feat(gameclient): Introduce imgui framework

[jurassicLizard]

Note : to test this please configure in Debug mode before building with -A Win32 ~~-DRTS_BUILD_OPTION_DEBUG=ON~~ -DRTS_BUILD_OPTION_IMGUI=On

all the code is gated behind a RTS_IMGUI_ENABLED perprocessor define for debugging purposes

• What it does : Integrates the Dear Imgui framework and loads a console and demo window overlay
  in debug mode (generalsv, generalszh, WorldBuilderV and WorldBuilderZH)

• What is missing

  • Some useful command or Ideas what it should look like : this PR will just focus on build and runtime integration via ImGui Demo
  • Currently it is permanently enabled when the game is builtwith the imgui option on Gated behind RTS_BUILD_OPTION_IMGUI
  • Code cleanup and SuperHackers Comments etc... done
  • Backporting to Generals done

[greptile-apps]

Greptile Overview

Greptile Summary

Integrates Dear ImGui framework into both Generals and Zero Hour (plus WorldBuilder tools) with a custom DirectX 8 backend, gated behind the RTS_BUILD_OPTION_IMGUI build flag and RTS_HAS_IMGUI preprocessor define.

Key Changes:

• Custom DX8 backend implementation (imgui_impl_dx8.cpp/h) with proper state management, error checking, and stencil-based clipping
• Frame manager wrapper (ImGuiFrameManager) to handle BeginFrame/EndFrame lifecycle with guard against double-calls
• Input forwarding through ImGui_ImplWin32_WndProcHandler in WndProc
• Device lifecycle integration: initialization in Create_Device(), cleanup in Shutdown(), and device reset handling with InvalidateDeviceObjects/CreateDeviceObjects
• Render integration in DX8Wrapper::End_Scene() after main scene rendering
• Game loop integration in GameClient::update() with BeginFrame/ShowDemoWindow/EndFrame, correctly placed before early returns
• CMake configuration fetches ImGui v1.91.6 from upstream and builds with custom imconfig.h
• Comprehensive documentation comments explaining the integration workflow

Implementation Quality:

• The integration follows ImGui best practices with proper initialization order and frame lifecycle management
• Consistent implementation across Generals/GeneralsMD and their WorldBuilder tools
• All code properly gated behind preprocessor defines for clean builds without ImGui
• Previous review comments have been addressed (redundant Render() calls fixed, error checking added)

Confidence Score: 5/5

• This PR is safe to merge with no significant issues found
• The implementation demonstrates solid engineering with proper error handling, clean separation of concerns, consistent application across codebase variants, comprehensive documentation, and all previously identified issues have been addressed. The code is well-guarded with preprocessor defines and follows ImGui integration best practices.
• No files require special attention

Important Files Changed

Filename	Overview
Core/Libraries/Source/ImGui/dx8_backend/imgui_impl_dx8.cpp	Custom DirectX 8 backend for ImGui with proper error checking, device state management, and stencil-based clipping implementation
Core/Libraries/Source/ImGui/wrapper/ImGuiFrameManager.h	Well-documented wrapper interface with clear separation of concerns comment explaining RenderDrawData is called separately
Generals/Code/GameEngine/Source/GameClient/GameClient.cpp	ImGui integrated into game loop with BeginFrame/ShowDemoWindow/EndFrame at correct points, including before early returns
GeneralsMD/Code/GameEngine/Source/GameClient/GameClient.cpp	Zero Hour variant with identical ImGui integration pattern to Generals
Generals/Code/Libraries/Source/WWVegas/WW3D2/dx8wrapper.cpp	DX8 device lifecycle integration with ImGui initialization, device object management, and render call in End_Scene()
GeneralsMD/Code/Libraries/Source/WWVegas/WW3D2/dx8wrapper.cpp	Zero Hour DX8 wrapper with identical ImGui integration to Generals variant

Sequence Diagram

sequenceDiagram
    participant User
    participant WndProc
    participant DX8Wrapper
    participant GameClient
    participant ImGuiWin32
    participant ImGuiDX8
    participant Display

    Note over DX8Wrapper: Application Initialization
    DX8Wrapper->>DX8Wrapper: Create_Device()
    DX8Wrapper->>ImGuiWin32: ImGui_ImplWin32_Init()
    DX8Wrapper->>ImGuiDX8: ImGui_ImplDX8_Init()
    DX8Wrapper->>ImGuiDX8: CreateDeviceObjects()

    Note over User,Display: Main Game Loop
    User->>WndProc: Input Events (mouse, keyboard)
    WndProc->>ImGuiWin32: ImGui_ImplWin32_WndProcHandler()
    ImGuiWin32-->>WndProc: Returns handled status

    GameClient->>GameClient: update()
    GameClient->>ImGuiDX8: BeginFrame() [NewFrame sequence]
    GameClient->>ImGuiWin32: NewFrame()
    GameClient->>GameClient: ImGui::ShowDemoWindow()
    GameClient->>GameClient: EndFrame() [Render()]
    GameClient->>Display: DRAW()
    Display->>DX8Wrapper: End_Scene()
    DX8Wrapper->>ImGuiDX8: ImGui_ImplDX8_RenderDrawData()
    ImGuiDX8->>ImGuiDX8: SetupRenderState()
    ImGuiDX8->>DX8Wrapper: DrawIndexedPrimitive()

    Note over DX8Wrapper: Device Reset Handling
    DX8Wrapper->>ImGuiDX8: InvalidateDeviceObjects()
    DX8Wrapper->>DX8Wrapper: Reset D3D Device
    DX8Wrapper->>ImGuiDX8: CreateDeviceObjects()

    Note over DX8Wrapper: Application Shutdown
    DX8Wrapper->>ImGuiDX8: ImGui_ImplDX8_Shutdown()
    DX8Wrapper->>ImGuiWin32: ImGui_ImplWin32_Shutdown()
    DX8Wrapper->>DX8Wrapper: DestroyContext()

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[greptile-apps]

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[jurassicLizard]

@greptileai

[jurassicLizard]

relates to : #387 and #2084 (comment)

[greptile-apps]

_{14 files reviewed, 1 comment}

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[greptile-apps]

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[jurassicLizard]

@greptileai

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[jurassicLizard]

A tip for bringing the DX8 backend code style closer to the original DX9 backend code: Use a diff tool and put them side by side, then merge over to DX8 everything that should not be different.

A tip for bringing the DX8 backend code style closer to the original DX9 backend code: Use a diff tool and put them side by side, then merge over to DX8 everything that should not be different.

Thanks. i did exactly that but given the large differences between both backends, some braces might slip the net while i am scanning. i hope i got them all now

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[xezon]

Several comments were left unanswered. GitHub collapses them, so you need to press a button to uncollapse them:

[jurassicLizard]

Several comments were left unanswered. GitHub collapses them, so you need to press a button to uncollapse them:

will do , i am getting a spaghetti in my screen with all the greptile stuff and my own stuff its getting harder to find things

[jurassicLizard]

@greptileai

[jurassicLizard]

@xezon since it is no longer active only in Debug mode, i think the Debug label no longer fits . what do you think ?

[xezon]

Debug label is ok. It is meant to be compiled out in regular builds for Players. Just because it does not sit behind RTS_DEBUG does not mean it is no Debug.