public static bool Begin(string name, ref bool open, Point position, Size size, double bg_alpha = 1, WindowFlags flags = WindowFlags.VerticalScrollbar)
{
Form form = Form.current;
GUIContext g = form.uiContext;
WindowManager w = g.WindowManager;
Debug.Assert(name != null); // Window name required
Debug.Assert(g.Initialized); // Forgot to call NewFrame()
Debug.Assert(g.FrameCountEnded != g.FrameCount); // Called Render() or EndFrame() and haven't called NewFrame() again yet
if (flags.HaveFlag(WindowFlags.NoInputs))
{
flags |= WindowFlags.NoMove | WindowFlags.NoResize;
}
// Find or create
Window window = w.FindWindowByName(name) ?? w.CreateWindow(name, position, size, flags);
// Check if this is the first call of Begin
long current_frame = g.FrameCount;
bool first_begin_of_the_frame = (window.LastActiveFrame != current_frame);
if (first_begin_of_the_frame)
{
window.Flags = flags;
}
else
{
flags = window.Flags;
}
// Add to stack
Window parent_window = w.WindowStack.Count != 0 ? w.WindowStack[w.WindowStack.Count - 1] : null;
w.WindowStack.Add(window);
w.CurrentWindow = window;
Debug.Assert(parent_window != null || !flags.HaveFlag(WindowFlags.ChildWindow));
// Update known root window (if we are a child window, otherwise window == window->RootWindow)
int root_idx;
for (root_idx = w.WindowStack.Count - 1; root_idx > 0; root_idx--)
{
if (!(w.WindowStack[root_idx].Flags.HaveFlag(WindowFlags.ChildWindow)))
{
break;
}
}
window.RootWindow = w.WindowStack[root_idx];
// When reusing window again multiple times a frame, just append content (don't need to setup again)
if (first_begin_of_the_frame)
{
window.Active = true;
window.BeginCount = 0;
window.ClipRect = Rect.Big;
window.LastActiveFrame = current_frame;
// clear draw list, setup outer clip rect
window.DrawList.Clear();
window.DrawList.Init();
Rect fullScreenRect = new Rect(0, 0, form.ClientSize);
if (flags.HaveFlag(WindowFlags.ChildWindow) && !flags.HaveFlag(WindowFlags.ComboBox | WindowFlags.Popup))
{
window.DrawList.PushClipRect(parent_window.ClipRect, true);
window.ClipRect = window.DrawList.GetCurrentClipRect();
}
else
{
window.DrawList.PushClipRect(fullScreenRect, true);
window.ClipRect = window.DrawList.GetCurrentClipRect();
}
// draw outer clip rect
//window.DrawList.AddRect(window.ClipRect.TopLeft, window.ClipRect.BottomRight, Color.Blue);//test only
// Collapse window by double-clicking on title bar
if (!(flags.HaveFlag(WindowFlags.NoTitleBar)) && !(flags.HaveFlag(WindowFlags.NoCollapse)))
{
if (w.HoveredWindow == window && g.IsMouseHoveringRect(window.TitleBarRect) && Mouse.Instance.LeftButtonDoubleClicked)
{
window.Collapsed = !window.Collapsed;
w.FocusWindow(window);
}
}
else
{
window.Collapsed = false;
}
#region size
window.ApplySize(window.FullSize);
window.Size = window.Collapsed ? window.TitleBarRect.Size : window.FullSize;
#endregion
#region position
window.Position = new Point((int)window.PosFloat.X, (int)window.PosFloat.Y);
if (flags.HaveFlag(WindowFlags.ChildWindow))
{
window.Position = window.PosFloat = position;
window.Size = window.FullSize = size; // 'size' provided by user passed via BeginChild()->Begin().
