Merge branch 'master' into viewport

# Conflicts:
#	imgui.cpp

imgui.cpp

@@ -53,6 +53,7 @@ CODE
 - ImGuiTextFilter
 - ImGuiTextBuffer
 - ImGuiListClipper
+- Render Helpers
 - Main Code (most of the code! lots of stuff, needs tidying up)
 - Tooltips
 - Popups
@@ -2075,6 +2076,226 @@ bool ImGuiListClipper::Step()
     return false;
 }
 
+//-----------------------------------------------------------------------------
+// RENDER HELPERS
+// Those [Internal] functions are a terrible mess - their signature and behavior will change.
+// Also see imgui_draw.cpp for some more which have been reworked to not rely on ImGui:: state.
+//-----------------------------------------------------------------------------
+
+const char* ImGui::FindRenderedTextEnd(const char* text, const char* text_end)
+{
+    const char* text_display_end = text;
+    if (!text_end)
+        text_end = (const char*)-1;
+
+    while (text_display_end < text_end && *text_display_end != '\0' && (text_display_end[0] != '#' || text_display_end[1] != '#'))
+        text_display_end++;
+    return text_display_end;
+}
+
+// Internal ImGui functions to render text
+// RenderText***() functions calls ImDrawList::AddText() calls ImBitmapFont::RenderText()
+void ImGui::RenderText(ImVec2 pos, const char* text, const char* text_end, bool hide_text_after_hash)
+{
+    ImGuiContext& g = *GImGui;
+    ImGuiWindow* window = g.CurrentWindow;
+
+    // Hide anything after a '##' string
+    const char* text_display_end;
+    if (hide_text_after_hash)
+    {
+        text_display_end = FindRenderedTextEnd(text, text_end);
+    }
+    else
+    {
+        if (!text_end)
+            text_end = text + strlen(text); // FIXME-OPT
+        text_display_end = text_end;
+    }
+
+    if (text != text_display_end)
+    {
+        window->DrawList->AddText(g.Font, g.FontSize, pos, GetColorU32(ImGuiCol_Text), text, text_display_end);
+        if (g.LogEnabled)
+            LogRenderedText(&pos, text, text_display_end);
+    }
+}
+
+void ImGui::RenderTextWrapped(ImVec2 pos, const char* text, const char* text_end, float wrap_width)
+{
+    ImGuiContext& g = *GImGui;
+    ImGuiWindow* window = g.CurrentWindow;
+
+    if (!text_end)
+        text_end = text + strlen(text); // FIXME-OPT
+
+    if (text != text_end)
+    {
+        window->DrawList->AddText(g.Font, g.FontSize, pos, GetColorU32(ImGuiCol_Text), text, text_end, wrap_width);
+        if (g.LogEnabled)
+            LogRenderedText(&pos, text, text_end);
+    }
+}
+
+// Default clip_rect uses (pos_min,pos_max)
+// Handle clipping on CPU immediately (vs typically let the GPU clip the triangles that are overlapping the clipping rectangle edges)
+void ImGui::RenderTextClipped(const ImVec2& pos_min, const ImVec2& pos_max, const char* text, const char* text_end, const ImVec2* text_size_if_known, const ImVec2& align, const ImRect* clip_rect)
+{
+    // Hide anything after a '##' string
+    const char* text_display_end = FindRenderedTextEnd(text, text_end);
+    const int text_len = (int)(text_display_end - text);
+    if (text_len == 0)
+        return;
+
+    ImGuiContext& g = *GImGui;
+    ImGuiWindow* window = g.CurrentWindow;
+
+    // Perform CPU side clipping for single clipped element to avoid using scissor state
+    ImVec2 pos = pos_min;
+    const ImVec2 text_size = text_size_if_known ? *text_size_if_known : CalcTextSize(text, text_display_end, false, 0.0f);
+
+    const ImVec2* clip_min = clip_rect ? &clip_rect->Min : &pos_min;
+    const ImVec2* clip_max = clip_rect ? &clip_rect->Max : &pos_max;
+    bool need_clipping = (pos.x + text_size.x >= clip_max->x) || (pos.y + text_size.y >= clip_max->y);
+    if (clip_rect) // If we had no explicit clipping rectangle then pos==clip_min
+        need_clipping |= (pos.x < clip_min->x) || (pos.y < clip_min->y);
+
+    // Align whole block. We should defer that to the better rendering function when we'll have support for individual line alignment.
+    if (align.x > 0.0f) pos.x = ImMax(pos.x, pos.x + (pos_max.x - pos.x - text_size.x) * align.x);
+    if (align.y > 0.0f) pos.y = ImMax(pos.y, pos.y + (pos_max.y - pos.y - text_size.y) * align.y);
+
+    // Render
+    if (need_clipping)
+    {
+        ImVec4 fine_clip_rect(clip_min->x, clip_min->y, clip_max->x, clip_max->y);
+        window->DrawList->AddText(g.Font, g.FontSize, pos, GetColorU32(ImGuiCol_Text), text, text_display_end, 0.0f, &fine_clip_rect);
+    }
+    else
+    {
+        window->DrawList->AddText(g.Font, g.FontSize, pos, GetColorU32(ImGuiCol_Text), text, text_display_end, 0.0f, NULL);
+    }
+    if (g.LogEnabled)
+        LogRenderedText(&pos, text, text_display_end);
+}
+
+// Render a rectangle shaped with optional rounding and borders
+void ImGui::RenderFrame(ImVec2 p_min, ImVec2 p_max, ImU32 fill_col, bool border, float rounding)
+{
+    ImGuiContext& g = *GImGui;
+    ImGuiWindow* window = g.CurrentWindow;
+    window->DrawList->AddRectFilled(p_min, p_max, fill_col, rounding);
+    const float border_size = g.Style.FrameBorderSize;
+    if (border && border_size > 0.0f)
+    {
+        window->DrawList->AddRect(p_min+ImVec2(1,1), p_max+ImVec2(1,1), GetColorU32(ImGuiCol_BorderShadow), rounding, ImDrawCornerFlags_All, border_size);
+        window->DrawList->AddRect(p_min, p_max, GetColorU32(ImGuiCol_Border), rounding, ImDrawCornerFlags_All, border_size);
+    }
+}
+
+void ImGui::RenderFrameBorder(ImVec2 p_min, ImVec2 p_max, float rounding)
+{
+    ImGuiContext& g = *GImGui;
+    ImGuiWindow* window = g.CurrentWindow;
+    const float border_size = g.Style.FrameBorderSize;
+    if (border_size > 0.0f)
+    {
+        window->DrawList->AddRect(p_min+ImVec2(1,1), p_max+ImVec2(1,1), GetColorU32(ImGuiCol_BorderShadow), rounding, ImDrawCornerFlags_All, border_size);
+        window->DrawList->AddRect(p_min, p_max, GetColorU32(ImGuiCol_Border), rounding, ImDrawCornerFlags_All, border_size);
+    }
+}
+
+// Render an arrow aimed to be aligned with text (p_min is a position in the same space text would be positioned). To e.g. denote expanded/collapsed state
+void ImGui::RenderArrow(ImVec2 p_min, ImGuiDir dir, float scale)
+{
+    ImGuiContext& g = *GImGui;
+
+    const float h = g.FontSize * 1.00f;
+    float r = h * 0.40f * scale;
+    ImVec2 center = p_min + ImVec2(h * 0.50f, h * 0.50f * scale);
+
+    ImVec2 a, b, c;
+    switch (dir)
+    {
+    case ImGuiDir_Up:
+    case ImGuiDir_Down:
+        if (dir == ImGuiDir_Up) r = -r;
+        a = ImVec2(+0.000f,+0.750f) * r;
+        b = ImVec2(-0.866f,-0.750f) * r;
+        c = ImVec2(+0.866f,-0.750f) * r;
+        break;
+    case ImGuiDir_Left:
+    case ImGuiDir_Right:
+        if (dir == ImGuiDir_Left) r = -r;
+        a = ImVec2(+0.750f,+0.000f) * r;
+        b = ImVec2(-0.750f,+0.866f) * r;
+        c = ImVec2(-0.750f,-0.866f) * r;
+        break;
+    case ImGuiDir_None:
+    case ImGuiDir_COUNT:
+        IM_ASSERT(0);
+        break;
+    }
+
+    g.CurrentWindow->DrawList->AddTriangleFilled(center + a, center + b, center + c, GetColorU32(ImGuiCol_Text));
+}
+
+void ImGui::RenderBullet(ImVec2 pos)
+{
+    ImGuiContext& g = *GImGui;
+    ImGuiWindow* window = g.CurrentWindow;
+    window->DrawList->AddCircleFilled(pos, g.FontSize*0.20f, GetColorU32(ImGuiCol_Text), 8);
+}
+
+void ImGui::RenderCheckMark(ImVec2 pos, ImU32 col, float sz)
+{
+    ImGuiContext& g = *GImGui;
+    ImGuiWindow* window = g.CurrentWindow;
+
+    float thickness = ImMax(sz / 5.0f, 1.0f);
+    sz -= thickness*0.5f;
+    pos += ImVec2(thickness*0.25f, thickness*0.25f);
+
+    float third = sz / 3.0f;
+    float bx = pos.x + third;
+    float by = pos.y + sz - third*0.5f;
+    window->DrawList->PathLineTo(ImVec2(bx - third, by - third));
+    window->DrawList->PathLineTo(ImVec2(bx, by));
+    window->DrawList->PathLineTo(ImVec2(bx + third*2, by - third*2));
+    window->DrawList->PathStroke(col, false, thickness);
+}
+
+void ImGui::RenderNavHighlight(const ImRect& bb, ImGuiID id, ImGuiNavHighlightFlags flags)
+{
+    ImGuiContext& g = *GImGui;
+    if (id != g.NavId)
+        return;
+    if (g.NavDisableHighlight && !(flags & ImGuiNavHighlightFlags_AlwaysDraw))
+        return;
+    ImGuiWindow* window = ImGui::GetCurrentWindow();
+    if (window->DC.NavHideHighlightOneFrame)
+        return;
+
+    float rounding = (flags & ImGuiNavHighlightFlags_NoRounding) ? 0.0f : g.Style.FrameRounding;
+    ImRect display_rect = bb;
+    display_rect.ClipWith(window->ClipRect);
+    if (flags & ImGuiNavHighlightFlags_TypeDefault)
+    {
+        const float THICKNESS = 2.0f;
+        const float DISTANCE = 3.0f + THICKNESS * 0.5f;
+        display_rect.Expand(ImVec2(DISTANCE,DISTANCE));
+        bool fully_visible = window->ClipRect.Contains(display_rect);
+        if (!fully_visible)
+            window->DrawList->PushClipRect(display_rect.Min, display_rect.Max);
+        window->DrawList->AddRect(display_rect.Min + ImVec2(THICKNESS*0.5f,THICKNESS*0.5f), display_rect.Max - ImVec2(THICKNESS*0.5f,THICKNESS*0.5f), GetColorU32(ImGuiCol_NavHighlight), rounding, ImDrawCornerFlags_All, THICKNESS);
+        if (!fully_visible)
+            window->DrawList->PopClipRect();
+    }
+    if (flags & ImGuiNavHighlightFlags_TypeThin)
+    {
+        window->DrawList->AddRect(display_rect.Min, display_rect.Max, GetColorU32(ImGuiCol_NavHighlight), rounding, ~0, 1.0f);
+    }
+}
+
 //-----------------------------------------------------------------------------
 // MAIN CODE
 // (this category is still too large and badly ordered, needs some tidying up)
@@ -3463,326 +3684,112 @@ void ImGui::EndFrame()
                 // This is where we can trim the popup stack.
                 ImGuiWindow* modal = GetFrontMostPopupModal();
                 bool hovered_window_above_modal = false;
-                if (modal == NULL)
-                    hovered_window_above_modal = true;
-                for (int i = g.Windows.Size - 1; i >= 0 && hovered_window_above_modal == false; i--)
-                {
