Log/Capture: Fixed BeginTabItem() label not being included in a text log/capture.

Extracted tab rendering code into a RenderTextEllipsis() function.

docs/CHANGELOG.txt

@@ -83,6 +83,7 @@ Other Changes:
 - Style: Added style.WindowMenuButtonPosition (left/right, defaults to ImGuiDir_Left) to move the
   collapsing/docking button to the other side of the title bar.
 - Style: Made window close button cross slightly smaller.
+- Log/Capture: Fixed BeginTabItem() label not being included in a text log/capture.
 - ImDrawList: Added ImDrawCmd::VtxOffset value to support large meshes (64k+ vertices) using 16-bits indices.
   The renderer back-end needs to set 'io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset' to enable
   this, and honor the ImDrawCmd::VtxOffset field. Otherwise the value will always be zero.

imgui.cpp

@@ -2422,6 +2422,51 @@ void ImGui::RenderTextClipped(const ImVec2& pos_min, const ImVec2& pos_max, cons
         LogRenderedText(&pos_min, text, text_display_end);
 }
 
+
+// Another overly complex function until we reorganize everything into a nice all-in-one helper.
+// This is made more complex because we have dissociated the layout rectangle (pos_min..pos_max) which define where the ellipsis is, from actual clipping and limit of the ellipsis display.
+// This is because in the context of tabs we selectively hide part of the text when the Close Button appears, but we don't want the ellipsis to move. 
+void    ImGui::RenderTextEllipsis(ImDrawList* draw_list, const ImVec2& pos_min, const ImVec2& pos_max, float clip_max_x, float ellipsis_max_x, const char* text, const char* text_end_full, const ImVec2* text_size_if_known)
+{
+    ImGuiContext& g = *GImGui;
+    if (text_end_full == NULL)
+        text_end_full = FindRenderedTextEnd(text);
+    const ImVec2 text_size = text_size_if_known ? *text_size_if_known : CalcTextSize(text, text_end_full, false, 0.0f);
+
+    if (text_size.x > pos_max.x - pos_min.x)
+    {
+
+        const ImFont* font = draw_list->_Data->Font;
+        const float font_size = draw_list->_Data->FontSize;
+        const int ellipsis_dot_count = 3;
+        const float ellipsis_width = (1.0f + 1.0f) * ellipsis_dot_count - 1.0f;
+        const char* text_end_ellipsis = NULL;
+        float text_size_clipped_x = font->CalcTextSizeA(font_size, (pos_max.x - pos_min.x) - ellipsis_width + 1.0f, 0.0f, text, text_end_full, &text_end_ellipsis).x;
+        if (text == text_end_ellipsis && text_end_ellipsis < text_end_full)    // Always display at least 1 character if there's no room for character + ellipsis
+        {
+            text_end_ellipsis = text + ImTextCountUtf8BytesFromChar(text, text_end_full);
+            text_size_clipped_x = font->CalcTextSizeA(font_size, FLT_MAX, 0.0f, text, text_end_ellipsis).x;
+        }
+        while (text_end_ellipsis > text && ImCharIsBlankA(text_end_ellipsis[-1])) // Trim trailing space
+        {
+            text_end_ellipsis--;
+            text_size_clipped_x -= font->CalcTextSizeA(font_size, FLT_MAX, 0.0f, text_end_ellipsis, text_end_ellipsis + 1).x; // Ascii blanks are always 1 byte
+        }
+        RenderTextClippedEx(draw_list, pos_min, ImVec2(clip_max_x, pos_max.y), text, text_end_ellipsis, &text_size, ImVec2(0.0f, 0.0f));
+
+        const float ellipsis_x = pos_min.x + text_size_clipped_x + 1.0f;
+        if (ellipsis_x + ellipsis_width <= ellipsis_max_x)
+            RenderPixelEllipsis(draw_list, ImVec2(ellipsis_x, pos_min.y), GetColorU32(ImGuiCol_Text), ellipsis_dot_count);
+    }
+    else
+    {
+        RenderTextClippedEx(draw_list, pos_min, ImVec2(clip_max_x, pos_max.y), text, text_end_full, &text_size, ImVec2(0.0f, 0.0f));
+    }
+
+    if (g.LogEnabled)
+        LogRenderedText(&pos_min, text, text_end_full);
+}
+
 // 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)
 {

