Assertion failed: node->IsLeafNode()

[qq1768101247]

Version/Branch of Dear ImGui:

Version 1.92.6 WIP, Branch: docking

Back-ends:

imgui_impl_opengl3.cpp + imgui_impl_glfw.cpp

Compiler, OS:

Windows 11 + MSVC 2022

Full config/build information:

Dear ImGui 1.92.6 WIP (19252)
--------------------------------
sizeof(size_t): 8, sizeof(ImDrawIdx): 4, sizeof(ImDrawVert): 20
define: __cplusplus=199711
define: _WIN32
define: _WIN64
define: _MSC_VER=1944
define: _MSVC_LANG=202002
define: IMGUI_HAS_VIEWPORT
define: IMGUI_HAS_DOCK
IM_ASSERT: runs expression: OK. expand size: OK
--------------------------------
io.BackendPlatformName: imgui_impl_glfw (3400)
io.BackendRendererName: imgui_impl_opengl3
io.ConfigFlags: 0x00000483
 NavEnableKeyboard
 NavEnableGamepad
 DockingEnable
 ViewportsEnable
io.ConfigViewportsNoAutoMerge
io.ConfigViewportsNoDefaultParent
io.ConfigNavCaptureKeyboard
io.ConfigInputTextCursorBlink
io.ConfigWindowsResizeFromEdges
io.ConfigMemoryCompactTimer = 60.0
io.BackendFlags: 0x00001C16
 HasMouseCursors
 HasSetMousePos
 PlatformHasViewports
 HasMouseHoveredViewport
 RendererHasTextures
 RendererHasViewports
--------------------------------
io.Fonts: 1 fonts, Flags: 0x00000000, TexSize: 1024,1024
io.Fonts->FontLoaderName: stb_truetype
io.DisplaySize: 3200.00,1876.00
io.DisplayFramebufferScale: 1.00,1.00
--------------------------------
style.WindowPadding: 8.00,8.00
style.WindowBorderSize: 1.00
style.FramePadding: 4.00,3.00
style.FrameRounding: 0.00
style.FrameBorderSize: 0.00
style.ItemSpacing: 8.00,4.00
style.ItemInnerSpacing: 4.00,4.00

Details:

I came across this alert: Assertion failed: node->IsLeafNode() && "If you get this assert: please submit .ini file + repro of actions leading to this.", file D:\xxx\ImGui\imgui.cpp, line 18609
`[Window][ParamPool]
Pos=2500,34
Size=700,1842
Collapsed=0
DockId=0x00000008,1

[Window][WayPoint Control##AirLineRender]
Pos=2500,34
Size=700,1842
Collapsed=0
DockId=0x00000008,0

[Window][MMS status##MMSStatus]
Pos=0,34
Size=599,475
Collapsed=0
DockId=0x0000000D,0

[Window][Primary Flight Display (PFD)]
Pos=0,1158
Size=599,718
Collapsed=0
DockId=0x0000000C,0

[Window][Lamp]
Collapsed=0
DockId=0x00000003

[Window][Battery]
Collapsed=0
DockId=0x00000004

[Window][MODES##ModeVector]
Pos=0,511
Size=599,645
Collapsed=0
DockId=0x0000000E,0

[Window][Plane Attitude]
Collapsed=0
DockId=0x00000005

[Window][All Message]
Collapsed=0
DockId=0x00000006

[Window][WindowOverViewport_11111111]
Pos=0,34
Size=3200,1842
Collapsed=0

[Window][Debug##Default]
ViewportPos=60,100
ViewportId=0x16723995
Size=400,400
Collapsed=0

[Window][ICON]
ViewportPos=60,100
ViewportId=0x10E6F3B6
Size=435,94
Collapsed=0

[Window][Status]
Pos=2315,1454
Size=185,107
Collapsed=0

[Window][Dear ImGui Demo]
ViewportPos=650,60
ViewportId=0x59819E39
Size=550,680
Collapsed=0

[Window][About Dear ImGui]
ViewportPos=423,621
ViewportId=0x28EBAACF
Size=833,898
Collapsed=0