-                    ImGuiWindow* window = g.Windows[i];
-                    if (window == modal)
-                        break;
-                    if (window == g.HoveredWindow)
-                        hovered_window_above_modal = true;
-                }
-                ClosePopupsOverWindow(hovered_window_above_modal ? g.HoveredWindow : modal);
-            }
-        }
-    }
-
-    // Update user-facing viewport list
-    g.PlatformIO.MainViewport = g.Viewports[0];
-    g.PlatformIO.Viewports.resize(0);
-    for (int i = 0; i < g.Viewports.Size; i++)
-    {
-        ImGuiViewportP* viewport = g.Viewports[i];
-        if (viewport->LastFrameActive < g.FrameCount || viewport->Size.x <= 0.0f || viewport->Size.y <= 0.0f)
-            continue;
-        if (viewport->Window && !IsWindowActiveAndVisible(viewport->Window))
-            continue;
-        if (i > 0)
-            IM_ASSERT(viewport->Window != NULL);
-        g.PlatformIO.Viewports.push_back(viewport);
-    }
-
-    // Sort the window list so that all child windows are after their parent
-    // We cannot do that on FocusWindow() because childs may not exist yet
-    g.WindowsSortBuffer.resize(0);
-    g.WindowsSortBuffer.reserve(g.Windows.Size);
-    for (int i = 0; i != g.Windows.Size; i++)
-    {
-        ImGuiWindow* window = g.Windows[i];
-        if (window->Active && (window->Flags & ImGuiWindowFlags_ChildWindow))       // if a child is active its parent will add it
-            continue;
-        AddWindowToSortedBuffer(&g.WindowsSortBuffer, window);
-    }
-
-    IM_ASSERT(g.Windows.Size == g.WindowsSortBuffer.Size);  // we done something wrong
-    g.Windows.swap(g.WindowsSortBuffer);
-    g.IO.MetricsActiveWindows = g.WindowsActiveCount;
-
-    // Unlock font atlas
-    g.IO.Fonts->Locked = false;
-
-    // Clear Input data for next frame
-    g.IO.MouseWheel = g.IO.MouseWheelH = 0.0f;
-    memset(g.IO.InputCharacters, 0, sizeof(g.IO.InputCharacters));
-    memset(g.IO.NavInputs, 0, sizeof(g.IO.NavInputs));
-
-    g.FrameScopeActive = false;
-    g.FrameCountEnded = g.FrameCount;
-}
-
-void ImGui::Render()
-{
-    ImGuiContext& g = *GImGui;
-    IM_ASSERT(g.Initialized);
-
-    if (g.FrameCountEnded != g.FrameCount)
-        ImGui::EndFrame();
-    g.FrameCountRendered = g.FrameCount;
-
-    // Gather ImDrawList to render (for each active window)
-    g.IO.MetricsRenderVertices = g.IO.MetricsRenderIndices = g.IO.MetricsRenderWindows = 0;
-    for (int n = 0; n != g.Viewports.Size; n++)
-        g.Viewports[n]->DrawDataBuilder.Clear();
-    ImGuiWindow* windows_to_render_front_most[2];
-    windows_to_render_front_most[0] = (g.NavWindowingTarget && !(g.NavWindowingTarget->Flags & ImGuiWindowFlags_NoBringToFrontOnFocus)) ? g.NavWindowingTarget->RootWindow : NULL;
-    windows_to_render_front_most[1] = g.NavWindowingTarget ? g.NavWindowingList : NULL;
-    for (int n = 0; n != g.Windows.Size; n++)
-    {
-        ImGuiWindow* window = g.Windows[n];
-        if (IsWindowActiveAndVisible(window) && (window->Flags & ImGuiWindowFlags_ChildWindow) == 0 && window != windows_to_render_front_most[0] && window != windows_to_render_front_most[1])
-            AddRootWindowToDrawData(window);
-    }
-    for (int n = 0; n < IM_ARRAYSIZE(windows_to_render_front_most); n++)
-        if (windows_to_render_front_most[n] && IsWindowActiveAndVisible(windows_to_render_front_most[n])) // NavWindowingTarget is always temporarily displayed as the front-most window
-            AddRootWindowToDrawData(windows_to_render_front_most[n]);
-
-    // Draw software mouse cursor if requested
-    if (g.IO.MouseDrawCursor)
-        RenderMouseCursor(g.IO.MousePos, g.Style.MouseCursorScale, g.MouseCursor);
-
-    // Setup ImDrawData structures for end-user
-    g.IO.MetricsRenderVertices = g.IO.MetricsRenderIndices = 0;
-    for (int n = 0; n < g.Viewports.Size; n++)
-    {
-        ImGuiViewportP* viewport = g.Viewports[n];
-        viewport->DrawDataBuilder.FlattenIntoSingleLayer();
-        if (viewport->OverlayDrawList != NULL)
-            AddDrawListToDrawData(&viewport->DrawDataBuilder.Layers[0], GetOverlayDrawList(viewport));
-        SetupViewportDrawData(viewport, &viewport->DrawDataBuilder.Layers[0]);
-        g.IO.MetricsRenderVertices += viewport->DrawData->TotalVtxCount;
-        g.IO.MetricsRenderIndices += viewport->DrawData->TotalIdxCount;
-    }
-
-    // Render. If user hasn't set a callback then they may retrieve the draw data via GetDrawData()
-#ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
-    if (g.Viewports[0]->DrawData->CmdListsCount > 0 && g.IO.RenderDrawListsFn != NULL)
-        g.IO.RenderDrawListsFn(g.Viewports[0]->DrawData);
-#endif
-}
-
-const char* ImGui::FindRenderedTextEnd(const char* text, const char* text_end)
-{
-    const char* text_display_end = text;
-    if (!text_end)
-        text_end = (const char*)-1;
-
-    while (text_display_end < text_end && *text_display_end != '\0' && (text_display_end[0] != '#' || text_display_end[1] != '#'))
-        text_display_end++;
-    return text_display_end;
-}
-
-// Internal ImGui functions to render text
-// RenderText***() functions calls ImDrawList::AddText() calls ImBitmapFont::RenderText()
-void ImGui::RenderText(ImVec2 pos, const char* text, const char* text_end, bool hide_text_after_hash)
-{
-    ImGuiContext& g = *GImGui;
-    ImGuiWindow* window = g.CurrentWindow;
-
-    // Hide anything after a '##' string
-    const char* text_display_end;
-    if (hide_text_after_hash)
-    {
-        text_display_end = FindRenderedTextEnd(text, text_end);
-    }
-    else
-    {
-        if (!text_end)
-            text_end = text + strlen(text); // FIXME-OPT
-        text_display_end = text_end;
-    }
-
-    if (text != text_display_end)
-    {
-        window->DrawList->AddText(g.Font, g.FontSize, pos, GetColorU32(ImGuiCol_Text), text, text_display_end);
-        if (g.LogEnabled)
-            LogRenderedText(&pos, text, text_display_end);
-    }
-}
-
-void ImGui::RenderTextWrapped(ImVec2 pos, const char* text, const char* text_end, float wrap_width)
-{
-    ImGuiContext& g = *GImGui;
-    ImGuiWindow* window = g.CurrentWindow;
-
-    if (!text_end)
-        text_end = text + strlen(text); // FIXME-OPT
-
-    if (text != text_end)
-    {
-        window->DrawList->AddText(g.Font, g.FontSize, pos, GetColorU32(ImGuiCol_Text), text, text_end, wrap_width);
-        if (g.LogEnabled)
-            LogRenderedText(&pos, text, text_end);
-    }
-}
-
-// Default clip_rect uses (pos_min,pos_max)
-// Handle clipping on CPU immediately (vs typically let the GPU clip the triangles that are overlapping the clipping rectangle edges)
-void ImGui::RenderTextClipped(const ImVec2& pos_min, const ImVec2& pos_max, const char* text, const char* text_end, const ImVec2* text_size_if_known, const ImVec2& align, const ImRect* clip_rect)
-{
-    // Hide anything after a '##' string
-    const char* text_display_end = FindRenderedTextEnd(text, text_end);
-    const int text_len = (int)(text_display_end - text);
-    if (text_len == 0)
-        return;
-
-    ImGuiContext& g = *GImGui;
-    ImGuiWindow* window = g.CurrentWindow;
-
-    // Perform CPU side clipping for single clipped element to avoid using scissor state
-    ImVec2 pos = pos_min;
-    const ImVec2 text_size = text_size_if_known ? *text_size_if_known : CalcTextSize(text, text_display_end, false, 0.0f);
-
-    const ImVec2* clip_min = clip_rect ? &clip_rect->Min : &pos_min;
-    const ImVec2* clip_max = clip_rect ? &clip_rect->Max : &pos_max;
-    bool need_clipping = (pos.x + text_size.x >= clip_max->x) || (pos.y + text_size.y >= clip_max->y);
-    if (clip_rect) // If we had no explicit clipping rectangle then pos==clip_min
-        need_clipping |= (pos.x < clip_min->x) || (pos.y < clip_min->y);
-
-    // Align whole block. We should defer that to the better rendering function when we'll have support for individual line alignment.
-    if (align.x > 0.0f) pos.x = ImMax(pos.x, pos.x + (pos_max.x - pos.x - text_size.x) * align.x);
-    if (align.y > 0.0f) pos.y = ImMax(pos.y, pos.y + (pos_max.y - pos.y - text_size.y) * align.y);
-
-    // Render
-    if (need_clipping)
-    {
-        ImVec4 fine_clip_rect(clip_min->x, clip_min->y, clip_max->x, clip_max->y);
-        window->DrawList->AddText(g.Font, g.FontSize, pos, GetColorU32(ImGuiCol_Text), text, text_display_end, 0.0f, &fine_clip_rect);
-    }
-    else
-    {
-        window->DrawList->AddText(g.Font, g.FontSize, pos, GetColorU32(ImGuiCol_Text), text, text_display_end, 0.0f, NULL);
-    }
-    if (g.LogEnabled)
-        LogRenderedText(&pos, text, text_display_end);
-}
-
-// Render a rectangle shaped with optional rounding and borders
-void ImGui::RenderFrame(ImVec2 p_min, ImVec2 p_max, ImU32 fill_col, bool border, float rounding)
-{
-    ImGuiContext& g = *GImGui;
-    ImGuiWindow* window = g.CurrentWindow;
-    window->DrawList->AddRectFilled(p_min, p_max, fill_col, rounding);
-    const float border_size = g.Style.FrameBorderSize;
-    if (border && border_size > 0.0f)
-    {
-        window->DrawList->AddRect(p_min+ImVec2(1,1), p_max+ImVec2(1,1), GetColorU32(ImGuiCol_BorderShadow), rounding, ImDrawCornerFlags_All, border_size);
-        window->DrawList->AddRect(p_min, p_max, GetColorU32(ImGuiCol_Border), rounding, ImDrawCornerFlags_All, border_size);
+                if (modal == NULL)
+                    hovered_window_above_modal = true;
+                for (int i = g.Windows.Size - 1; i >= 0 && hovered_window_above_modal == false; i--)
+                {
+                    ImGuiWindow* window = g.Windows[i];
+                    if (window == modal)
+                        break;
+                    if (window == g.HoveredWindow)
+                        hovered_window_above_modal = true;
+                }
+                ClosePopupsOverWindow(hovered_window_above_modal ? g.HoveredWindow : modal);
+            }
+        }
     }
-}
 
