From 2593b6a1c86dcfc2fee95bbe55fbd9ae04d5991c Mon Sep 17 00:00:00 2001
From: Rokas Kupstys <rokups@zoho.com>
Date: Mon, 27 Apr 2020 12:01:59 +0300
Subject: [PATCH] Drag and Drop: Fix unintended fallback "..." tooltip during
 drag operation when drag source uses _SourceNoPreviewTooltip flags. (#3160)

---
 docs/CHANGELOG.txt | 4 +++-
 imgui.cpp          | 2 +-
 imgui.h            | 1 +
 3 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/docs/CHANGELOG.txt b/docs/CHANGELOG.txt
index 704801877..11a9560c8 100644
--- a/docs/CHANGELOG.txt
+++ b/docs/CHANGELOG.txt
@@ -49,8 +49,10 @@ Other Changes:
 - Backends: Win32: Support for #define NOGDI, won't try to call GetDeviceCaps(). (#3137, #2327)
 - Backends: OpenGL: Fixed handling of GL 4.5+ glClipControl(GL_UPPER_LEFT) by inverting the
   projection matrix top and bottom values. (#3143, #3146) [@u3shit]
-- Backends: Vulkan: Fixed edge case where render callbacks wouldn't be called if the ImDrawData 
+- Backends: Vulkan: Fixed edge case where render callbacks wouldn't be called if the ImDrawData
   structure didn't have any vertices. (#2697) [@kudaba]
+- Drag and Drop: Fixed unintended fallback "..." tooltip display during drag operation when
+  drag source uses _SourceNoPreviewTooltip flags. (#3160) [@rokups]
 
 
 -----------------------------------------------------------------------
diff --git a/imgui.cpp b/imgui.cpp
index f900a0103..8e66bbed8 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -4216,7 +4216,7 @@ void ImGui::EndFrame()
     }
 
     // Drag and Drop: Fallback for source tooltip. This is not ideal but better than nothing.
-    if (g.DragDropActive && g.DragDropSourceFrameCount < g.FrameCount)
+    if (g.DragDropActive && g.DragDropSourceFrameCount < g.FrameCount && !(g.DragDropSourceFlags & ImGuiDragDropFlags_SourceNoPreviewTooltip))
     {
         g.DragDropWithinSource = true;
         SetTooltip("...");
diff --git a/imgui.h b/imgui.h
index d3460d728..5420ac536 100644
--- a/imgui.h
+++ b/imgui.h
@@ -644,6 +644,7 @@ namespace ImGui
 
     // Drag and Drop
     // - [BETA API] API may evolve!
+    // - If you stop calling BeginDragDropSource() the payload is preserved however it won't have a preview tooltip (we currently display a fallback "..." tooltip as replacement)
     IMGUI_API bool          BeginDragDropSource(ImGuiDragDropFlags flags = 0);                                      // call when the current item is active. If this return true, you can call SetDragDropPayload() + EndDragDropSource()
     IMGUI_API bool          SetDragDropPayload(const char* type, const void* data, size_t sz, ImGuiCond cond = 0);  // type is a user defined string of maximum 32 characters. Strings starting with '_' are reserved for dear imgui internal types. Data is copied and held by imgui.
     IMGUI_API void          EndDragDropSource();                                                                    // only call EndDragDropSource() if BeginDragDropSource() returns true!