}
#endregion
// Draw window + handle manual resize
GUIStyle style = window.Style;
GUIStyle titleBarStyle = window.TitleBarStyle;
Rect title_bar_rect = window.TitleBarRect;
float window_rounding = (float)style.Get <double>(GUIStyleName.WindowRounding);
if (window.Collapsed)
{
// Draw title bar only
window.DrawList.AddRectFilled(title_bar_rect.Min, title_bar_rect.Max, new Color(0.40f, 0.40f, 0.80f, 0.50f));
}
else
{
Color resize_col = Color.Clear;
double rezie_size = window.Style.Get <double>(GUIStyleName.ResizeGripSize);
double resize_corner_size = Math.Max(rezie_size * 1.35, window_rounding + 1.0 + rezie_size * 0.2);
if (!flags.HaveFlag(WindowFlags.AlwaysAutoResize) && !flags.HaveFlag(WindowFlags.NoResize))
{
// Manual resize
var br = window.Rect.BottomRight;
Rect resize_rect = new Rect(br - new Vector(resize_corner_size * 0.75f, resize_corner_size * 0.75f), br);
int resize_id = window.GetID("#RESIZE");
bool hovered, held;
GUIBehavior.ButtonBehavior(resize_rect, resize_id, out hovered, out held, ButtonFlags.FlattenChilds);
resize_col =
held ? style.Get <Color>(GUIStyleName.ResizeGripColor, GUIState.Active) :
hovered?style.Get <Color>(GUIStyleName.ResizeGripColor, GUIState.Hover) :
style.Get <Color>(GUIStyleName.ResizeGripColor);
if (hovered || held)
{
//Mouse.Instance.Cursor = Cursor.NeswResize;
}
if (held)
{
// We don't use an incremental MouseDelta but rather compute an absolute target size based on mouse position
var t = Mouse.Instance.Position - g.ActiveIdClickOffset - window.Position;
var new_size_width = t.X + resize_rect.Width;
var new_size_height = t.Y + resize_rect.Height;
new_size_width = MathEx.Clamp(new_size_width, 330, fullScreenRect.Width);//min size of a window is 145x235
new_size_height = MathEx.Clamp(new_size_height, 150, fullScreenRect.Height);
Size resize_size = new Size(new_size_width, new_size_height);
window.ApplySize(resize_size);
// adjust scroll parameters
var contentSize = window.ContentRect.Size;
if (contentSize != Size.Zero)
{
var vH = window.Rect.Height - window.TitleBarHeight - window.Style.BorderVertical - window.Style.PaddingVertical;
var cH = contentSize.Height;
if (cH > vH)
{
var oldScrollY = window.Scroll.Y;
oldScrollY = MathEx.Clamp(oldScrollY, 0, cH - vH);
window.Scroll.Y = oldScrollY;
}
}
}
window.Size = window.FullSize;
title_bar_rect = window.TitleBarRect;
}
// Window background
Color bg_color = style.BackgroundColor;
if (bg_alpha >= 0.0f)
{
bg_color.A = bg_alpha;
}
if (bg_color.A > 0.0f)
{
window.DrawList.AddRectFilled(window.Position + new Vector(0, window.TitleBarHeight), window.Rect.BottomRight, bg_color, window_rounding, flags.HaveFlag(WindowFlags.NoTitleBar) ? 15 : 4 | 8);
}
// Title bar
if (!flags.HaveFlag(WindowFlags.NoTitleBar))
{
window.DrawList.AddRectFilled(title_bar_rect.TopLeft, title_bar_rect.BottomRight,
w.FocusedWindow == window ?
titleBarStyle.Get <Color>(GUIStyleName.BackgroundColor, GUIState.Active) :
titleBarStyle.Get <Color>(GUIStyleName.BackgroundColor), window_rounding, 1 | 2);
}
// Render resize grip
// (after the input handling so we don't have a frame of latency)
if (!flags.HaveFlag(WindowFlags.NoResize))
{
Point br = window.Rect.BottomRight;
var borderBottom = window.Style.BorderBottom;
var borderRight = window.Style.BorderRight;
window.DrawList.PathLineTo(br + new Vector(-resize_corner_size, -borderBottom));
window.DrawList.PathLineTo(br + new Vector(-borderRight, -resize_corner_size));
window.DrawList.PathArcToFast(new Point(br.X - window_rounding - borderRight, br.Y - window_rounding - borderBottom), window_rounding, 0, 3);
window.DrawList.PathFill(resize_col);
}
// Scroll bar
if (flags.HaveFlag(WindowFlags.VerticalScrollbar))
{
//get content size without clip
var contentPosition = window.ContentRect.TopLeft;
var contentSize = window.ContentRect.Size;
if (contentSize != Size.Zero)
{
int id = window.GetID("#SCROLLY");
double scrollBarWidth = window.Style.Get <double>(GUIStyleName.ScrollBarWidth);
Point scroll_TopLeft = new Point(
window.Rect.Right - scrollBarWidth - window.Style.BorderRight - window.Style.PaddingRight,
window.Rect.Top + window.TitleBarHeight + window.Style.BorderTop + window.Style.PaddingTop);
var sH = window.Rect.Height - window.TitleBarHeight - window.Style.BorderVertical - window.Style.PaddingVertical - resize_corner_size;
var vH = window.Rect.Height - window.TitleBarHeight - window.Style.BorderVertical - window.Style.PaddingVertical;
Point scroll_BottomRight = scroll_TopLeft + new Vector(scrollBarWidth, sH);
Rect bgRect = new Rect(scroll_TopLeft, scroll_BottomRight);
var cH = contentSize.Height;
var top = window.Scroll.Y * sH / cH;