-void ImGui::RenderFrameBorder(ImVec2 p_min, ImVec2 p_max, float rounding)
-{
-    ImGuiContext& g = *GImGui;
-    ImGuiWindow* window = g.CurrentWindow;
-    const float border_size = g.Style.FrameBorderSize;
-    if (border_size > 0.0f)
+    // Update user-facing viewport list
+    g.PlatformIO.MainViewport = g.Viewports[0];
+    g.PlatformIO.Viewports.resize(0);
+    for (int i = 0; i < g.Viewports.Size; i++)
     {
-        window->DrawList->AddRect(p_min+ImVec2(1,1), p_max+ImVec2(1,1), GetColorU32(ImGuiCol_BorderShadow), rounding, ImDrawCornerFlags_All, border_size);
-        window->DrawList->AddRect(p_min, p_max, GetColorU32(ImGuiCol_Border), rounding, ImDrawCornerFlags_All, border_size);
+        ImGuiViewportP* viewport = g.Viewports[i];
+        if (viewport->LastFrameActive < g.FrameCount || viewport->Size.x <= 0.0f || viewport->Size.y <= 0.0f)
+            continue;
+        if (viewport->Window && !IsWindowActiveAndVisible(viewport->Window))
+            continue;
+        if (i > 0)
+            IM_ASSERT(viewport->Window != NULL);
+        g.PlatformIO.Viewports.push_back(viewport);
     }
-}
-
-// Render an arrow aimed to be aligned with text (p_min is a position in the same space text would be positioned). To e.g. denote expanded/collapsed state
-void ImGui::RenderArrow(ImVec2 p_min, ImGuiDir dir, float scale)
-{
-    ImGuiContext& g = *GImGui;
 
