traverse the layout to locate the nearest character to a display position

discard the oldest entry in the undo list

find the x/y location of a character, and remember info about the previous row in case we get a move-up event (for page up, we'll have to rescan)

canoncialize the selection so start <= end

find minimum y position if it starts at x1

rects array must be big enough to accommodate all characters in the given ranges

check if a utf8 string contains a prefix which is the utf16 string; if so return length of matching utf8 string

Cubic Bezier takes 4 controls points

Quadratic Bezier takes 3 controls points

-------------------------------------------------------------------------

UTF16 strings use surrogate pairs to encode codepoints >= 0x10000, so we should save the high surrogate.

Guaranteed to honor 'num_segments'

Guaranteed to honor 'num_segments'

-------------------------------------------------------------------------

Compare to detect usage errors

-------------------------------------------------------------------------

Cursor & Selection

After a user-input the cursor stays on for a while without blinking

-------------------------------------------------------------------------

-------------------------------------------------------------------------

Find window given position, search front-to-back FIXME: Note that we have an inconsequential lag here: OuterRectClipped is updated in Begin(), so wind

-------------------------------------------------------------------------

-------------------------------------------------------------------------

Window has already passed the IsWindowNavFocusable()

Retrieve list of range (2 int per range, values are inclusive)

References are only valid until a new value is added to the storage. Calling a Set***() function or a Get***Ref() function invalidates the pointer.

-------------------------------------------------------------------------

Closely mimics PathBezierToCasteljau() in imgui_draw.cpp

This is called/shared by both the stb_truetype and the FreeType builder.

Note: this is called / shared by both the stb_truetype and the FreeType builder