[glass] Add NetworkTables Log window (#2997)

This moves NetworkTable log messages out of the console (which is hidden on some platforms).

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

@@ -16,6 +16,7 @@
 #include "glass/View.h"
 #include "glass/networktables/NetworkTables.h"
 #include "glass/networktables/NetworkTablesProvider.h"
+#include "glass/other/Log.h"
 #include "glass/other/Plot.h"
 
 namespace gui = wpi::gui;
@@ -35,8 +36,10 @@ static std::unique_ptr<glass::NetworkTablesProvider> gNtProvider;
 
 static std::unique_ptr<glass::NetworkTablesModel> gNetworkTablesModel;
 static std::unique_ptr<NetworkTablesSettings> gNetworkTablesSettings;
+static glass::LogData gNetworkTablesLog;
 static glass::Window* gNetworkTablesWindow;
 static glass::Window* gNetworkTablesSettingsWindow;
+static glass::Window* gNetworkTablesLogWindow;
 
 static void NtInitialize() {
   // update window title when connection status changes
@@ -62,6 +65,36 @@ static void NtInitialize() {
     }
   });
 
+  // handle NetworkTables log messages
+  auto logPoller = nt::CreateLoggerPoller(inst);
+  nt::AddPolledLogger(logPoller, NT_LOG_INFO, 100);
+  gui::AddEarlyExecute([logPoller] {
+    bool timedOut;
+    for (auto&& msg : nt::PollLogger(logPoller, 0, &timedOut)) {
+      const char* level = "";
+      if (msg.level >= NT_LOG_CRITICAL) {
+        level = "CRITICAL: ";
+      } else if (msg.level >= NT_LOG_ERROR) {
+        level = "ERROR: ";
+      } else if (msg.level >= NT_LOG_WARNING) {
+        level = "WARNING: ";
+      }
+      gNetworkTablesLog.Append(
+          wpi::Twine{level} + msg.message + wpi::Twine{" ("} + msg.filename +
+          wpi::Twine{':'} + wpi::Twine{msg.line} + wpi::Twine{")\n"});
+    }
+  });
+
+  gNetworkTablesLogWindow = gNtProvider->AddWindow(
+      "NetworkTables Log",
+      std::make_unique<glass::LogView>(&gNetworkTablesLog));
+  if (gNetworkTablesLogWindow) {
+    gNetworkTablesLogWindow->SetDefaultPos(250, 615);
+    gNetworkTablesLogWindow->SetDefaultSize(600, 130);
+    gNetworkTablesLogWindow->SetVisible(false);
+    gNetworkTablesLogWindow->DisableRenamePopup();
+  }
+
   // NetworkTables table window
   gNetworkTablesModel = std::make_unique<glass::NetworkTablesModel>();
   gui::AddEarlyExecute([] { gNetworkTablesModel->Update(); });
@@ -132,6 +165,9 @@ int main() {
       if (gNetworkTablesWindow) {
         gNetworkTablesWindow->DisplayMenuItem("NetworkTables View");
       }
+      if (gNetworkTablesLogWindow) {
+        gNetworkTablesLogWindow->DisplayMenuItem("NetworkTables Log");
+      }
       ImGui::Separator();
       gNtProvider->DisplayMenu();
       ImGui::EndMenu();

glass/src/lib/native/cpp/other/Log.cpp

@@ -0,0 +1,70 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+#include "glass/other/Log.h"
+
+#include <imgui.h>
+#include <wpi/raw_ostream.h>
+
+using namespace glass;
+
+void LogData::Clear() {
+  m_buf.clear();
+  m_lineOffsets.clear();
+  m_lineOffsets.push_back(0);
+}
+
+void LogData::Append(const wpi::Twine& msg) {
+  if (m_lineOffsets.size() >= m_maxLines) {
+    Clear();
+  }
+
+  size_t oldSize = m_buf.size();
+  wpi::raw_vector_ostream os{m_buf};
+  msg.print(os);
+  for (size_t newSize = m_buf.size(); oldSize < newSize; ++oldSize) {
+    if (m_buf[oldSize] == '\n') {
+      m_lineOffsets.push_back(oldSize + 1);
+    }
+  }
+}
+
+void glass::DisplayLog(LogData* data, bool autoScroll) {
+  if (data->m_buf.empty()) {
+    return;
+  }
+  ImGui::PushStyleVar(ImGuiStyleVar_ItemSpacing, ImVec2(0, 0));
+  const char* buf = data->m_buf.data();
+  const char* bufEnd = buf + data->m_buf.size();
+  ImGuiListClipper clipper;
+  clipper.Begin(data->m_lineOffsets.size());
+  while (clipper.Step()) {
+    for (size_t lineNum = clipper.DisplayStart;
+         lineNum < static_cast<size_t>(clipper.DisplayEnd); lineNum++) {
+      const char* lineStart = buf + data->m_lineOffsets[lineNum];
+      const char* lineEnd = (lineNum + 1 < data->m_lineOffsets.size())
+                                ? (buf + data->m_lineOffsets[lineNum + 1] - 1)
+                                : bufEnd;
+      ImGui::TextUnformatted(lineStart, lineEnd);
+    }
+  }
+  clipper.End();
+  ImGui::PopStyleVar();
+
+  if (autoScroll && ImGui::GetScrollY() >= ImGui::GetScrollMaxY()) {
+    ImGui::SetScrollHereY(1.0f);
+  }
+}
+
+void LogView::Display() {
+  if (ImGui::BeginPopupContextItem()) {
+    ImGui::Checkbox("Auto-scroll", &m_autoScroll);
+    if (ImGui::Selectable("Clear")) {
+      m_data->Clear();
+    }
+    ImGui::EndPopup();
+  }
+
+  DisplayLog(m_data, m_autoScroll);
+}

glass/src/lib/native/include/glass/other/Log.h

@@ -0,0 +1,43 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+#pragma once
+
+#include <vector>
+
+#include <wpi/Twine.h>
+
+#include "glass/View.h"
+
+namespace glass {
+
+class LogData {
+  friend void DisplayLog(LogData*, bool);
+
+ public:
+  explicit LogData(size_t maxLines = 10000) : m_maxLines{maxLines} {}
+
+  void Clear();
+  void Append(const wpi::Twine& msg);
+
+ private:
+  size_t m_maxLines;
+  std::vector<char> m_buf;
+  std::vector<size_t> m_lineOffsets{0};
+};
+
+void DisplayLog(LogData* data, bool autoScroll);
+
+class LogView : public View {
+ public:
+  explicit LogView(LogData* data) : m_data{data} {}
+
+  void Display() override;
+
+ private:
+  LogData* m_data;
+  bool m_autoScroll{true};
+};
+
+}  // namespace glass