-    const float h = g.FontSize * 1.00f;
-    float r = h * 0.40f * scale;
-    ImVec2 center = p_min + ImVec2(h * 0.50f, h * 0.50f * scale);
-
-    ImVec2 a, b, c;
-    switch (dir)
+    // Sort the window list so that all child windows are after their parent
+    // We cannot do that on FocusWindow() because childs may not exist yet
+    g.WindowsSortBuffer.resize(0);
+    g.WindowsSortBuffer.reserve(g.Windows.Size);
+    for (int i = 0; i != g.Windows.Size; i++)
     {
-    case ImGuiDir_Up:
-    case ImGuiDir_Down:
-        if (dir == ImGuiDir_Up) r = -r;
-        a = ImVec2(+0.000f,+0.750f) * r;
-        b = ImVec2(-0.866f,-0.750f) * r;
-        c = ImVec2(+0.866f,-0.750f) * r;
-        break;
-    case ImGuiDir_Left:
-    case ImGuiDir_Right:
-        if (dir == ImGuiDir_Left) r = -r;
-        a = ImVec2(+0.750f,+0.000f) * r;
-        b = ImVec2(-0.750f,+0.866f) * r;
-        c = ImVec2(-0.750f,-0.866f) * r;
-        break;
-    case ImGuiDir_None:
-    case ImGuiDir_COUNT:
-        IM_ASSERT(0);
-        break;
+        ImGuiWindow* window = g.Windows[i];
+        if (window->Active && (window->Flags & ImGuiWindowFlags_ChildWindow))       // if a child is active its parent will add it
+            continue;
+        AddWindowToSortedBuffer(&g.WindowsSortBuffer, window);
     }
 
