Removed DisplayVisibleMin/DisplayVisibleMax facility (as part of # 1542). Misc comments.

imgui.cpp

@@ -250,6 +250,7 @@
  Here is a change-log of API breaking changes, if you are using one of the functions listed, expect to have to fix some code.
  Also read releases logs https://github.com/ocornut/imgui/releases for more details.
 
+ - 2018/02/27 (1.XX) - removed io.DisplayVisibleMin, io.DisplayVisibleMax settings (it was used to clip within the DisplayPos..DisplayPos+Size range, I don't know of anyone using it)
  - 2018/02/18 (1.60) - BeginDragDropSource(): temporarily removed the optional mouse_button=0 parameter because it is not really usable in many situations at the moment. 
  - 2018/02/16 (1.60) - obsoleted the io.RenderDrawListsFn callback, you can call your graphics engine render function after ImGui::Render(). Use ImGui::GetDrawData() to retrieve the ImDrawData* to display.
  - 2018/02/07 (1.60) - reorganized context handling to be more explicit,
@@ -864,7 +865,6 @@ ImGuiIO::ImGuiIO()
     FontDefault = NULL;
     FontAllowUserScaling = false;
     DisplayFramebufferScale = ImVec2(1.0f, 1.0f);
-    DisplayVisibleMin = DisplayVisibleMax = ImVec2(0.0f, 0.0f);
 
     // Advanced/subtle behaviors
 #ifdef __APPLE__
@@ -4747,8 +4747,6 @@ ImVec2 ImGui::GetItemRectSize()
 static ImRect GetViewportRect()
 {
     ImGuiContext& g = *GImGui;
-    if (g.IO.DisplayVisibleMin.x != g.IO.DisplayVisibleMax.x && g.IO.DisplayVisibleMin.y != g.IO.DisplayVisibleMax.y)
-        return ImRect(g.IO.DisplayVisibleMin, g.IO.DisplayVisibleMax);
     return ImRect(0.0f, 0.0f, g.IO.DisplaySize.x, g.IO.DisplaySize.y);
 }
 

imgui.h

@@ -970,8 +970,6 @@ struct ImGuiIO
     bool          FontAllowUserScaling;     // = false              // Allow user scaling text of individual window with CTRL+Wheel.
     ImFont*       FontDefault;              // = NULL               // Font to use on NewFrame(). Use NULL to uses Fonts->Fonts[0].
     ImVec2        DisplayFramebufferScale;  // = (1.0f,1.0f)        // For retina display or other situations where window coordinates are different from framebuffer coordinates. User storage only, presently not used by ImGui.
-    ImVec2        DisplayVisibleMin;        // <unset> (0.0f,0.0f)  // If you use DisplaySize as a virtual space larger than your screen, set DisplayVisibleMin/Max to the visible area.
-    ImVec2        DisplayVisibleMax;        // <unset> (0.0f,0.0f)  // If the values are the same, we defaults to Min=(0.0f) and Max=DisplaySize
 
     // Advanced/subtle behaviors
     bool          OptMacOSXBehaviors;       // = defined(__APPLE__) // OS X style: Text editing cursor movement using Alt instead of Ctrl, Shortcuts using Cmd/Super instead of Ctrl, Line/Text Start and End using Cmd+Arrows instead of Home/End, Double click selects by word instead of selecting whole text, Multi-selection in lists uses Cmd/Super instead of Ctrl
@@ -1004,8 +1002,8 @@ struct ImGuiIO
 
     ImVec2      MousePos;                       // Mouse position, in pixels. Set to ImVec2(-FLT_MAX,-FLT_MAX) if mouse is unavailable (on another screen, etc.)
     bool        MouseDown[5];                   // Mouse buttons: left, right, middle + extras. ImGui itself mostly only uses left button (BeginPopupContext** are using right button). Others buttons allows us to track if the mouse is being used by your application + available to user as a convenience via IsMouse** API.
-    float       MouseWheel;                     // Mouse wheel: 1 unit scrolls about 5 lines text. 
-    float       MouseWheelH;                    // Mouse wheel (Horizontal). Most users don't have a mouse with an horizontal wheel, may not be filled by all back-ends.
+    float       MouseWheel;                     // Mouse wheel Vertical: 1 unit scrolls about 5 lines text. 
+    float       MouseWheelH;                    // Mouse wheel Horizontal. Most users don't have a mouse with an horizontal wheel, may not be filled by all back-ends.
     bool        MouseDrawCursor;                // Request ImGui to draw a mouse cursor for you (if you are on a platform without a mouse cursor).
     bool        KeyCtrl;                        // Keyboard modifier pressed: Control
     bool        KeyShift;                       // Keyboard modifier pressed: Shift
@@ -1477,7 +1475,7 @@ enum ImDrawListFlags_
 // This is the low-level list of polygons that ImGui functions are filling. At the end of the frame, all command lists are passed to your ImGuiIO::RenderDrawListFn function for rendering.
 // Each ImGui window contains its own ImDrawList. You can use ImGui::GetWindowDrawList() to access the current window draw list and draw custom primitives.
 // You can interleave normal ImGui:: calls and adding primitives to the current draw list.
-// All positions are generally in pixel coordinates (top-left at (0,0), bottom-right at io.DisplaySize), however you are totally free to apply whatever transformation matrix to want to the data (if you apply such transformation you'll want to apply it to ClipRect as well)
+// All positions are generally in pixel coordinates (generally top-left at 0,0, bottom-right at io.DisplaySize, unless multiple viewports are used), however you are totally free to apply whatever transformation matrix to want to the data (if you apply such transformation you'll want to apply it to ClipRect as well)
 // Important: Primitives are always added to the list and not culled (culling is done at higher-level by ImGui:: functions), if you use this API a lot consider coarse culling your drawn objects.
 struct ImDrawList
 {