private static int LayoutRow(LGuiTextFieldState State, LGuiFont Font, int StartIndex, ref LGuiVec2 TextSize)
{
var Index = StartIndex;
var LineWidth = 0.0f;
TextSize.X = 0;
TextSize.Y = 0;
while (Index < State.TextLength)
{
var Ch = State.GetCharacter(Index++);
if (Ch == '\n')
{
TextSize.X = LGuiMisc.Max(TextSize.X, LineWidth);
TextSize.Y = TextSize.Y + Font.FontHeight + State.Spacing.Y;
LineWidth = 0.0f;
break;
}
if (Ch == '\r')
{
continue;
}
LineWidth = LineWidth + Font.FontWidth + State.Spacing.X;
}
if (TextSize.X < LineWidth)
{
TextSize.X = LineWidth;
}
if (LineWidth > 0 || TextSize.Y == 0.0f)
{
TextSize.Y = TextSize.Y + Font.FontHeight + State.Spacing.Y;
}
return(Index - StartIndex);
}
private static int LocateCoord(LGuiTextFieldState State, LGuiFont Font, LGuiVec2 Pos)
{
var Length = State.TextLength;
var Index = 0;
var BaseY = 0.0f;
var Size = LGuiVec2.Zero;
var NumChars = 0;
while (Index < Length)
{
NumChars = LayoutRow(State, Font, Index, ref Size);
if (NumChars <= 0)
{
return(Length);
}
if (Index == 0 && Pos.Y < BaseY)
{
return(0);
}
if (Pos.Y < BaseY + Size.Y)
{
break;
}
Index += NumChars;
BaseY += Size.Y;
}
if (Index >= Length)
{
return(Length);
}
if (Pos.X < 0)
{
return(Index);
}
if (Pos.X < Size.X)
{
var PrevX = 0.0f;
for (var N = 0; N < NumChars; ++N)
{
var Width = Font.FontWidth + State.Spacing.X;
if (Pos.X < PrevX + Width)
{
if (Pos.X < PrevX + Width / 2.0f)
{
return(Index + N);
}
else
{
return(Index + N + 1);
}
}
PrevX += Width;
}
}
if (State.GetCharacter(Index + NumChars - 1) == '\n')
{
return(Index + NumChars - 1);
}
return(Index + NumChars);
}