engine/include/sophia/ui/debug_ui.hpp

@@ -18,12 +18,14 @@ class DebugUI {
 
   void showPanelRegistry(bool show = true);
   void showFrameStats(bool show = true);
+  void showConsole(bool show = true);
 
  private:
   PanelRegistry& registry;
 
   PanelHandle panelRegistryHandle;
   PanelHandle frameStatsHandle;
+  PanelHandle consoleHandle;
 };
 
 }  // namespace sophia

engine/src/ui/debug_ui.cpp

@@ -1,5 +1,6 @@
 #include <sophia/ui/debug_ui.hpp>
 
+#include "panels/console_panel.hpp"
 #include "panels/frame_stats_panel.hpp"
 #include "panels/panel_registry_panel.hpp"
 
@@ -9,17 +10,20 @@ DebugUI::DebugUI(PanelRegistry& registry) : registry{registry} {
   // #ifndef NDEBUG
   this->panelRegistryHandle = registry.emplace<PanelRegistryPanel>(registry);
   this->frameStatsHandle = registry.emplace<FrameStatsPanel>();
+  this->consoleHandle = registry.emplace<ConsolePanel>();
   // #endif  // !NDEBUG
 }
 
 void DebugUI::show() {
   showPanelRegistry(true);
   showFrameStats(true);
+  showConsole(true);
 }
 
 void DebugUI::hide() {
   showPanelRegistry(false);
   showFrameStats(false);
+  showConsole(false);
 }
 
 void DebugUI::showPanelRegistry(bool show) {
@@ -34,4 +38,10 @@ void DebugUI::showFrameStats(bool show) {
   }
 }
 
+void DebugUI::showConsole(bool show) {
+  if (registry.isValid(consoleHandle)) {
+    registry.get(consoleHandle).setVisible(show);
+  }
+}
+
 }  // namespace sophia

