Added ImGuiWindowFlags_ForceVerticalScrollbar, ImGuiWindowFlags_ForceHorizontalScrollbar flags (#476)

imgui.cpp

@@ -3936,8 +3936,8 @@ bool ImGui::Begin(const char* name, bool* p_opened, const ImVec2& size_on_first_
             }
 
             // Scrollbars
-            window->ScrollbarY = (window->SizeContents.y > window->Size.y + style.ItemSpacing.y) && !(flags & ImGuiWindowFlags_NoScrollbar);
-            window->ScrollbarX = (window->SizeContents.x > window->Size.x - (window->ScrollbarY ? style.ScrollbarSize : 0.0f) - window->WindowPadding.x) && !(flags & ImGuiWindowFlags_NoScrollbar) && (flags & ImGuiWindowFlags_HorizontalScrollbar);
+            window->ScrollbarY = (flags & ImGuiWindowFlags_ForceVerticalScrollbar) || ((window->SizeContents.y > window->Size.y + style.ItemSpacing.y) && !(flags & ImGuiWindowFlags_NoScrollbar));
+            window->ScrollbarX = (flags & ImGuiWindowFlags_ForceHorizontalScrollbar) || ((window->SizeContents.x > window->Size.x - (window->ScrollbarY ? style.ScrollbarSize : 0.0f) - window->WindowPadding.x) && !(flags & ImGuiWindowFlags_NoScrollbar) && (flags & ImGuiWindowFlags_HorizontalScrollbar));
             window->ScrollbarSizes = ImVec2(window->ScrollbarY ? style.ScrollbarSize : 0.0f, window->ScrollbarX ? style.ScrollbarSize : 0.0f);
 
             // Window background

imgui.h

@@ -453,17 +453,19 @@ enum ImGuiWindowFlags_
     ImGuiWindowFlags_NoTitleBar             = 1 << 0,   // Disable title-bar
     ImGuiWindowFlags_NoResize               = 1 << 1,   // Disable user resizing with the lower-right grip
     ImGuiWindowFlags_NoMove                 = 1 << 2,   // Disable user moving the window
-    ImGuiWindowFlags_NoScrollbar            = 1 << 3,   // Disable scrollbar (window can still scroll with mouse or programatically)
-    ImGuiWindowFlags_NoScrollWithMouse      = 1 << 4,   // Disable user scrolling with mouse wheel
+    ImGuiWindowFlags_NoScrollbar            = 1 << 3,   // Disable scrollbars (window can still scroll with mouse or programatically)
+    ImGuiWindowFlags_NoScrollWithMouse      = 1 << 4,   // Disable user vertically scrolling with mouse wheel
     ImGuiWindowFlags_NoCollapse             = 1 << 5,   // Disable user collapsing window by double-clicking on it
     ImGuiWindowFlags_AlwaysAutoResize       = 1 << 6,   // Resize every window to its content every frame
     ImGuiWindowFlags_ShowBorders            = 1 << 7,   // Show borders around windows and items
     ImGuiWindowFlags_NoSavedSettings        = 1 << 8,   // Never load/save settings in .ini file
     ImGuiWindowFlags_NoInputs               = 1 << 9,   // Disable catching mouse or keyboard inputs
     ImGuiWindowFlags_MenuBar                = 1 << 10,  // Has a menu-bar
-    ImGuiWindowFlags_HorizontalScrollbar    = 1 << 11,  // Enable horizontal scrollbar (off by default). You need to use SetNextWindowContentSize(ImVec2(width,0.0f)); prior to calling Begin() to specify width. Read code in imgui_demo in the "Horizontal Scrolling" section.
+    ImGuiWindowFlags_HorizontalScrollbar    = 1 << 11,  // Allow horizontal scrollbar to appear (off by default). You need to use SetNextWindowContentSize(ImVec2(width,0.0f)); prior to calling Begin() to specify width. Read code in imgui_demo in the "Horizontal Scrolling" section.
     ImGuiWindowFlags_NoFocusOnAppearing     = 1 << 12,  // Disable taking focus when transitioning from hidden to visible state
     ImGuiWindowFlags_NoBringToFrontOnFocus  = 1 << 13,  // Disable bringing window to front when taking focus (e.g. clicking on it or programatically giving it focus)
+    ImGuiWindowFlags_ForceVerticalScrollbar = 1 << 14,  // Always show vertical scrollbar (even if ContentSize.y < Size.y)
+    ImGuiWindowFlags_ForceHorizontalScrollbar=1 << 15,  // Always show horizontal scrollbar (even if ContentSize.x < Size.x)
     // [Internal]
     ImGuiWindowFlags_ChildWindow            = 1 << 20,  // Don't use! For internal use by BeginChild()
     ImGuiWindowFlags_ChildWindowAutoFitX    = 1 << 21,  // Don't use! For internal use by BeginChild()