[glass] Add glass: an application for display of robot data

This reuses many pieces of the current simulation GUI.  The common pieces have
been refactored into the libglass library.

The libglass library is designed to be usable for other standalone data
visualization applications (e.g. viewing data logs).

The name "glass" comes from "glass cockpit", as the application features
several multi-function displays that can be adjusted to display robot
information as needed.

glass/src/app/native/cpp/NetworkTablesSettings.cpp

@@ -0,0 +1,71 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) 2020 FIRST. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#include "NetworkTablesSettings.h"
+
+#include <utility>
+
+#include <imgui.h>
+#include <imgui_stdlib.h>
+#include <ntcore_cpp.h>
+#include <wpi/SmallVector.h>
+#include <wpi/StringRef.h>
+#include <wpi/raw_ostream.h>
+
+#include "glass/Context.h"
+
+NetworkTablesSettings::NetworkTablesSettings(NT_Inst inst,
+                                             const char* storageName)
+    : m_inst{inst} {
+  auto& storage = glass::GetStorage(storageName);
+  m_pMode = storage.GetIntRef("mode");
+  m_pIniName = storage.GetStringRef("iniName", "networktables.ini");
+  m_pServerTeam = storage.GetStringRef("serverTeam");
+  m_pListenAddress = storage.GetStringRef("listenAddress");
+}
+
+void NetworkTablesSettings::Update() {
+  if (!m_restart) return;
+  m_restart = false;
+  nt::StopClient(m_inst);
+  nt::StopServer(m_inst);
+  nt::StopLocal(m_inst);
+  if (*m_pMode == 1) {
+    wpi::StringRef serverTeam{*m_pServerTeam};
+    unsigned int team;
+    if (!serverTeam.contains('.') && !serverTeam.getAsInteger(10, team)) {
+      nt::StartClientTeam(m_inst, team, NT_DEFAULT_PORT);
+    } else {
+      wpi::SmallVector<wpi::StringRef, 4> serverNames;
+      wpi::SmallVector<std::pair<wpi::StringRef, unsigned int>, 4> servers;
+      serverTeam.split(serverNames, ',', -1, false);
+      for (auto&& serverName : serverNames)
+        servers.emplace_back(serverName, NT_DEFAULT_PORT);
+      nt::StartClient(m_inst, servers);
+    }
+  } else if (*m_pMode == 2) {
+    nt::StartServer(m_inst, m_pIniName->c_str(), m_pListenAddress->c_str(),
+                    NT_DEFAULT_PORT);
+  }
+}
+
+void NetworkTablesSettings::Display() {
+  static const char* modeOptions[] = {"Disabled", "Client", "Server"};
+  ImGui::Combo("Mode", m_pMode, modeOptions, 3);
+  switch (*m_pMode) {
+    case 1:
+      ImGui::InputText("Team/IP", m_pServerTeam);
+      break;
+    case 2:
+      ImGui::InputText("Listen Address", m_pListenAddress);
+      ImGui::InputText("ini Filename", m_pIniName);
+      break;
+    default:
+      break;
+  }
+  if (ImGui::Button("Apply")) m_restart = true;
+}

glass/src/app/native/cpp/NetworkTablesSettings.h

@@ -0,0 +1,35 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) 2020 FIRST. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#pragma once
+
+#include <string>
+
+#include <ntcore_cpp.h>
+
+namespace wpi {
+template <typename T>
+class SmallVectorImpl;
+}  // namespace wpi
+
+class NetworkTablesSettings {
+ public:
+  explicit NetworkTablesSettings(
+      NT_Inst inst = nt::GetDefaultInstance(),
+      const char* storageName = "NetworkTables Settings");
+
+  void Update();
+  void Display();
+
+ private:
+  NT_Inst m_inst;
+  bool m_restart = true;
+  int* m_pMode;
+  std::string* m_pIniName;
+  std::string* m_pServerTeam;
+  std::string* m_pListenAddress;
+};