[Docking][Data]
DockSpace ID=0x08BD597D Window=0x1BBC0F80 Pos=0,74 Size=3200,1842 Split=X
DockNode ID=0x00000009 Parent=0x08BD597D SizeRef=599,1876 Split=Y
DockNode ID=0x0000000B Parent=0x00000009 SizeRef=599,1143 Split=Y
DockNode ID=0x0000000D Parent=0x0000000B SizeRef=599,484 Selected=0xA097ACF1
DockNode ID=0x0000000E Parent=0x0000000B SizeRef=599,657 Selected=0x8B760DD6
DockNode ID=0x0000000C Parent=0x00000009 SizeRef=599,731 Selected=0x48EA8B2D
DockNode ID=0x0000000A Parent=0x08BD597D SizeRef=2599,1876 Split=X
DockNode ID=0x00000007 Parent=0x0000000A SizeRef=2498,1876 CentralNode=1
DockNode ID=0x00000008 Parent=0x0000000A SizeRef=700,1876 Selected=0x15D1C719
DockNode ID=0x44FDDFEC Pos=800,509 Size=1600,938 Split=X
DockNode ID=0x00000001 Parent=0x44FDDFEC SizeRef=799,938 Split=X
DockNode ID=0x00000003 Parent=0x00000001 SizeRef=398,938
DockNode ID=0x00000004 Parent=0x00000001 SizeRef=399,938
DockNode ID=0x00000002 Parent=0x44FDDFEC SizeRef=799,938 Split=X
DockNode ID=0x00000005 Parent=0x00000002 SizeRef=398,938
DockNode ID=0x00000006 Parent=0x00000002 SizeRef=399,938

`

Screenshots/Video:

No response

Minimal, Complete and Verifiable Example code:

auto MainDockSpaceID = ImGui::DockSpaceOverViewport(0, ImGui::GetMainViewport(), ImGuiDockNodeFlags_PassthruCentralNode);
mms_pfd_id = ImGui::DockBuilderSplitNode(MainDockSpaceID, ImGuiDir_Left, 600 / 3200.0f, nullptr, nullptr);
ImGui::DockBuilderSplitNode(mms_pfd_id, ImGuiDir_Up, 0.61f, &mms_mode_id, &pfd_id);
ImGui::DockBuilderSplitNode(mms_mode_id, ImGuiDir_Up, 0.425f, &mms_id, &mode_id);
if (auto node_mms_mode = ImGui::DockBuilderGetNode(mms_pfd_id)) {
    node_mms_mode->SetLocalFlags(node_mms_mode->LocalFlags | ImGuiDockNodeFlags_CentralNode);
}
if (auto node_pfd = ImGui::DockBuilderGetNode(pfd_id)) {
    node_pfd->SetLocalFlags(node_pfd->LocalFlags | ImGuiDockNodeFlags_HiddenTabBar);
}
if (auto node_mms = ImGui::DockBuilderGetNode(mms_id)) {
    node_mms->SetLocalFlags(node_mms->LocalFlags | ImGuiDockNodeFlags_HiddenTabBar);
}
if (auto node_mode = ImGui::DockBuilderGetNode(mode_id)) {
    node_mode->SetLocalFlags(node_mode->LocalFlags | ImGuiDockNodeFlags_HiddenTabBar);
}

ImGui::DockBuilderDockWindow("MMS status##MMSStatus", mms_id);
ImGui::DockBuilderDockWindow("Primary Flight Display (PFD)", pfd_id);
ImGui::DockBuilderDockWindow("MODES##ModeVector", mode_id);

ImGui::Begin("MMS status##MMSStatus");
ImGui::End();

ImGui::Begin("Primary Flight Display (PFD)");
ImGui::End();

ImGui::Begin("MODES##ModeVector");
ImGui::End();

[qq1768101247]

The above static assertion is caused by me wanting to set a main close button for the three windows in this docking space(mms_pfd_id), but I don't know how to do it.

[qq1768101247]

Now they have way too many close buttons, which makes it look very messy.

[ocornut]

Linking to #9070 for reference. Will investigate.

[ocornut]

Your .ini data has two nodes marked CentralNode=1 and one of them is not a leaf node.

That code is forcefully setting that flag:

 node_mms_mode->SetLocalFlags(node_mms_mode->LocalFlags | ImGuiDockNodeFlags_CentralNode);

Don't do this.

About close button please open a separate issue and clarify exactly what you need.
I don't know what "set a main close button for the three windows in this docking" means. I presume you'd want to hide either the window either the node close button when there's only a single window in a node?