Metrics: Changed io.MetricsActiveWindows to reflect the number of active windows (!= from visible windows), which is useful for lazy/idle render mechanisms as new windows are typically not visible for one frame. ...

Metrics: Added io.MetricsRenderWindow to reflect the number of visible windows.

Examples: OpenGL2: Disabling/restoring GL_LIGHTING and GL_COLOR_MATERIAL to increase compatibility with legacy OpenGL applications. (#1996)

Using limits.h LLONG_MIN etc. to increase old-compiler compatibility (as ll and ull prefixes were not standard). Not tested much on old compilers, relying on Clang/GCC warnings.

Update CONTRIBUTING.md

Changelog for #1989

imgui_impl_dx11: Using ID3D11Factory instead of ID3D11Factory1 (#1989)

Comments

Renamed io.OptResizeWindowsFromEdges to ConfigResizeWindowsFromEdges, io.OptCursorBlink to io.ConfigCursorBlink, io.OptMacOSXBehaviors to ConfigMacOSXBehaviors for consistency. (#1427, #1495, #822, #473, #650) ...

Demo: Exposed flags in Demo.

imgui_impl_glfw, imgui_impl_sdl: Workaround for Emscripten which doesn't seem to handle focus related calls. (#1941)

Added Visual Studio 2017+ build cruft to Ignore List (.vs/ folder)

Demo: Fix using ambiguous InputFloat() call which redirect to obsolete version. (#1990)

Fixed PushID() from keeping alive the new ID Stack top value (if a previously active widget shared the ID it would be erroneously kept alive) (drag and drop demo could soft-lock the UI until pressing Escape!)

Drag and Drop: Elapse payload as soon as delivery is made. (#153)

Drag and Drop: Added ImGuiDragDropFlags_SourceAutoExpirePayload flag to force payload to expire if the source stops being submitted. (#1725, #143).

Drag and Drop: Clear payload buffers more consistently in ClearDragAndDrop() + BeginDragDropTargetCustom() can't succeed with hidden contents. (#143)

Drag and Drop: Payload stays available and under the mouse if the source stops being submitted, however the tooltip is replaced by "..." + moved FrameScopeActive = false at the bottom of EndFrame() for safety. (#1725)

InvisibleButton: Added an assert to catch common type of passing zero-sized dimensions. (#1983)

imgui_impl_opengl3: Comments. (#1987)

Made assertion more clear when trying to call Begin() outside of the NewFrame()..EndFrame() scope. (#1987)

Fixes for pre-C++11 compilers. ...

That said, I think we can consider upgrading requirement to an early VS-friendly subset of C++11. The thing I would like the most from C++11 are forward-declared enum (from VS 2012 onward).

Internals: Changed signature of ShadeVerts functions to remove pointers. (#1286, #1700, #1986)

Revert "Assert that fmt != NULL before calling vsnprintf (#1969)" ...

This reverts commit 84183f5.

Speculative va_copy() fix for old versions of GCC/Clang. (cannot repro) (#1085)

Visual Studio: calling into _vsnprintf. (#1085)

Examples: imgui_impl_opengl3.cpp Using #ifdef GL_SAMPLER_BINDING instead of if (glBindSampler) (#1985)

Internals: Fixed HoveredIdTimer so it is safe to call SetHoveredId() multiple times without altering the timer.

Demo: Added extra demo in the Basic Horizontal Layout section. (#1977) + PR guidelines

ImFontAtlas::AddFontDefault: Made it possible to override glyph ranges. (#1965)

Examples: imgui_impl_osx: Fix for incorrect DeltaTime calculation on mac OS. (#1978)

Examples: OpenGL3: Tweaks, added changelog. (#1941)