Dear ImGui Bundle Files

ImmVision: OpenCV is now optional / use GPU rendering pipeline

ImmVision no longer requires OpenCV: this way the compilation and installation of the library is much faster, and the resulting binaries are smaller.

All image processing (color conversion, statistics, alpha blending, drawing annotations, zoom/pan transform, image saving) has been reimplemented without OpenCV dependencies.

• New core types: ImageBuffer, Point, Point2d, Size, Matrix33d replace cv::Mat and OpenCV geometric types in all public APIs
• Zero-copy interop: When OpenCV is available (IMMVISION_HAS_OPENCV), cv::Mat converts seamlessly to/from ImageBuffer via implicit constructors
• Python: No change for Python users — ImmVision continues to use numpy arrays (the cvnp_nano bridge has been removed)
• Drawing primitives: Custom bitmap font and Bresenham drawing replace OpenCV's putText, line, ellipse, rectangle
• Image saving: Uses stb_image_write (PNG/JPG/BMP/TGA/HDR) instead of cv::imwrite
• Zoom/pan: Custom implementation with nearest, bilinear, and area-based downscaling
• ImmDebug API change: ImmDebug() now assumes RGB (the common default); use ImmDebugBgr() for OpenCV BGR images. Fixed per-image color order handling in the viewer.
• Smaller wheels: ~16% size reduction across all platforms (45 MB total savings)
• Faster CI builds: 5–8 minutes faster per platform (no more OpenCV compilation)
• New features: colormap support for single-channel integer images, multithreaded pixel drawing/resize, fixed watched pixel delete button visibility

The ImmVision rendering pipeline has been rewritten to use GPU texture sampling and ImGui DrawList:

• GPU zoom/pan: Image uploaded to GPU texture once (with mipmaps); pan/zoom handled via UV coordinates — no more per-frame CPU warp
• Mipmap filtering: GL_NEAREST at high zoom (pixel-perfect), GL_LINEAR for moderate zoom, GL_LINEAR_MIPMAP_LINEAR for downsampling (high-quality anti-aliasing)
• DrawList annotations: Grid lines, pixel values, and watched pixel markers drawn via ImGui DrawList in screen space (TrueType font replaces bitmap font)
• DrawList backgrounds: School paper and alpha checkerboard rendered via DrawList (no longer composited into texture)
• Inspector redesign: Horizontal filmstrip with scrolling and adjustable thumbnail size replaces the old vertical listbox
• Other fixes: "Export colormap image" now available for uint8 images with colormap; save dialog remembers last directory

demo_imgui_bundle (aka "Dear ImGui Bundle Explorer")

• Display version and compilation time at startup (C++, emscripten and Python versions)
• Python demo code is also shown in the python version (when installed from Pypi)

hello_imgui

• Fix potential memory error in font handling (_LoadFontImpl: pass font buffer allocated with IM_ALLOC)
• Add HelloImGui::LoadImageDataFromAsset() — decode an image from assets into CPU memory (C++ only)
• Compile imgui_impl_metal.mm and MetalNanoVG with -fobjc-arc (fixes ARC bridge cast warnings)
• Workaround plutovg file(RELATIVE_PATH) error with relative CMAKE_INSTALL_PREFIX (scikit-build-core)

Build & warnings cleanup

We are now at zero-warnings, on all CI / platforms and configs.

• CMake: fetch freetype & plutovg with EXCLUDE_FROM_ALL
• CMake: fix ImAnim exclusion when IMGUI_BUNDLE_WITH_IMANIM_FULL_DEMOS is off
• CMake: ibd_add_this_folder_as_demos_library now links demo_utils (fixes GCC linker error)
• CMake: suppress Apple ld duplicate library warnings
• CMake: suppress third-party warnings (ImAnim: -Wno-unused-result, -Wno-nontrivial-memaccess; plutosvg: -Wno-deprecated-declarations)
• CMake: normalize install path (./lib/ → lib) to fix CMP0177 warning
• Fix ImFileDialog u8path deprecation warning (C++20 compatibility)
• Fix GCC -Wformat-truncation warning in demo_imgui_bundle_intro.cpp

Contributors

• Fix mouse click for pygame backend by @anhddo in https://github.com/pthom/imgui_bundle/pull/448

Full Changelog: https://github.com/pthom/imgui_bundle/compare/v1.92.600...v1.92.601