var height = sH * vH / cH;
if (height < sH)
{
// handle mouse click/drag
bool held = false;
bool hovered = false;
bool previously_held = (g.ActiveId == id);
GUIBehavior.ButtonBehavior(bgRect, id, out hovered, out held);
if (held)
{
top = Mouse.Instance.Position.Y - bgRect.Y - 0.5 * height;
top = MathEx.Clamp(top, 0, sH - height);
var targetScrollY = top * cH / sH;
window.SetWindowScrollY(targetScrollY);
}
Point scrollButton_TopLeft = scroll_TopLeft + new Vector(0, top);
Point scrllButton_BottomRight = scrollButton_TopLeft + new Vector(scrollBarWidth, height);
Rect buttonRect = new Rect(scrollButton_TopLeft, scrllButton_BottomRight);
//Draw vertical scroll bar and button
{
var bgColor = window.Style.Get <Color>(GUIStyleName.ScrollBarBackgroundColor);
var buttonColor = window.Style.Get <Color>(GUIStyleName.ScrollBarButtonColor, held ? GUIState.Active : hovered ? GUIState.Hover : GUIState.Normal);
window.DrawList.AddRectFilled(bgRect.TopLeft, buttonRect.TopRight, bgColor);
window.DrawList.AddRectFilled(buttonRect.TopLeft, buttonRect.BottomRight, buttonColor);
window.DrawList.AddRectFilled(buttonRect.BottomLeft, bgRect.BottomRight, bgColor);
}
}
else
{
var bgColor = window.Style.Get <Color>(GUIStyleName.ScrollBarBackgroundColor);
window.DrawList.AddRectFilled(bgRect.TopLeft, bgRect.BottomRight, bgColor);
}
}
}
window.ContentRect = Rect.Zero;
}
// draw title bar text
if (!flags.HaveFlag(WindowFlags.NoTitleBar))
{
var state = w.FocusedWindow == window ? GUIState.Active : GUIState.Normal;
window.DrawList.DrawBoxModel(title_bar_rect, name, titleBarStyle, state);
}
// Borders
if (flags.HaveFlag(WindowFlags.ShowBorders))
{
var state = w.FocusedWindow == window ? GUIState.Active : GUIState.Normal;
// window border
var borderColor = window.Style.Get <Color>(GUIStyleName.WindowBorderColor, state);
window.DrawList.AddRect(window.Position, window.Position + new Vector(window.Size.Width, window.Size.Height),
borderColor, window_rounding);
// window shadow
#if false
{
var state = w.FocusedWindow == window ? GUIState.Active : GUIState.Normal;
var shadowColor = window.Style.Get <Color>(GUIStyleName.WindowShadowColor, state);
var shadowWidth = window.Style.Get <double>(GUIStyleName.WindowShadowWidth, state);
var d = window.DrawList;
//top-left corner
d.AddRectFilledGradientTopLeftToBottomRight(window.Rect.TopLeft + new Vector(-shadowWidth, -shadowWidth), window.Rect.TopLeft, Color.Clear, shadowColor);
//top
d.AddRectFilledGradient(window.Rect.TopLeft + new Vector(0, -shadowWidth), window.Rect.TopRight, Color.Clear, shadowColor);
d.AddRectFilledGradient(window.Rect.BottomLeft, window.Rect.BottomRight + new Vector(0, shadowWidth), shadowColor, Color.Clear);
}
#endif
}
// Save clipped aabb so we can access it in constant-time in FindHoveredWindow()
window.WindowClippedRect = window.Rect;
window.WindowClippedRect.Intersect(window.ClipRect);
}
// Inner clipping rectangle
{
// We set this up after processing the resize grip so that our clip rectangle doesn't lag by a frame
// Note that if our window is collapsed we will end up with a null clipping rectangle which is the correct behavior.
Rect title_bar_rect = window.TitleBarRect;
const float border_size = 0;
var paddingHorizontal = window.Style.PaddingHorizontal;
// Force round to ensure that e.g. (int)(max.x-min.x) in user's render code produce correct result.
Rect clip_rect = new Rect(
new Point(Math.Floor(0.5f + title_bar_rect.Min.X + Math.Max(border_size, Math.Floor(paddingHorizontal * 0.5f))),
Math.Floor(0.5f + title_bar_rect.Max.Y + border_size)),
new Point(Math.Floor(0.5f + window.Position.X + window.Size.Width - Math.Max(border_size, Math.Floor(paddingHorizontal * 0.5f))),
Math.Floor(0.5f + window.Position.Y + window.Size.Height - border_size)));
window.DrawList.PushClipRect(clip_rect, true);
window.ClipRect = clip_rect;
//window.DrawList.AddRect(window.ClipRect.TopLeft, window.ClipRect.BottomRight, Color.Red);//test only
}
// Clear 'accessed' flag last thing
if (first_begin_of_the_frame)
{
window.Accessed = false;
}
window.BeginCount++;
// Child window can be out of sight and have "negative" clip windows.
// Mark them as collapsed so commands are skipped earlier (we can't manually collapse because they have no title bar).
if (flags.HaveFlag(WindowFlags.ChildWindow))
{
Debug.Assert(flags.HaveFlag(WindowFlags.NoTitleBar));
window.Collapsed = parent_window != null && parent_window.Collapsed;
}
window.StackLayout.Begin();
// Return false if we don't intend to display anything to allow user to perform an early out optimization
window.SkipItems = window.Collapsed || !window.Active;
return(!window.SkipItems);
}