engine/src/ui/panels/console_panel.cpp

@@ -0,0 +1,136 @@
+#include "console_panel.hpp"
+
+#include <algorithm>
+
+namespace sophia {
+
+namespace {
+constexpr ImVec4 COLOR_DEFAULT = ImVec4(0.85f, 0.85f, 0.85f, 1.0f);
+constexpr ImVec4 COLOR_COMMAND = ImVec4(1.0f, 0.78f, 0.37f, 1.0f);
+constexpr ImVec4 COLOR_ERROR = ImVec4(1.0f, 0.4f, 0.4f, 1.0f);
+constexpr ImVec4 COLOR_INFO = ImVec4(0.4f, 0.7f, 1.0f, 1.0f);
+}  // namespace
+
+void ConsolePanel::registerDefaultCommands() {
+  log("Console ready. Type 'help' for a list of commands.");
+}
+
+void ConsolePanel::log(const std::string& message) {
+  entries.push_back(Entry{message, COLOR_DEFAULT});
+  scrollToBottom = true;
+}
+
+void ConsolePanel::clear() { entries.clear(); }
+
+void ConsolePanel::execute(const std::string& command) {
+  entries.push_back(Entry{"> " + command, COLOR_COMMAND});
+  scrollToBottom = true;
+
+  historyPos = -1;
+  history.erase(std::remove(history.begin(), history.end(), command),
+                history.end());
+  history.push_back(command);
+
+  if (command == "help") {
+    entries.push_back(
+        Entry{"Available commands: help, clear, history", COLOR_INFO});
+  } else if (command == "clear") {
+    clear();
+  } else if (command == "history") {
+    for (const std::string& past : history) {
+      entries.push_back(Entry{past, COLOR_DEFAULT});
+    }
+  } else if (commandCallback) {
+    commandCallback(*this, command);
+  } else {
+    entries.push_back(Entry{"Unknown command: '" + command + "'", COLOR_ERROR});
+  }
+}
+
+int ConsolePanel::textEditCallback(ImGuiInputTextCallbackData* data) {
+  if (data->EventFlag != ImGuiInputTextFlags_CallbackHistory) {
+    return 0;
+  }
+
+  const int previousPos = historyPos;
+  if (data->EventKey == ImGuiKey_UpArrow) {
+    if (historyPos == -1) {
+      historyPos = static_cast<int>(history.size()) - 1;
+    } else if (historyPos > 0) {
+      historyPos--;
+    }
+  } else if (data->EventKey == ImGuiKey_DownArrow) {
+    if (historyPos != -1 && ++historyPos >= static_cast<int>(history.size())) {
+      historyPos = -1;
+    }
+  }
+
+  if (previousPos != historyPos) {
+    const std::string& historyStr =
+        historyPos >= 0 ? history[static_cast<size_t>(historyPos)] : "";
+    data->DeleteChars(0, data->BufTextLen);
+    data->InsertChars(0, historyStr.c_str());
+  }
+
+  return 0;
+}
+
+void ConsolePanel::onUpdate(const FrameInfo&) {
+  ImGui::Begin("Console");
+
+  if (ImGui::SmallButton("Clear")) {
+    clear();
+  }
+  ImGui::SameLine();
+  ImGui::Checkbox("Auto-scroll", &autoScroll);
+
+  ImGui::Separator();
+
+  const float footerHeight =
+      ImGui::GetStyle().ItemSpacing.y + ImGui::GetFrameHeightWithSpacing();
+  ImGui::BeginChild("ScrollRegion", ImVec2(0, -footerHeight), false,
+                    ImGuiWindowFlags_HorizontalScrollbar);
+
+  for (const Entry& entry : entries) {
+    ImGui::PushStyleColor(ImGuiCol_Text, entry.color);
+    ImGui::TextUnformatted(entry.text.c_str());
+    ImGui::PopStyleColor();
+  }
+
+  if (scrollToBottom ||
+      (autoScroll && ImGui::GetScrollY() >= ImGui::GetScrollMaxY())) {
+    ImGui::SetScrollHereY(1.0f);
+  }
+  scrollToBottom = false;
+
+  ImGui::EndChild();
+  ImGui::Separator();
+
+  ImGuiInputTextFlags inputFlags = ImGuiInputTextFlags_EnterReturnsTrue |
+                                   ImGuiInputTextFlags_CallbackHistory;
+
+  bool reclaimFocus = false;
+  if (ImGui::InputText(
+          "Input", inputBuffer, sizeof(inputBuffer), inputFlags,
+          [](ImGuiInputTextCallbackData* data) -> int {
+            auto* console = static_cast<ConsolePanel*>(data->UserData);
+            return console->textEditCallback(data);
+          },
+          this)) {
+    std::string command{inputBuffer};
+    if (!command.empty()) {
+      execute(command);
+    }
+    inputBuffer[0] = '\0';
+    reclaimFocus = true;
+  }
+
+  ImGui::SetItemDefaultFocus();
+  if (reclaimFocus) {
+    ImGui::SetKeyboardFocusHere(-1);
+  }
+
+  ImGui::End();
+}
+
+}  // namespace sophia

engine/src/ui/panels/console_panel.hpp

@@ -0,0 +1,50 @@
+#pragma once
+
+#include <imgui.h>
+
+#include <functional>
+#include <sophia/frame_info.hpp>
+#include <sophia/ui/panel.hpp>
+#include <string>
+#include <vector>
+
+namespace sophia {
+
+class ConsolePanel : public Panel {
+ public:
+  using CommandCallback =
+      std::function<void(ConsolePanel&, const std::string&)>;
+
+  ConsolePanel() : Panel{"Console"} { registerDefaultCommands(); }
+
+  void onUpdate(const FrameInfo& frameInfo) override;
+
+  void log(const std::string& message);
+  void clear();
+
+  void setCommandCallback(CommandCallback callback) {
+    this->commandCallback = std::move(callback);
+  }
+
+ private:
+  struct Entry {
+    std::string text;
+    ImVec4 color;
+  };
+
+  void registerDefaultCommands();
+  void execute(const std::string& command);
+  int textEditCallback(struct ImGuiInputTextCallbackData* data);
+
+  std::vector<Entry> entries;
+  std::vector<std::string> history;
+  int historyPos = -1;
+
+  char inputBuffer[256] = {};
+  bool autoScroll = true;
+  bool scrollToBottom = false;
+
+  CommandCallback commandCallback;
+};
+
+}  // namespace sophia