ExternalExamplePlugin();

+}

+

+// -----------------------------------------------------------------------------------------------------------

+

+END_NAMESPACE_DISTRHO

diff --git a/examples/ExternalUI/ExternalExampleUI.cpp b/examples/ExternalUI/ExternalExampleUI.cpp
new file mode 100644
index 00000000..66cfc85b
--- /dev/null
+++ b/examples/ExternalUI/ExternalExampleUI.cpp
@@ -0,0 +1,187 @@
+/*
+ * DISTRHO Plugin Framework (DPF)
+ * Copyright (C) 2012-2018 Filipe Coelho <falktx@falktx.com>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any purpose with
+ * or without fee is hereby granted, provided that the above copyright notice and this
+ * permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD
+ * TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN
+ * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+ * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
+ * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "DistrhoUI.hpp"
+
+// Extra includes for current path and fifo stuff
+#include <dlfcn.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+START_NAMESPACE_DISTRHO
+
+// TODO: generate a random, not-yet-existing, filename
+const char* const kFifoFilename = "/tmp/dpf-fifo-test";
+
+// Helper to get current path of this plugin
+static const char* getCurrentPluginFilename()
+{
+    Dl_info exeInfo;
+    void* localSymbol = (void*)kFifoFilename;
+    dladdr(localSymbol, &exeInfo);
+    return exeInfo.dli_fname;
+}
+
+// Helper to check if a file exists
+static bool fileExists(const char* const filename)
+{
+    return access(filename, F_OK) != -1;
+}
+
+// Helper function to keep trying to write until it succeeds or really errors out
+static ssize_t
+writeRetry(int fd, const void* src, size_t size)
+{
+	ssize_t error;
+
+	do {
+		error = write(fd, src, size);
+	} while (error == -1 && (errno == EINTR || errno == EPIPE));
+
+	return error;
+}
+
+// -----------------------------------------------------------------------------------------------------------
+
+class ExternalExampleUI : public UI
+{
+public:
+    ExternalExampleUI()
+        : UI(405, 256, true),
+          fFifo(-1),
+          fValue(0.0f),
+          fExternalScript(getNextBundlePath())
+    {
+        if (fExternalScript.isEmpty())
+        {
+            fExternalScript = getCurrentPluginFilename();
+            fExternalScript.truncate(fExternalScript.rfind('/'));
+        }
+
+        fExternalScript += "/d_extui.sh";
+        d_stdout("External script = %s", fExternalScript.buffer());
+    }
+
+protected:
+   /* --------------------------------------------------------------------------------------------------------
+    * DSP/Plugin Callbacks */
+
+   /**
+      A parameter has changed on the plugin side.
+      This is called by the host to inform the UI about parameter changes.
+    */
+    void parameterChanged(uint32_t index, float value) override
+    {
+        if (index != 0)
+            return;
+
+        fValue = value;
+
+        if (fFifo == -1)
+            return;
+
+        // NOTE: This is a terrible way to pass values, also locale might get in the way...
+        char valueStr[24];
+        std::memset(valueStr, 0, sizeof(valueStr));
+        std::snprintf(valueStr, 23, "%i\n", static_cast<int>(value + 0.5f));
+
+        DISTRHO_SAFE_ASSERT(writeRetry(fFifo, valueStr, 24) == sizeof(valueStr));
+    }
+
+   /* --------------------------------------------------------------------------------------------------------
+    * External Window overrides */
+
+   /**
+      Manage external process and IPC when UI is requested to be visible.
+    */
+    void setVisible(const bool yesNo) override
+    {
+        if (yesNo)
+        {
+            DISTRHO_SAFE_ASSERT_RETURN(fileExists(fExternalScript),);
+
+            mkfifo(kFifoFilename, 0666);
+            sync();
+
+            char winIdStr[24];
+            std::memset(winIdStr, 0, sizeof(winIdStr));
+            std::snprintf(winIdStr, 23, "%lu", getTransientWinId());
+
+            const char* args[] = {
+                fExternalScript.buffer(),
+                kFifoFilename,
+                "--progressbar", "External UI example",
+                "--title", getTitle(),
+                nullptr,
+            };
+            DISTRHO_SAFE_ASSERT_RETURN(startExternalProcess(args),);
