Skip to content

Sync LWJGL backends with ImGui upstream (OpenGL3 + GLFW)#391

Merged
SpaiR merged 2 commits intomainfrom
feat/update-lwjgl-backend
Apr 25, 2026
Merged

Sync LWJGL backends with ImGui upstream (OpenGL3 + GLFW)#391
SpaiR merged 2 commits intomainfrom
feat/update-lwjgl-backend

Conversation

@SpaiR
Copy link
Copy Markdown
Owner

@SpaiR SpaiR commented Apr 25, 2026 •
edited
Loading

Update LWJGL Backend Implementations to Match Recent ImGui C++ Changes

Summary

This PR synchronizes the imgui-java LWJGL backend implementations with the latest Dear ImGui C++ code (commit 32f4c23). The changes modernize OpenGL 3 rendering and GLFW platform integration to support contemporary graphics configurations and improve compatibility across platforms.

Key Changes

ImGuiImplGl3.java:

  • Updated to the latest C++ imgui_impl_opengl3.cpp reference implementation
  • Enhanced OpenGL ES 3.0 profile detection for improved cross-platform support
  • Added runtime GL_MAX_TEXTURE_SIZE querying for proper texture management
  • Introduced feature detection flags (hasPolygonMode, hasBindSampler) for better ES3 compatibility
  • Fixed texture wrapping parameters (GL_CLAMP_TO_EDGE) and pixel alignment settings
  • Added comprehensive comments aligned with upstream C++ structure for maintainability
  • Improved GL state backup/restore logic for compatibility with modern GLFW versions

ImGuiImplGlfw.java:

  • Synchronized with the latest C++ imgui_impl_glfw.cpp reference implementation
  • Added multi-API support (OpenGL, Vulkan, Other) through new initialization methods
  • Implemented runtime Wayland detection to properly gate multi-viewport support on Linux
  • Enhanced key translation including support for GLFW_KEY_WORLD_1 and GLFW_KEY_WORLD_2
  • Fixed mouse cursor state management and added caching to reduce redundant GLFW calls
  • Improved DPI awareness with new helper functions: getContentScaleForWindow() and getContentScaleForMonitor()
  • Added Linux-specific workarounds for mouse event handling during focus loss
  • Updated monitor enumeration logic to handle edge cases (zero DPI, null video modes)
  • Added portable sleep helper function
  • Better platform-specific handling (Windows, macOS, Linux/Wayland) with explanatory comments for Java divergences

Type of change

  • Minor changes or tweaks (quality of life stuff)
  • Bug fix (non-breaking change which fixes an issue)
  • New feature (non-breaking change which adds functionality)
  • Breaking change (fix or feature that would cause existing functionality to not work as expected)
  • This change requires a documentation update

SpaiR and others added 2 commits April 25, 2026 15:13
@SpaiR @claude
feat: synchronize GLFW with upstream imgui_impl_glfw.cpp (32f4c23)
6f30afc 
- Add init overloads for OpenGL, Vulkan, and generic rendering
- Pick up upstream input fixes (GLFW_KEY_WORLD_1/2 mapping, key translation, mouse-leave sentinel)
- Improve monitor tracking: skip zero-size/DPI monitors, preserve list on no-valid-monitor
- Add cursor caching to suppress redundant glfwSetCursor/glfwSetInputMode calls
- Add helpers: isWayland, getContentScaleForWindow/Monitor, getWindowSizeAndFramebufferScale, sleep
- Skip PlatformHasViewports on Wayland
- Fix glfwHawWindowTopmost typo → glfwHasWindowTopmost
- Document intentional omissions (Vulkan, Win32 WndProc, X11 SetWindowFloating, legacy fns)
- Report runtime GLFW version in platform name

Co-authored-by: Claude <noreply@anthropic.com>
@SpaiR @claude
feat: synchronize GL3 backend with upstream imgui_impl_opengl3.cpp (3…
0411daf 
…2f4c23)

Mirror upstream capability gating (HasPolygonMode, HasBindSampler, HasClipOrigin,
MaxTextureSize, ES3-on-desktop detection), save/restore order in RenderDrawData,
GL_PIXEL_UNPACK_BUFFER backup in createDeviceObjects, font-texture GL_UNPACK_ALIGNMENT=1
and GL_CLAMP_TO_EDGE wraps, and multi-viewport clear color (0,0,0,1). Intentionally
omitted upstream pieces carry inline comments pointing at follow-up work. Restore the
GLFW framebuffer-scale Linux non-Wayland override (forces 1,1) that was held back
during the earlier GLFW sync.

Co-authored-by: Claude <noreply@anthropic.com>
@SpaiR SpaiR added the chore Routine tasks, refactoring, updates, minor improvements label Apr 25, 2026
@SpaiR SpaiR changed the title Feat/update lwjgl backend Sync LWJGL backends with ImGui upstream (OpenGL3 + GLFW) Apr 25, 2026
@SpaiR SpaiR self-assigned this Apr 25, 2026
@SpaiR SpaiR merged commit c729326 into main Apr 25, 2026
7 checks passed
@SpaiR SpaiR deleted the feat/update-lwjgl-backend branch April 25, 2026 13:19
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Reviewers

No reviews

Assignees

@SpaiR SpaiR

Labels

chore Routine tasks, refactoring, updates, minor improvements

Projects

None yet

Milestone

No milestone

Development

Successfully merging this pull request may close these issues.

1 participant

@SpaiR