(WIP) UI: Implement Dear ImGui UI part

Author: AnClark

CMakeLists.txt

@@ -12,6 +12,7 @@ add_subdirectory (dpf)
 
 include_directories (   
     src/
+    dpf-widgets/opengl/
 )
 
 set (SRC_BACKEND
@@ -42,5 +43,7 @@ dpf_add_plugin (${PROJECT_NAME}
         src/CetoneUIHelper.cpp
         src/Images/CetoneArtwork.cpp
         src/Fonts/CetoneFonts.cpp
+        dpf-widgets/opengl/DearImGui.cpp
+        src/Widgets/ImGui_UI.cpp
 )
 

src/CetoneUI.cpp

@@ -107,6 +107,15 @@ CCetoneUI::CCetoneUI()
     _createSwitchButton(fBtnGlideState, pPortaMode, 764, 150);
 
     _createSwitchButton(fBtnLFOTrigger, pLfo1Trig, 677, 260);
+
+    /* ImGui instance (popup menus, subwindows, etc.) */
+    fImGuiInstance = new ImGuiUI(getTopLevelWidget(), this);
+
+    /* "About" button (by clicking the plugin logo) */
+    _createHiddenButton(fBtnAbout, BTN_ABOUT, Size<uint>(118, 25), Point<int>(0, 0));
+
+    /* Popup menu button on params which has constant value sets */
+    _createHiddenButton(fBtnOsc1Waveform, pOsc1Wave, Size<uint>(45, 10 + 2), Point<int>(10 + 48 * 2, 200 + 2));
 }
 
 void CCetoneUI::parameterChanged(uint32_t index, float value)
@@ -349,14 +358,24 @@ void CCetoneUI::parameterChanged(uint32_t index, float value)
 
 void CCetoneUI::imageButtonClicked(ImageButton* button, int)
 {
-#if 0
-    switch (button->getId()) {
-    case BTN_PANIC: {
-        panic();
-        break;
-    }
+    switch (button->getId())
+    {
+        case BTN_ABOUT:
+        {
+            if (fImGuiInstance)
+                fImGuiInstance->isAboutWindowOpen = !fImGuiInstance->isAboutWindowOpen;
+            break;
+        }
+        case pOsc1Wave:
+        {
+            if(fImGuiInstance)
+            {
+                fImGuiInstance->menuPos = ImVec2(fBtnOsc1Waveform->getAbsolutePos().getX(), fBtnOsc1Waveform->getAbsolutePos().getY() + fBtnOsc1Waveform->getHeight());
+                fImGuiInstance->requestMenuId = pOsc1Wave;
+            }
+            break;
+        }
     }
-#endif
 }
 
 void CCetoneUI::imageSwitchClicked(ImageSwitch* button, bool down)

src/CetoneUI.hpp

@@ -4,6 +4,8 @@
 #include "ImageWidgets.hpp"
 #include "NanoVG.hpp"
 
+#include "Widgets/ImGui_UI.hpp"
+
 using DGL_NAMESPACE::ImageAboutWindow;
 using DGL_NAMESPACE::ImageButton;
 using DGL_NAMESPACE::ImageKnob;
@@ -55,6 +57,12 @@ class CCetoneUI : public DISTRHO::UI,
     NanoVG fNanoText;
     char fLabelBuffer[32 + 1];
 
+    // -------------------------------------------------------------------
+    // Dear ImGui Instance
+
+    ScopedPointer<ImGuiUI> fImGuiInstance;
+    friend class ImGuiUI;
+
     // -------------------------------------------------------------------
     // Image resources
 
@@ -93,6 +101,13 @@ class CCetoneUI : public DISTRHO::UI,
     ScopedPointer<ImageSwitch> fBtnGlideState;
     ScopedPointer<ImageSwitch> fBtnLFOTrigger;
 
+    // -------------------------------------------------------------------
+    // Buttons
+
+    ScopedPointer<ImageButton> fBtnAbout;
+
+    ScopedPointer<ImageButton> fBtnOsc1Waveform;
+
     // -------------------------------------------------------------------
     // Helpers
 
@@ -127,5 +142,6 @@ class CCetoneUI : public DISTRHO::UI,
 // Button IDs
 
 constexpr uint BTN_PANIC = d_cconst('p', 'n', 'i', 'c');
+constexpr uint BTN_ABOUT = d_cconst('a', 'b', 't', '.');
 