-    g.CurrentWindow->DrawList->AddTriangleFilled(center + a, center + b, center + c, GetColorU32(ImGuiCol_Text));
-}
-
-void ImGui::RenderBullet(ImVec2 pos)
-{
-    ImGuiContext& g = *GImGui;
-    ImGuiWindow* window = g.CurrentWindow;
-    window->DrawList->AddCircleFilled(pos, g.FontSize*0.20f, GetColorU32(ImGuiCol_Text), 8);
-}
+    IM_ASSERT(g.Windows.Size == g.WindowsSortBuffer.Size);  // we done something wrong
+    g.Windows.swap(g.WindowsSortBuffer);
+    g.IO.MetricsActiveWindows = g.WindowsActiveCount;
 
-void ImGui::RenderCheckMark(ImVec2 pos, ImU32 col, float sz)
-{
-    ImGuiContext& g = *GImGui;
-    ImGuiWindow* window = g.CurrentWindow;
+    // Unlock font atlas
+    g.IO.Fonts->Locked = false;
 
-    float thickness = ImMax(sz / 5.0f, 1.0f);
-    sz -= thickness*0.5f;
-    pos += ImVec2(thickness*0.25f, thickness*0.25f);
+    // Clear Input data for next frame
+    g.IO.MouseWheel = g.IO.MouseWheelH = 0.0f;
+    memset(g.IO.InputCharacters, 0, sizeof(g.IO.InputCharacters));
+    memset(g.IO.NavInputs, 0, sizeof(g.IO.NavInputs));
 
-    float third = sz / 3.0f;
-    float bx = pos.x + third;
-    float by = pos.y + sz - third*0.5f;
-    window->DrawList->PathLineTo(ImVec2(bx - third, by - third));
-    window->DrawList->PathLineTo(ImVec2(bx, by));
-    window->DrawList->PathLineTo(ImVec2(bx + third*2, by - third*2));
-    window->DrawList->PathStroke(col, false, thickness);
+    g.FrameScopeActive = false;
+    g.FrameCountEnded = g.FrameCount;
 }
 
-void ImGui::RenderNavHighlight(const ImRect& bb, ImGuiID id, ImGuiNavHighlightFlags flags)
+void ImGui::Render()
 {
     ImGuiContext& g = *GImGui;
-    if (id != g.NavId)
-        return;
-    if (g.NavDisableHighlight && !(flags & ImGuiNavHighlightFlags_AlwaysDraw))
-        return;
-    ImGuiWindow* window = ImGui::GetCurrentWindow();
-    if (window->DC.NavHideHighlightOneFrame)
-        return;
+    IM_ASSERT(g.Initialized);
 
-    float rounding = (flags & ImGuiNavHighlightFlags_NoRounding) ? 0.0f : g.Style.FrameRounding;
-    ImRect display_rect = bb;
-    display_rect.ClipWith(window->ClipRect);
-    if (flags & ImGuiNavHighlightFlags_TypeDefault)
+    if (g.FrameCountEnded != g.FrameCount)
+        ImGui::EndFrame();
+    g.FrameCountRendered = g.FrameCount;
+
+    // Gather ImDrawList to render (for each active window)
+    g.IO.MetricsRenderVertices = g.IO.MetricsRenderIndices = g.IO.MetricsRenderWindows = 0;
+    for (int n = 0; n != g.Viewports.Size; n++)
+        g.Viewports[n]->DrawDataBuilder.Clear();
+    ImGuiWindow* windows_to_render_front_most[2];
+    windows_to_render_front_most[0] = (g.NavWindowingTarget && !(g.NavWindowingTarget->Flags & ImGuiWindowFlags_NoBringToFrontOnFocus)) ? g.NavWindowingTarget->RootWindow : NULL;
+    windows_to_render_front_most[1] = g.NavWindowingTarget ? g.NavWindowingList : NULL;
+    for (int n = 0; n != g.Windows.Size; n++)
     {
-        const float THICKNESS = 2.0f;
-        const float DISTANCE = 3.0f + THICKNESS * 0.5f;
-        display_rect.Expand(ImVec2(DISTANCE,DISTANCE));
-        bool fully_visible = window->ClipRect.Contains(display_rect);
-        if (!fully_visible)
-            window->DrawList->PushClipRect(display_rect.Min, display_rect.Max);
-        window->DrawList->AddRect(display_rect.Min + ImVec2(THICKNESS*0.5f,THICKNESS*0.5f), display_rect.Max - ImVec2(THICKNESS*0.5f,THICKNESS*0.5f), GetColorU32(ImGuiCol_NavHighlight), rounding, ImDrawCornerFlags_All, THICKNESS);
-        if (!fully_visible)
-            window->DrawList->PopClipRect();
+        ImGuiWindow* window = g.Windows[n];
+        if (IsWindowActiveAndVisible(window) && (window->Flags & ImGuiWindowFlags_ChildWindow) == 0 && window != windows_to_render_front_most[0] && window != windows_to_render_front_most[1])
+            AddRootWindowToDrawData(window);
     }
-    if (flags & ImGuiNavHighlightFlags_TypeThin)
+    for (int n = 0; n < IM_ARRAYSIZE(windows_to_render_front_most); n++)
+        if (windows_to_render_front_most[n] && IsWindowActiveAndVisible(windows_to_render_front_most[n])) // NavWindowingTarget is always temporarily displayed as the front-most window
+            AddRootWindowToDrawData(windows_to_render_front_most[n]);
+
+    // Draw software mouse cursor if requested
+    if (g.IO.MouseDrawCursor)
+        RenderMouseCursor(g.IO.MousePos, g.Style.MouseCursorScale, g.MouseCursor);
+
+    // Setup ImDrawData structures for end-user
+    g.IO.MetricsRenderVertices = g.IO.MetricsRenderIndices = 0;
+    for (int n = 0; n < g.Viewports.Size; n++)
     {
-        window->DrawList->AddRect(display_rect.Min, display_rect.Max, GetColorU32(ImGuiCol_NavHighlight), rounding, ~0, 1.0f);
+        ImGuiViewportP* viewport = g.Viewports[n];
+        viewport->DrawDataBuilder.FlattenIntoSingleLayer();
+        if (viewport->OverlayDrawList != NULL)
+            AddDrawListToDrawData(&viewport->DrawDataBuilder.Layers[0], GetOverlayDrawList(viewport));
+        SetupViewportDrawData(viewport, &viewport->DrawDataBuilder.Layers[0]);
+        g.IO.MetricsRenderVertices += viewport->DrawData->TotalVtxCount;
+        g.IO.MetricsRenderIndices += viewport->DrawData->TotalIdxCount;
     }
+
+    // Render. If user hasn't set a callback then they may retrieve the draw data via GetDrawData()
+#ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
+    if (g.Viewports[0]->DrawData->CmdListsCount > 0 && g.IO.RenderDrawListsFn != NULL)
+        g.IO.RenderDrawListsFn(g.Viewports[0]->DrawData);
+#endif
 }
 
 // Calculate text size. Text can be multi-line. Optionally ignore text after a ## marker.
@@ -4558,7 +4565,7 @@ const ImGuiResizeGripDef resize_grip_def[4] =
     { ImVec2(1,0), ImVec2(-1,+1), 9,12 }, // Upper right
 };
 
