Button centering left to RenderTextClipped function.

imgui.cpp

@@ -2643,6 +2643,7 @@ static void RenderTextClipped(ImVec2 pos, const char* text, const char* text_end
     // Align
     if (align & ImGuiAlign_Center) pos.x = ImMax(pos.x, (pos.x + pos_max.x - text_size.x) * 0.5f);
     else if (align & ImGuiAlign_Right) pos.x = ImMax(pos.x, pos_max.x - text_size.x);
+    if (align & ImGuiAlign_VCenter) pos.y = ImMax(pos.y, (pos.y + pos_max.y - text_size.y) * 0.5f);
 
     // Render
     window->DrawList->AddText(g.Font, g.FontSize, pos, window->Color(ImGuiCol_Text), text, text_display_end, 0.0f, need_clipping ? clip_max : NULL);
@@ -4888,9 +4889,7 @@ static bool ButtonEx(const char* label, const ImVec2& size_arg, ImGuiButtonFlags
     // Render
     const ImU32 col = window->Color((hovered && held) ? ImGuiCol_ButtonActive : hovered ? ImGuiCol_ButtonHovered : ImGuiCol_Button);
     RenderFrame(bb.Min, bb.Max, col, true, style.FrameRounding);
-
-    const ImVec2 off = ImVec2(ImMax(0.0f, size.x - label_size.x) * 0.5f, ImMax(0.0f, size.y - label_size.y) * 0.5f); // Center (only applies if we explicitly gave a size bigger than the text size, which isn't the common path)
-    RenderTextClipped(bb.Min + off, label, NULL, &label_size, bb.Max);                          // Render clip (only applies if we explicitly gave a size smaller than the text size, which isn't common)
+    RenderTextClipped(bb.Min, label, NULL, &label_size, bb.Max, NULL, ImGuiAlign_Center | ImGuiAlign_VCenter);
 
     // Automatically close popups
     if (pressed && !(flags & ImGuiButtonFlags_DontClosePopups) && (window->Flags & ImGuiWindowFlags_Popup))

imgui.h

@@ -522,7 +522,9 @@ enum ImGuiAlign_
     ImGuiAlign_Left     = 1 << 0,
     ImGuiAlign_Center   = 1 << 1,
     ImGuiAlign_Right    = 1 << 2,
-    ImGuiAlign_Default  = ImGuiAlign_Left,
+    ImGuiAlign_Top      = 1 << 3,
+    ImGuiAlign_VCenter  = 1 << 4,
+    ImGuiAlign_Default  = ImGuiAlign_Left | ImGuiAlign_Top,
 };
 
 // Enumeration for ColorEditMode()