 // -----------------------------------------------------------------------

src/Widgets/ImGui_UI.cpp

@@ -0,0 +1,82 @@
+#include "ImGui_UI.hpp"
+#include "DistrhoPluginInfo.h"
+
+#include "Structures.h"
+#include "Defines.h"
+
+#include "CetoneUI.hpp" // For class CCetoneUI
+
+void ImGuiUI::onImGuiDisplay()
+{
+    double scaleFactor = getScaleFactor() * userScaling;
+    const double initialSize = 800 * scaleFactor;
+
+    //
+    // "About" Window
+    //
+    {
+        ImGui::SetNextWindowPos(ImVec2(initialSize / 4, initialSize / 16), ImGuiCond_Once);
+        ImGui::SetNextWindowSize(ImVec2(600, 230), ImGuiCond_Once);
+
+        if (isAboutWindowOpen)
+        {
+            ImGui::Begin("About " DISTRHO_PLUGIN_NAME, &isAboutWindowOpen, ImGuiWindowFlags_NoCollapse | ImGuiWindowFlags_NoResize);
+            {
+                ImGui::SeparatorText(DISTRHO_PLUGIN_NAME);
+                ImGui::Text("Light-weight monophonic analogue-style synthesizer, by Neotec Software.\n");
+
+                ImGui::SeparatorText("Authors");
+                ImGui::BulletText("René 'Neotec' Jeschke - Original developer");
+                ImGui::BulletText("AnClark Liu <[email protected]> - Ported to DPF, Further developments");
+
+                ImGui::SeparatorText("License");
+                ImGui::BulletText("This project is licensed under GNU General Public License, version 3.");
+
+                ImGui::Text("\n\n");
+                ImGui::Dummy(ImVec2(490, 0));
+                ImGui::SameLine();
+                if (ImGui::Button("OK", ImVec2(80, 0)))
+                    isAboutWindowOpen = false;
+            }
+            ImGui::End(); 
+        }
+    }
+
+
+    // Specify menu position
+    ImGui::SetNextWindowPos(menuPos); // 指定屏幕坐标位置
+
+    // Here, variable `requestTestMenuOpen` acts as an "event flag" to request ImGui to show the menu.
+    //
+    // Dear ImGui has its own mechanism to show popup menus, which does not require a flag to control its exisitance.
+    // This is quite different from window (ImGui::Begin()).
+    // So just call this function once, your popup will stick on the screen unless you do some operations.
+    //
+    switch (requestMenuId)
+    {
+        case pOsc1Wave:
+            ImGui::OpenPopup("menu_osc1_wave");
+        
+        default:
+            requestMenuId = 0;        // Reset flag state after EACH menu popup
+    }
+
+    // Create popup menu
+    // [NOTICE] ImGui::BeginPopup() MUST be put after ImGui::OpenPopup(), otherwise popup won't show!
+    if (ImGui::BeginPopup("menu_osc1_wave"))
+    {
+        ImGui::SeparatorText("Waveform");
+        if (ImGui::MenuItem("Saw")) { _triggerParamUpdate(pOsc1Wave, ui->_pi2f(OWAVE_SAW, OWAVE_MAX)); }
+        if (ImGui::MenuItem("Pulse")) { _triggerParamUpdate(pOsc1Wave, ui->_pi2f(OWAVE_PULSE, OWAVE_MAX)); }
+        if (ImGui::MenuItem("Triangle")) { _triggerParamUpdate(pOsc1Wave, ui->_pi2f(OWAVE_TRI, OWAVE_MAX)); }
+        if (ImGui::MenuItem("Sine")) { _triggerParamUpdate(pOsc1Wave, ui->_pi2f(OWAVE_SINE, OWAVE_MAX)); }
+        if (ImGui::MenuItem("Noise")) { _triggerParamUpdate(pOsc1Wave, ui->_pi2f(OWAVE_C64NOISE, OWAVE_MAX)); }
+        ImGui::EndPopup();
+    }
+}
+
+void ImGuiUI::_triggerParamUpdate(uint32_t paramId, float newValue)
+{
+    ui->setParameterValue(paramId, newValue);   // Tell the DSP to update parameter value
+    ui->parameterChanged(paramId, newValue);    // Request UI refresh
+}

src/Widgets/ImGui_UI.hpp

@@ -0,0 +1,51 @@
+/*
+ * Inspector Window for DPF
+ * Copyright (C) 2022-2025 Filipe Coelho <[email protected]>
+ *
+ * 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.
+ */
+
+#pragma once
+
+#include "DearImGui.hpp"
+
+// Forward decls.
+class CCetoneUI;
+
+
+// --------------------------------------------------------------------------------------------------------------------
+
+class ImGuiUI : public ImGuiTopLevelWidget
+{
+
+public:
+    CCetoneUI *ui;
+
+    bool isAboutWindowOpen = false;
+    uint16_t requestMenuId = 0;
+    
+    ImVec2 menuPos{0, 0};
+
+    double userScaling = 1.0f;
+
+    ImGuiUI(TopLevelWidget* const tlw, CCetoneUI* const ui) : 
+        ImGuiTopLevelWidget(tlw->getWindow()),
+        ui(ui)
+        {
+        }
+
+protected:
+    void onImGuiDisplay() override;
+
+private:
+    void _triggerParamUpdate(uint32_t paramId, float newValue);
+};