-static ImRect GetBorderRect(ImGuiWindow* window, int border_n, float perp_padding, float thickness)
+static ImRect GetResizeBorderRect(ImGuiWindow* window, int border_n, float perp_padding, float thickness)
 {
     ImRect rect = window->Rect();
     if (thickness == 0.0f) rect.Max -= ImVec2(1,1);
@@ -4622,7 +4629,7 @@ static void ImGui::UpdateManualResize(ImGuiWindow* window, const ImVec2& size_au
         const float BORDER_SIZE = 5.0f;          // FIXME: Only works _inside_ window because of HoveredWindow check.
         const float BORDER_APPEAR_TIMER = 0.05f; // Reduce visual noise
         bool hovered, held;
-        ImRect border_rect = GetBorderRect(window, border_n, grip_hover_size, BORDER_SIZE);
+        ImRect border_rect = GetResizeBorderRect(window, border_n, grip_hover_size, BORDER_SIZE);
         ButtonBehavior(border_rect, window->GetID((void*)(intptr_t)(border_n + 4)), &hovered, &held, ImGuiButtonFlags_FlattenChildren);
         if ((hovered && g.HoveredIdTimer > BORDER_APPEAR_TIMER) || held)
         {
@@ -5187,7 +5194,7 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
                 window->DrawList->AddRect(window->Pos, window->Pos + window->Size, GetColorU32(ImGuiCol_Border), window_rounding, ImDrawCornerFlags_All, window_border_size);
             if (border_held != -1)
             {
-                ImRect border = GetBorderRect(window, border_held, grip_draw_size, 0.0f);
+                ImRect border = GetResizeBorderRect(window, border_held, grip_draw_size, 0.0f);
                 window->DrawList->AddLine(border.Min, border.Max, GetColorU32(ImGuiCol_SeparatorActive), ImMax(1.0f, window_border_size));
             }
             if (style.FrameBorderSize > 0 && !(flags & ImGuiWindowFlags_NoTitleBar))
@@ -6383,17 +6390,6 @@ ImGuiStorage* ImGui::GetStateStorage()
     return window->DC.StateStorage;
 }
 
-void ImGui::AlignTextToFramePadding()
-{
-    ImGuiWindow* window = GetCurrentWindow();
-    if (window->SkipItems)
-        return;
-
-    ImGuiContext& g = *GImGui;
-    window->DC.CurrentLineSize.y = ImMax(window->DC.CurrentLineSize.y, g.FontSize + g.Style.FramePadding.y * 2);
-    window->DC.CurrentLineTextBaseOffset = ImMax(window->DC.CurrentLineTextBaseOffset, g.Style.FramePadding.y);
-}
-
 void ImGui::PushID(const char* str_id)
 {
     ImGuiWindow* window = GetCurrentWindowRead();
@@ -6440,149 +6436,6 @@ ImGuiID ImGui::GetID(const void* ptr_id)
     return GImGui->CurrentWindow->GetID(ptr_id);
 }
 
-// Horizontal/vertical separating line
-void ImGui::Separator()
-{
-    ImGuiWindow* window = GetCurrentWindow();
-    if (window->SkipItems)
-        return;
-    ImGuiContext& g = *GImGui;
-
-    // Those flags should eventually be overridable by the user
-    ImGuiSeparatorFlags flags = (window->DC.LayoutType == ImGuiLayoutType_Horizontal) ? ImGuiSeparatorFlags_Vertical : ImGuiSeparatorFlags_Horizontal;
-    IM_ASSERT(ImIsPowerOfTwo((int)(flags & (ImGuiSeparatorFlags_Horizontal | ImGuiSeparatorFlags_Vertical))));   // Check that only 1 option is selected
-    if (flags & ImGuiSeparatorFlags_Vertical)
-    {
-        VerticalSeparator();
-        return;
-    }
-
-    // Horizontal Separator
-    if (window->DC.ColumnsSet)
-        PopClipRect();
-
-    float x1 = window->Pos.x;
-    float x2 = window->Pos.x + window->Size.x;
-    if (!window->DC.GroupStack.empty())
-        x1 += window->DC.Indent.x;
-
-    const ImRect bb(ImVec2(x1, window->DC.CursorPos.y), ImVec2(x2, window->DC.CursorPos.y+1.0f));
-    ItemSize(ImVec2(0.0f, 0.0f)); // NB: we don't provide our width so that it doesn't get feed back into AutoFit, we don't provide height to not alter layout.
-    if (!ItemAdd(bb, 0))
-    {
-        if (window->DC.ColumnsSet)
-            PushColumnClipRect();
-        return;
-    }
-
-    window->DrawList->AddLine(bb.Min, ImVec2(bb.Max.x,bb.Min.y), GetColorU32(ImGuiCol_Separator));
-
-    if (g.LogEnabled)
-        LogRenderedText(NULL, IM_NEWLINE "--------------------------------");
-
-    if (window->DC.ColumnsSet)
-    {
-        PushColumnClipRect();
-        window->DC.ColumnsSet->LineMinY = window->DC.CursorPos.y;
-    }
-}
-
-void ImGui::VerticalSeparator()
-{
-    ImGuiWindow* window = GetCurrentWindow();
-    if (window->SkipItems)
-        return;
-    ImGuiContext& g = *GImGui;
-
-    float y1 = window->DC.CursorPos.y;
-    float y2 = window->DC.CursorPos.y + window->DC.CurrentLineSize.y;
-    const ImRect bb(ImVec2(window->DC.CursorPos.x, y1), ImVec2(window->DC.CursorPos.x + 1.0f, y2));
-    ItemSize(ImVec2(bb.GetWidth(), 0.0f));
-    if (!ItemAdd(bb, 0))
-        return;
-
-    window->DrawList->AddLine(ImVec2(bb.Min.x, bb.Min.y), ImVec2(bb.Min.x, bb.Max.y), GetColorU32(ImGuiCol_Separator));
-    if (g.LogEnabled)
-        LogText(" |");
-}
-
-// Using 'hover_visibility_delay' allows us to hide the highlight and mouse cursor for a short time, which can be convenient to reduce visual noise.
-bool ImGui::SplitterBehavior(const ImRect& bb, ImGuiID id, ImGuiAxis axis, float* size1, float* size2, float min_size1, float min_size2, float hover_extend, float hover_visibility_delay)
-{
-    ImGuiContext& g = *GImGui;
-    ImGuiWindow* window = g.CurrentWindow;
-
-    const ImGuiItemFlags item_flags_backup = window->DC.ItemFlags;
-    window->DC.ItemFlags |= ImGuiItemFlags_NoNav | ImGuiItemFlags_NoNavDefaultFocus;
-    bool item_add = ItemAdd(bb, id);
-    window->DC.ItemFlags = item_flags_backup;
-    if (!item_add)
-        return false;
-
-    bool hovered, held;
-    ImRect bb_interact = bb;
-    bb_interact.Expand(axis == ImGuiAxis_Y ? ImVec2(0.0f, hover_extend) : ImVec2(hover_extend, 0.0f));
-    ButtonBehavior(bb_interact, id, &hovered, &held, ImGuiButtonFlags_FlattenChildren | ImGuiButtonFlags_AllowItemOverlap);
-    if (g.ActiveId != id)
-        SetItemAllowOverlap();
-
-    if (held || (g.HoveredId == id && g.HoveredIdPreviousFrame == id && g.HoveredIdTimer >= hover_visibility_delay))
-        SetMouseCursor(axis == ImGuiAxis_Y ? ImGuiMouseCursor_ResizeNS : ImGuiMouseCursor_ResizeEW);
-
-    ImRect bb_render = bb;
-    if (held)
-    {
-        ImVec2 mouse_delta_2d = g.IO.MousePos - g.ActiveIdClickOffset - bb_interact.Min;
-        float mouse_delta = (axis == ImGuiAxis_Y) ? mouse_delta_2d.y : mouse_delta_2d.x;
-
-        // Minimum pane size
-        float size_1_maximum_delta = ImMax(0.0f, *size1 - min_size1);
-        float size_2_maximum_delta = ImMax(0.0f, *size2 - min_size2);
-        if (mouse_delta < -size_1_maximum_delta)
-            mouse_delta = -size_1_maximum_delta;
-        if (mouse_delta > size_2_maximum_delta)
-            mouse_delta = size_2_maximum_delta;
-
-        // Apply resize
-        if (mouse_delta != 0.0f)
-        {
-            if (mouse_delta < 0.0f)
-                IM_ASSERT(*size1 + mouse_delta >= min_size1);
-            if (mouse_delta > 0.0f)
-               IM_ASSERT(*size2 - mouse_delta >= min_size2);
-            *size1 += mouse_delta;
-            *size2 -= mouse_delta;
-            bb_render.Translate((axis == ImGuiAxis_X) ? ImVec2(mouse_delta, 0.0f) : ImVec2(0.0f, mouse_delta));
-            MarkItemEdited(id);
-        }
-    }
-
-    // Render
-    const ImU32 col = GetColorU32(held ? ImGuiCol_SeparatorActive : (hovered && g.HoveredIdTimer >= hover_visibility_delay) ? ImGuiCol_SeparatorHovered : ImGuiCol_Separator);
-    window->DrawList->AddRectFilled(bb_render.Min, bb_render.Max, col, g.Style.FrameRounding);
-
-    return held;
-}
-
-void ImGui::Spacing()
-{
-    ImGuiWindow* window = GetCurrentWindow();
-    if (window->SkipItems)
-        return;
-    ItemSize(ImVec2(0,0));
-}
-
-void ImGui::Dummy(const ImVec2& size)
-{
-    ImGuiWindow* window = GetCurrentWindow();
-    if (window->SkipItems)
-        return;
-
-    const ImRect bb(window->DC.CursorPos, window->DC.CursorPos + size);
-    ItemSize(bb);
-    ItemAdd(bb, 0);
-}
-
 bool ImGui::IsRectVisible(const ImVec2& size)
 {
     ImGuiWindow* window = GetCurrentWindowRead();
@@ -6689,22 +6542,6 @@ void ImGui::SameLine(float pos_x, float spacing_w)
     window->DC.CurrentLineTextBaseOffset = window->DC.PrevLineTextBaseOffset;
 }
 
