ImDrawList: Additional comments and extracted bits into ImDrawList::PopUnusedDrawCmd()
diff --git a/docs/CHANGELOG.txt b/docs/CHANGELOG.txt
index 5f9f7b1..6ab1019 100644
--- a/docs/CHANGELOG.txt
+++ b/docs/CHANGELOG.txt
@@ -61,6 +61,8 @@
[@thedmd, @Shironekoben, @sergeyn, @ocornut]
- ImDrawList, ImDrawListSplitter, Columns: Fixed an issue where starting a split when current
VtxOffset was not zero would lead to draw commands with wrong VtxOffset. (#2591)
+- ImDrawList, ImDrawListSplitter, Columns: Fixed an issue where starting a split right after
+ a callback draw command would incorrectly override the callback draw command.
- Misc, Freetype: Fix for rare case where FT_Get_Char_Index() succeed but FT_Load_Glyph() fails.
- CI: Added CI test to verify we're never accidentally dragging libstdc++ (on some compiler setups,
static constructors for non-pod data seems to drag in libstdc++ due to thread-safety concerns).
diff --git a/imgui.cpp b/imgui.cpp
index 95dc22a..1b190a6 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -4077,18 +4077,12 @@
static void AddDrawListToDrawData(ImVector<ImDrawList*>* out_list, ImDrawList* draw_list)
{
+ // Remove trailing command if unused.
+ // Technically we could return directly instead of popping, but this make things looks neat in Metrics window as well.
+ draw_list->PopUnusedDrawCmd();
if (draw_list->CmdBuffer.Size == 0)
return;
- // Remove trailing command if unused
- ImDrawCmd* curr_cmd = &draw_list->CmdBuffer.back();
- if (curr_cmd->ElemCount == 0 && curr_cmd->UserCallback == NULL)
- {
- draw_list->CmdBuffer.pop_back();
- if (draw_list->CmdBuffer.Size == 0)
- return;
- }
-
// Draw list sanity check. Detect mismatch between PrimReserve() calls and incrementing _VtxCurrentIdx, _VtxWritePtr etc.
// May trigger for you if you are using PrimXXX functions incorrectly.
IM_ASSERT(draw_list->VtxBuffer.Size == 0 || draw_list->_VtxWritePtr == draw_list->VtxBuffer.Data + draw_list->VtxBuffer.Size);
diff --git a/imgui.h b/imgui.h
index 45f3aa7..de4faf2 100644
--- a/imgui.h
+++ b/imgui.h
@@ -2061,6 +2061,7 @@
// NB: all primitives needs to be reserved via PrimReserve() beforehand!
IMGUI_API void ResetForNewFrame();
IMGUI_API void ClearFreeMemory();
+ IMGUI_API void PopUnusedDrawCmd();
IMGUI_API void PrimReserve(int idx_count, int vtx_count);
IMGUI_API void PrimUnreserve(int idx_count, int vtx_count);
IMGUI_API void PrimRect(const ImVec2& a, const ImVec2& b, ImU32 col); // Axis aligned rectangle (composed of two triangles)
diff --git a/imgui_draw.cpp b/imgui_draw.cpp
index 43daede..fb25fec 100644
--- a/imgui_draw.cpp
+++ b/imgui_draw.cpp
@@ -437,6 +437,17 @@
CmdBuffer.push_back(draw_cmd);
}
+// Pop trailing draw command (used before merging or presenting to user)
+// Note that this leaves the ImDrawList in a state unfit for further commands, as most code assume that CmdBuffer.Size > 0 && CmdBuffer.back().UserCallback == NULL
+void ImDrawList::PopUnusedDrawCmd()
+{
+ if (CmdBuffer.Size == 0)
+ return;
+ ImDrawCmd* curr_cmd = &CmdBuffer.Data[CmdBuffer.Size - 1];
+ if (curr_cmd->ElemCount == 0 && curr_cmd->UserCallback == NULL)
+ CmdBuffer.pop_back();
+}
+
void ImDrawList::AddCallback(ImDrawCallback callback, void* callback_data)
{
ImDrawCmd* curr_cmd = &CmdBuffer.Data[CmdBuffer.Size - 1];
@@ -1362,13 +1373,12 @@
void ImDrawListSplitter::Merge(ImDrawList* draw_list)
{
- // Note that we never use or rely on channels.Size because it is merely a buffer that we never shrink back to 0 to keep all sub-buffers ready for use.
+ // Note that we never use or rely on _Channels.Size because it is merely a buffer that we never shrink back to 0 to keep all sub-buffers ready for use.
if (_Count <= 1)
return;
SetCurrentChannel(draw_list, 0);
- if (draw_list->CmdBuffer.Size != 0 && draw_list->CmdBuffer.back().ElemCount == 0)
- draw_list->CmdBuffer.pop_back();
+ draw_list->PopUnusedDrawCmd();
// Calculate our final buffer sizes. Also fix the incorrect IdxOffset values in each command.
int new_cmd_buffer_count = 0;
@@ -1378,8 +1388,11 @@
for (int i = 1; i < _Count; i++)
{
ImDrawChannel& ch = _Channels[i];
+
+ // Equivalent of PopUnusedDrawCmd() for this channel's cmdbuffer and except we don't need to test for UserCallback.
if (ch._CmdBuffer.Size > 0 && ch._CmdBuffer.back().ElemCount == 0)
ch._CmdBuffer.pop_back();
+
if (ch._CmdBuffer.Size > 0 && last_cmd != NULL)
{
ImDrawCmd* next_cmd = &ch._CmdBuffer[0];