glass/src/app/native/cpp/main.cpp

@@ -0,0 +1,137 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) 2020 FIRST. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#include <memory>
+
+#include <GLFW/glfw3.h>
+#include <imgui.h>
+#include <ntcore_cpp.h>
+#include <wpi/SmallString.h>
+#include <wpigui.h>
+
+#include "NetworkTablesSettings.h"
+#include "glass/Context.h"
+#include "glass/Model.h"
+#include "glass/View.h"
+#include "glass/networktables/NetworkTables.h"
+#include "glass/networktables/NetworkTablesProvider.h"
+#include "glass/other/Plot.h"
+
+namespace gui = wpi::gui;
+
+static std::unique_ptr<glass::PlotProvider> gPlotProvider;
+static std::unique_ptr<glass::NetworkTablesProvider> gNtProvider;
+
+static std::unique_ptr<glass::NetworkTablesModel> gNetworkTablesModel;
+static std::unique_ptr<NetworkTablesSettings> gNetworkTablesSettings;
+static glass::Window* gNetworkTablesWindow;
+static glass::Window* gNetworkTablesSettingsWindow;
+
+static void NtInitialize() {
+  // update window title when connection status changes
+  auto inst = nt::GetDefaultInstance();
+  auto poller = nt::CreateConnectionListenerPoller(inst);
+  nt::AddPolledConnectionListener(poller, true);
+  gui::AddEarlyExecute([poller] {
+    auto win = gui::GetSystemWindow();
+    if (!win) return;
+    bool timedOut;
+    for (auto&& event : nt::PollConnectionListener(poller, 0, &timedOut)) {
+      if (event.connected) {
+        wpi::SmallString<64> title;
+        title = "Glass - Connected (";
+        title += event.conn.remote_ip;
+        title += ')';
+        glfwSetWindowTitle(win, title.c_str());
+      } else {
+        glfwSetWindowTitle(win, "Glass - DISCONNECTED");
+      }
+    }
+  });
+
+  // NetworkTables table window
+  gNetworkTablesModel = std::make_unique<glass::NetworkTablesModel>();
+  gui::AddEarlyExecute([] { gNetworkTablesModel->Update(); });
+
+  gNetworkTablesWindow = gNtProvider->AddWindow(
+      "NetworkTables",
+      std::make_unique<glass::NetworkTablesView>(gNetworkTablesModel.get()));
+  if (gNetworkTablesWindow) {
+    gNetworkTablesWindow->SetDefaultPos(250, 277);
+    gNetworkTablesWindow->SetDefaultSize(750, 185);
+    gNetworkTablesWindow->DisableRenamePopup();
+  }
+
+  // NetworkTables settings window
+  gNetworkTablesSettings = std::make_unique<NetworkTablesSettings>();
+  gui::AddEarlyExecute([] { gNetworkTablesSettings->Update(); });
+
+  gNetworkTablesSettingsWindow = gNtProvider->AddWindow(
+      "NetworkTables Settings", [] { gNetworkTablesSettings->Display(); });
+  if (gNetworkTablesSettingsWindow) {
+    gNetworkTablesSettingsWindow->SetDefaultPos(30, 30);
+    gNetworkTablesSettingsWindow->SetFlags(ImGuiWindowFlags_AlwaysAutoResize);
+    gNetworkTablesSettingsWindow->DisableRenamePopup();
+  }
+}
+
+#ifdef _WIN32
+int __stdcall WinMain(void* hInstance, void* hPrevInstance, char* pCmdLine,
+                      int nCmdShow) {
+#else
+int main() {
+#endif
+  gui::CreateContext();
+  glass::CreateContext();
+
+  gPlotProvider = std::make_unique<glass::PlotProvider>("Plot");
+  gNtProvider = std::make_unique<glass::NetworkTablesProvider>("NTProvider");
+
+  gui::AddInit([] { ImGui::GetIO().IniFilename = "glass.ini"; });
+  gPlotProvider->GlobalInit();
+  gui::AddInit([] { gPlotProvider->ResetTime(); });
+  gNtProvider->GlobalInit();
+  gui::AddInit(NtInitialize);
+
+  glass::AddStandardNetworkTablesViews(*gNtProvider);
+
+  gui::AddLateExecute([] {
+    ImGui::BeginMainMenuBar();
+    gui::EmitViewMenu();
+    if (ImGui::BeginMenu("NetworkTables")) {
+      if (gNetworkTablesSettingsWindow)
+        gNetworkTablesSettingsWindow->DisplayMenuItem("NetworkTables Settings");
+      if (gNetworkTablesWindow)
+        gNetworkTablesWindow->DisplayMenuItem("NetworkTables View");
+      ImGui::Separator();
+      gNtProvider->DisplayMenu();
+      ImGui::EndMenu();
+    }
+    if (ImGui::BeginMenu("Plot")) {
+      bool paused = gPlotProvider->IsPaused();
+      if (ImGui::MenuItem("Pause All Plots", nullptr, &paused)) {
+        gPlotProvider->SetPaused(paused);
+      }
+      if (ImGui::MenuItem("Reset Plot Time")) gPlotProvider->ResetTime();
+      ImGui::Separator();
+      gPlotProvider->DisplayMenu();
+      ImGui::EndMenu();
+    }
+    ImGui::EndMainMenuBar();
+  });
+
+  gui::Initialize("Glass - DISCONNECTED", 1024, 768);
+  gui::Main();
+
+  gNetworkTablesModel.reset();
+  gNetworkTablesSettings.reset();
+  gNtProvider.reset();
+  gPlotProvider.reset();
+
+  glass::DestroyContext();
+  gui::DestroyContext();
+}