-void ImGui::NewLine()
-{
-    ImGuiWindow* window = GetCurrentWindow();
-    if (window->SkipItems)
-        return;
-
-    ImGuiContext& g = *GImGui;
-    const ImGuiLayoutType backup_layout_type = window->DC.LayoutType;
-    window->DC.LayoutType = ImGuiLayoutType_Vertical;
-    if (window->DC.CurrentLineSize.y > 0.0f)     // In the event that we are on a line with items that is smaller that FontSize high, we will preserve its height.
-        ItemSize(ImVec2(0,0));
-    else
-        ItemSize(ImVec2(0.0f, g.FontSize));
-    window->DC.LayoutType = backup_layout_type;
-}
-
 void ImGui::Indent(float indent_w)
 {
     ImGuiContext& g = *GImGui;

imgui_widgets.cpp

@@ -6,6 +6,7 @@
 Index of this file:
 - Widgets: Text, etc.
 - Widgets: Button, Image, Checkbox, RadioButton, ProgressBar, Bullet, etc.
+- Widgets: Low-level Layout helpers: Spacing, Dummy, NewLine, Separator, etc.
 - Widgets: ComboBox
 - Data Type and Data Formatting Helpers
 - Widgets: DragScalar, DragFloat, DragInt, etc.
@@ -1051,6 +1052,187 @@ void ImGui::Bullet()
     SameLine(0, style.FramePadding.x*2);
 }
 
