Frame hover glitch when moving on adjacent item border, with SetNextItemAllowOverlap

[wolfgang371]

ImGui.set_next_item_allow_overlap # important
ImGui.button("##button1", ImVec2.new(50.0,50.0))
h1 = ImGui.is_item_hovered
ImGui.button("##button2", ImVec2.new(50.0,50.0)) # button or dummy, irrelevant
# ImGui.dummy(ImVec2.new(50.0,50.0)) # button or dummy, irrelevant
h2 = ImGui.is_item_hovered
puts [ImGui.get_frame_count, h1 ? "hover top button" : nil, h2 ? "hover bottom button" : nil].reject(&.nil?).join(", ")

produces something like this...

when moving down (good)

185, hover top button
186, hover bottom button

when moving up (bad)

194, hover bottom button
195
196, hover top button

Version/Branch of Dear ImGui: 1.89.9 master
Back-ends: crsfml, 2.5.3
Compiler, OS: gcc/crystal, Ubuntu

[ocornut]

Hello,

This is expected with how AllowOverlap mode is implemented. It requires an extra frame before hovering starts being reported, to ensure a subsequent item is not overlapping our item. I don't expect to be able to change this.

(I know this is a manufactured repro, and it's great submitted as is! But obviously in your example the button are not overlapping. I wonder what your actual problem encompassing the several overlap-related issues is)

C++ repro

// #7514
{
    ImGui::SeparatorText("#7514");
    ImGui::SetNextItemAllowOverlap();
    ImGui::Button("Button1", { 50.0f, 50.0 });
    bool h1 = ImGui::IsItemHovered();
    ImGui::Button("Button2", { 50.0, 50.0 });// # button or dummy, irrelevant
    //ImGui::Dummy({ 50.0, 50.0});// # button or dummy, irrelevant
    bool h2 = ImGui::IsItemHovered();
    //if (h1 || h2)
    if (ImGui::IsWindowHovered())
        printf("[%05d] %s%s\n", ImGui::GetFrameCount(), h1 ? "hover top button" : "", h2 ? "hover bottom button" : "");
}

[wolfgang371]

Hi @ocornut,
thanks for having a look - regarding your question (my actual problem) / just for the record: this is related to #7510.
With the glitch from above and some of the workarounds from the other issue, the hovered InputText would "blink out" for one frame - not a big deal/nuisance, sure.