SDL2+Wayland+Touch - TabItem only activated after second touch

[elfenix]

Version/Branch of Dear ImGui:

Version: v1.87 (exact tag)
Branch: master

Back-end/Renderer/Compiler/OS

Back-ends: imgui_impl_sdl.cpp + imgui_impl_opengl3.cpp
Compiler: gcc 9.3.0
Operating System: embedded linux w/ wayland

My Issue/Question:

A handful of widgets seem to require more than one touch event to activate. I'm utilizing ImGui on a touch screen device without keyboard or mouse. The device runs wayland (no X11).

Screenshots/Video

(None Currently)

Standalone, minimal, complete and verifiable example:

The ImGui demo recreates this issue with no modifications.

Inside the demo window, select the "Tab widget". Tapping on the tab items consistently requires 2 touches to have the tab switch. The majority of other widgets appear to work fine - buttons require only a single press generally.

Hacky (Fix?)

A (probably incorrect) code change seemed to get behavior as desired was responding to SDL_FINGERUP, inside of imgui_impl_sdl.cpp . Enabling the preprocessor block here results in the desired behavior - but I'm not entirely certain what the exact chain of events is or if the behavior I'm creating is correct or not. (Also - probably wrong if we're dealing with Mouse + Touch screen interactions!) Still need to debug.

On my version of SDL, the FINGERUP appears to happen after the "button release" event.

bool ImGui_ImplSDL2_ProcessEvent(const SDL_Event* event)
{
    ImGuiIO& io = ImGui::GetIO();
    ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();

    switch (event->type)
    {
        case SDL_FINGERUP:
        {
#if 0
            printf("FINGER UP EVENT - Set Mouse Pos - Single Clikck on Tab Item OK!\n");
            io.AddMousePosEvent(-1, -1);
            return true;
#else
            printf("FINGER UP IGNORED - Do nothing (current behavior)\n");
#endif
            break;
        }

[ocornut]

Same as #2702, moving there!