+//-------------------------------------------------------------------------
+// WIDGETS: Low-level Layout helpers
+// - Spacing()
+// - Dummy()
+// - NewLine()
+// - AlignTextToFramePadding()
+// - Separator()
+// - VerticalSeparator() [Internal]
+// - SplitterBehavior() [Internal]
+//-------------------------------------------------------------------------
+
+void ImGui::Spacing()
+{
+    ImGuiWindow* window = GetCurrentWindow();
+    if (window->SkipItems)
+        return;
+    ItemSize(ImVec2(0,0));
+}
+
+void ImGui::Dummy(const ImVec2& size)
+{
+    ImGuiWindow* window = GetCurrentWindow();
+    if (window->SkipItems)
+        return;
+
+    const ImRect bb(window->DC.CursorPos, window->DC.CursorPos + size);
+    ItemSize(bb);
+    ItemAdd(bb, 0);
+}
+
+void ImGui::NewLine()
+{
+    ImGuiWindow* window = GetCurrentWindow();
+    if (window->SkipItems)
+        return;
+
+    ImGuiContext& g = *GImGui;
+    const ImGuiLayoutType backup_layout_type = window->DC.LayoutType;
+    window->DC.LayoutType = ImGuiLayoutType_Vertical;
+    if (window->DC.CurrentLineSize.y > 0.0f)     // In the event that we are on a line with items that is smaller that FontSize high, we will preserve its height.
+        ItemSize(ImVec2(0,0));
+    else
+        ItemSize(ImVec2(0.0f, g.FontSize));
+    window->DC.LayoutType = backup_layout_type;
+}
+
+void ImGui::AlignTextToFramePadding()
+{
+    ImGuiWindow* window = GetCurrentWindow();
+    if (window->SkipItems)
+        return;
+
+    ImGuiContext& g = *GImGui;
+    window->DC.CurrentLineSize.y = ImMax(window->DC.CurrentLineSize.y, g.FontSize + g.Style.FramePadding.y * 2);
+    window->DC.CurrentLineTextBaseOffset = ImMax(window->DC.CurrentLineTextBaseOffset, g.Style.FramePadding.y);
+}
+
+// Horizontal/vertical separating line
+void ImGui::Separator()
+{
+    ImGuiWindow* window = GetCurrentWindow();
+    if (window->SkipItems)
+        return;
+    ImGuiContext& g = *GImGui;
+
+    // Those flags should eventually be overridable by the user
+    ImGuiSeparatorFlags flags = (window->DC.LayoutType == ImGuiLayoutType_Horizontal) ? ImGuiSeparatorFlags_Vertical : ImGuiSeparatorFlags_Horizontal;
+    IM_ASSERT(ImIsPowerOfTwo((int)(flags & (ImGuiSeparatorFlags_Horizontal | ImGuiSeparatorFlags_Vertical))));   // Check that only 1 option is selected
+    if (flags & ImGuiSeparatorFlags_Vertical)
+    {
+        VerticalSeparator();
+        return;
+    }
+
+    // Horizontal Separator
+    if (window->DC.ColumnsSet)
+        PopClipRect();
+
+    float x1 = window->Pos.x;
+    float x2 = window->Pos.x + window->Size.x;
+    if (!window->DC.GroupStack.empty())
+        x1 += window->DC.Indent.x;
+
+    const ImRect bb(ImVec2(x1, window->DC.CursorPos.y), ImVec2(x2, window->DC.CursorPos.y+1.0f));
+    ItemSize(ImVec2(0.0f, 0.0f)); // NB: we don't provide our width so that it doesn't get feed back into AutoFit, we don't provide height to not alter layout.
+    if (!ItemAdd(bb, 0))
+    {
+        if (window->DC.ColumnsSet)
+            PushColumnClipRect();
+        return;
+    }
+
+    window->DrawList->AddLine(bb.Min, ImVec2(bb.Max.x,bb.Min.y), GetColorU32(ImGuiCol_Separator));
+
+    if (g.LogEnabled)
+        LogRenderedText(NULL, IM_NEWLINE "--------------------------------");
+
+    if (window->DC.ColumnsSet)
+    {
+        PushColumnClipRect();
+        window->DC.ColumnsSet->LineMinY = window->DC.CursorPos.y;
+    }
+}
+
+void ImGui::VerticalSeparator()
+{
+    ImGuiWindow* window = GetCurrentWindow();
+    if (window->SkipItems)
+        return;
+    ImGuiContext& g = *GImGui;
+
+    float y1 = window->DC.CursorPos.y;
+    float y2 = window->DC.CursorPos.y + window->DC.CurrentLineSize.y;
+    const ImRect bb(ImVec2(window->DC.CursorPos.x, y1), ImVec2(window->DC.CursorPos.x + 1.0f, y2));
+    ItemSize(ImVec2(bb.GetWidth(), 0.0f));
+    if (!ItemAdd(bb, 0))
+        return;
+
+    window->DrawList->AddLine(ImVec2(bb.Min.x, bb.Min.y), ImVec2(bb.Min.x, bb.Max.y), GetColorU32(ImGuiCol_Separator));
+    if (g.LogEnabled)
+        LogText(" |");
+}
+
+// Using 'hover_visibility_delay' allows us to hide the highlight and mouse cursor for a short time, which can be convenient to reduce visual noise.
+bool ImGui::SplitterBehavior(const ImRect& bb, ImGuiID id, ImGuiAxis axis, float* size1, float* size2, float min_size1, float min_size2, float hover_extend, float hover_visibility_delay)
+{
+    ImGuiContext& g = *GImGui;
+    ImGuiWindow* window = g.CurrentWindow;
+
+    const ImGuiItemFlags item_flags_backup = window->DC.ItemFlags;
+    window->DC.ItemFlags |= ImGuiItemFlags_NoNav | ImGuiItemFlags_NoNavDefaultFocus;
+    bool item_add = ItemAdd(bb, id);
+    window->DC.ItemFlags = item_flags_backup;
+    if (!item_add)
+        return false;
+
+    bool hovered, held;
+    ImRect bb_interact = bb;
+    bb_interact.Expand(axis == ImGuiAxis_Y ? ImVec2(0.0f, hover_extend) : ImVec2(hover_extend, 0.0f));
+    ButtonBehavior(bb_interact, id, &hovered, &held, ImGuiButtonFlags_FlattenChildren | ImGuiButtonFlags_AllowItemOverlap);
+    if (g.ActiveId != id)
+        SetItemAllowOverlap();
+
+    if (held || (g.HoveredId == id && g.HoveredIdPreviousFrame == id && g.HoveredIdTimer >= hover_visibility_delay))
+        SetMouseCursor(axis == ImGuiAxis_Y ? ImGuiMouseCursor_ResizeNS : ImGuiMouseCursor_ResizeEW);
+
+    ImRect bb_render = bb;
+    if (held)
+    {
+        ImVec2 mouse_delta_2d = g.IO.MousePos - g.ActiveIdClickOffset - bb_interact.Min;
+        float mouse_delta = (axis == ImGuiAxis_Y) ? mouse_delta_2d.y : mouse_delta_2d.x;
+
+        // Minimum pane size
+        float size_1_maximum_delta = ImMax(0.0f, *size1 - min_size1);
+        float size_2_maximum_delta = ImMax(0.0f, *size2 - min_size2);
+        if (mouse_delta < -size_1_maximum_delta)
+            mouse_delta = -size_1_maximum_delta;
+        if (mouse_delta > size_2_maximum_delta)
+            mouse_delta = size_2_maximum_delta;
+
+        // Apply resize
+        if (mouse_delta != 0.0f)
+        {
+            if (mouse_delta < 0.0f)
+                IM_ASSERT(*size1 + mouse_delta >= min_size1);
+            if (mouse_delta > 0.0f)
+                IM_ASSERT(*size2 - mouse_delta >= min_size2);
+            *size1 += mouse_delta;
+            *size2 -= mouse_delta;
+            bb_render.Translate((axis == ImGuiAxis_X) ? ImVec2(mouse_delta, 0.0f) : ImVec2(0.0f, mouse_delta));
+            MarkItemEdited(id);
+        }
+    }
+
+    // Render
+    const ImU32 col = GetColorU32(held ? ImGuiCol_SeparatorActive : (hovered && g.HoveredIdTimer >= hover_visibility_delay) ? ImGuiCol_SeparatorHovered : ImGuiCol_Separator);
+    window->DrawList->AddRectFilled(bb_render.Min, bb_render.Max, col, g.Style.FrameRounding);
+
+    return held;
+}
+
 //-------------------------------------------------------------------------
 // WIDGETS: Combo Box
 // - BeginCombo()