Hello ImGui Files

• Update ImGui to v1.92.9b-docking

New Callbacks:

• Add BeforeSwap callback (thanks to @wkjarosz): called after ImGui's draw data was rendered to the 3D backend, but before the frame is swapped to the screen. Enables a final full-screen post-process pass over the whole frame (e.g. a color-management pass), which is not possible with BeforeImGuiRender (too early: the draw data is not rendered yet) nor with AfterSwap (too late: the frame is already presented).
• Add ConfirmExit callback: called when the user requests to close the app window (window close button, Cmd-Q / Alt-F4, or the App/Quit menu). Return false to cancel the exit, e.g. to confirm quitting when there are unsaved changes.

RendererBackendOptions:

• requestFloatBuffer is now also supported by the OpenGL3 + Glfw backend (it used to be Metal-only), enabling HDR/EDR display output on Windows and Linux (thanks to @wkjarosz). This requires a GLFW that defines GLFW_FLOATBUFFER (no stock release does yet, but HDR-enabling forks such as https://github.com/Tom94/glfw do); it is silently ignored otherwise. HelloImGui now probes whether a floating point framebuffer can actually be created, and resets requestFloatBuffer to false if not, so applications can read the field back to know what they got. See the new hello_edr_opengl demo. Note: on macOS, EDR output still requires the Metal backend.

HighDPI:

• Fonts are now scaled via style.FontScaleDpi instead of at load time (finalizes the ImGui v1.92 transition). Breaking change: removes FontLoadingParams::adjustSizeToDpi and DpiFontLoadingFactor()

Widgets:

• WidgetWithResizeHandle: the handle color now uses ImGuiCol_ResizeGrip (with alphaMul=0.5)
• InputTextResizable: can now be resized even inside a node (node editor)

Fixes:

• AssetFileFullPath can find files in the current folder (was broken)
• Fix an MSVC internal compiler error on plutovg-font.c (compile it with /Od)

Internals:

• ManualRender: refactor behavior, simpler and closer to ImmApp::ManualRender

Contributions:

• Add BeforeSwap render-loop callback by @wkjarosz in https://github.com/pthom/hello_imgui/pull/166
• Support requestFloatBuffer on the OpenGL3 + Glfw backend by @wkjarosz in https://github.com/pthom/hello_imgui/pull/167

Full diff: https://github.com/pthom/hello_imgui/compare/v1.92.700...v1.92.900