imgui_internal.h

@@ -1575,6 +1575,7 @@ namespace ImGui
     IMGUI_API void          RenderTextWrapped(ImVec2 pos, const char* text, const char* text_end, float wrap_width);
     IMGUI_API void          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 = ImVec2(0,0), const ImRect* clip_rect = NULL);
     IMGUI_API void          RenderTextClippedEx(ImDrawList* draw_list, const ImVec2& pos_min, const ImVec2& pos_max, const char* text, const char* text_end, const ImVec2* text_size_if_known, const ImVec2& align = ImVec2(0, 0), const ImRect* clip_rect = NULL);
+    IMGUI_API void          RenderTextEllipsis(ImDrawList* draw_list, const ImVec2& pos_min, const ImVec2& pos_max, float clip_max_x, float ellipsis_max_x, const char* text, const char* text_end, const ImVec2* text_size_if_known);
     IMGUI_API void          RenderFrame(ImVec2 p_min, ImVec2 p_max, ImU32 fill_col, bool border = true, float rounding = 0.0f);
     IMGUI_API void          RenderFrameBorder(ImVec2 p_min, ImVec2 p_max, float rounding = 0.0f);
     IMGUI_API void          RenderColorRectWithAlphaCheckerboard(ImVec2 p_min, ImVec2 p_max, ImU32 fill_col, float grid_step, ImVec2 grid_off, float rounding = 0.0f, int rounding_corners_flags = ~0);

imgui_widgets.cpp

@@ -7077,35 +7077,8 @@ bool ImGui::TabItemLabelAndCloseButton(ImDrawList* draw_list, const ImRect& bb,
         text_pixel_clip_bb.Max.x -= close_button_sz;
     }
 
-    // Label with ellipsis
-    // FIXME: This should be extracted into a helper but the use of text_pixel_clip_bb and !close_button_visible makes it tricky to abstract at the moment
-    const char* label_display_end = FindRenderedTextEnd(label);
-    if (label_size.x > text_ellipsis_clip_bb.GetWidth())
-    {
-        const int ellipsis_dot_count = 3;
-        const float ellipsis_width = (1.0f + 1.0f) * ellipsis_dot_count - 1.0f;
-        const char* label_end = NULL;
-        float label_size_clipped_x = g.Font->CalcTextSizeA(g.FontSize, text_ellipsis_clip_bb.GetWidth() - ellipsis_width + 1.0f, 0.0f, label, label_display_end, &label_end).x;
-        if (label_end == label && label_end < label_display_end)    // Always display at least 1 character if there's no room for character + ellipsis
-        {
-            label_end = label + ImTextCountUtf8BytesFromChar(label, label_display_end);
-            label_size_clipped_x = g.Font->CalcTextSizeA(g.FontSize, FLT_MAX, 0.0f, label, label_end).x;
-        }
-        while (label_end > label && ImCharIsBlankA(label_end[-1])) // Trim trailing space
-        {
-            label_end--;
-            label_size_clipped_x -= g.Font->CalcTextSizeA(g.FontSize, FLT_MAX, 0.0f, label_end, label_end + 1).x; // Ascii blanks are always 1 byte
-        }
-        RenderTextClippedEx(draw_list, text_pixel_clip_bb.Min, text_pixel_clip_bb.Max, label, label_end, &label_size, ImVec2(0.0f, 0.0f));
-
-        const float ellipsis_x = text_pixel_clip_bb.Min.x + label_size_clipped_x + 1.0f;
-        if (!close_button_visible && ellipsis_x + ellipsis_width <= bb.Max.x)
-            RenderPixelEllipsis(draw_list, ImVec2(ellipsis_x, text_pixel_clip_bb.Min.y), GetColorU32(ImGuiCol_Text), ellipsis_dot_count);
-    }
-    else
-    {
-        RenderTextClippedEx(draw_list, text_pixel_clip_bb.Min, text_pixel_clip_bb.Max, label, label_display_end, &label_size, ImVec2(0.0f, 0.0f));
-    }
+    float ellipsis_max_x = close_button_visible ? -FLT_MAX : bb.Max.x;
+    RenderTextEllipsis(draw_list, text_ellipsis_clip_bb.Min, text_ellipsis_clip_bb.Max, text_pixel_clip_bb.Max.x, ellipsis_max_x, label, NULL, &label_size);
 
     return close_button_pressed;
 }