+
+            // NOTE: this can lockup the current thread if the other side does not read the file!
+            fFifo = open(kFifoFilename, O_WRONLY);
+            DISTRHO_SAFE_ASSERT_RETURN(fFifo != -1,);
+
+            parameterChanged(0, fValue);
+        }
+        else
+        {
+            if (fFifo != -1)
+            {
+                if (isRunning())
+                {
+                    DISTRHO_SAFE_ASSERT(writeRetry(fFifo, "quit\n", 5) == 5);
+                    fsync(fFifo);
+                }
+                close(fFifo);
+                fFifo = -1;
+            }
+
+            unlink(kFifoFilename);
+            terminateAndWaitForProcess();
+        }
+
+        UI::setVisible(yesNo);
+    }
+
+    // -------------------------------------------------------------------------------------------------------
+
+private:
+    // IPC Stuff
+    int fFifo;
+
+    // Current value, cached for when UI becomes visible
+    float fValue;
+
+    // Path to external ui script
+    String fExternalScript;
+
+   /**
+      Set our UI class as non-copyable and add a leak detector just in case.
+    */
+    DISTRHO_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR(ExternalExampleUI)
+};
+
+/* ------------------------------------------------------------------------------------------------------------
+ * UI entry point, called by DPF to create a new UI instance. */
+
+UI* createUI()
+{
+    return new ExternalExampleUI();
+}
+
+// -----------------------------------------------------------------------------------------------------------
+
+END_NAMESPACE_DISTRHO
diff --git a/examples/ExternalUI/ExternalLauncher.sh b/examples/ExternalUI/ExternalLauncher.sh
new file mode 100755
index 00000000..1ca7c94c
--- /dev/null
+++ b/examples/ExternalUI/ExternalLauncher.sh
@@ -0,0 +1,40 @@
+#!/bin/bash
+
+# Read FIFO argument from CLI
+FIFO=${1}
+shift
+
+if [ ! -e "${FIFO}" ]; then
+  echo "Fifo file ${FIFO} does not exist, cannot run"
+  exit 1
+fi
+
+# Start kdialog with all other arguments and get dbus reference
+dbusRef=$(kdialog "$@" 100)
+
+if [ $? -ne 0 ] || [ -z "${dbusRef}" ]; then
+  echo "Failed to start kdialog"
+  exit 1
+fi
+
+# Setup cancellation point for this script
+quitfn() {
+    qdbus ${dbusRef} close 2>/dev/null
+}
+
+trap quitfn SIGINT
+trap quitfn SIGTERM
+
+# Read Fifo for new values or a quit message
+while read line <"${FIFO}"; do
+  if echo "${line}" | grep -q "quit"; then
+    break
+  fi
+  if ! qdbus ${dbusRef} Set "" value "${line}"; then
+    break
+  fi
+done
+
+# Cleanup
+rm -f "${FIFO}"
+quitfn
diff --git a/examples/ExternalUI/Makefile b/examples/ExternalUI/Makefile
new file mode 100644
index 00000000..ba1df228
--- /dev/null
+++ b/examples/ExternalUI/Makefile
@@ -0,0 +1,40 @@
+#!/usr/bin/make -f
+# Makefile for DISTRHO Plugins #
+# ---------------------------- #
+# Created by falkTX
+#
+
+# --------------------------------------------------------------
+# Project name, used for binaries
+
+NAME = d_extui
+
+# --------------------------------------------------------------
+# Files to build
+
+FILES_DSP = \
+	ExternalExamplePlugin.cpp
+
+FILES_UI  = \
+	ExternalExampleUI.cpp
+
+# --------------------------------------------------------------
+# Do some magic
+
+include ../../Makefile.plugins.mk
+
+LINK_FLAGS += -ldl
+
+# --------------------------------------------------------------
+# Enable all possible plugin types
+
+ifeq ($(HAVE_JACK),true)
+TARGETS += jack
+endif
+
+TARGETS += dssi
+TARGETS += lv2_sep
+
+all: $(TARGETS)
+
+# --------------------------------------------------------------
diff --git a/examples/ExternalUI/README.md b/examples/ExternalUI/README.md
new file mode 100644
index 00000000..6fb4d3ea
--- /dev/null
+++ b/examples/ExternalUI/README.md
@@ -0,0 +1,11 @@
+# External UI example
+
+This example will show how to use an external / remote UI together with DPF.<br/>
+
+The Plugin has a shell script that calls kdialog and uses qdbus for sending values to it.<br/>
+It is a very ugly way to show a remote UI (using a shell script!), but it is only to prove the point.<br/>
+
+Note that everything regarding external UIs is still a bit experimental in DPF.<br/>
+There is Unix-specific code in there.<br/>
+
+If this is something you are interested on using and contributing to, please let us know.<br/>