Function stb_text_redo

KBotExt/imgui/imstb_textedit.h:1279–1329

}

static void stb_text_redo(STB_TEXTEDIT_STRING* str, STB_TexteditState* state)
{
	StbUndoState* s = &state->undostate;
	StbUndoRecord* u, r;
	if (s->redo_point == STB_TEXTEDIT_UNDOSTATECOUNT)
		return;

	// we need to do two things: apply the redo record, and create an undo record
	u = &s->undo_rec[s->undo_point];
	r = s->undo_rec[s->redo_point];

	// we KNOW there must be room for the undo record, because the redo record
	// was derived from an undo record

	u->delete_length = r.insert_length;
	u->insert_length = r.delete_length;
	u->where = r.where;
	u->char_storage = -1;

	if (r.delete_length) {
		// the redo record requires us to delete characters, so the undo record
		// needs to store the characters

		if (s->undo_char_point + u->insert_length > s->redo_char_point) {
			u->insert_length = 0;
			u->delete_length = 0;
		}
		else {
			int i;
			u->char_storage = s->undo_char_point;
			s->undo_char_point = s->undo_char_point + u->insert_length;

			// now save the characters
			for (i = 0; i < u->insert_length; ++i)
				s->undo_char[u->char_storage + i] = STB_TEXTEDIT_GETCHAR(str, u->where + i);
		}

		STB_TEXTEDIT_DELETECHARS(str, r.where, r.delete_length);
	}

	if (r.insert_length) {
		// easy case: need to insert n characters
		STB_TEXTEDIT_INSERTCHARS(str, r.where, &s->undo_char[r.char_storage], r.insert_length);
		s->redo_char_point += r.insert_length;
	}

	state->cursor = r.where + r.insert_length;

	s->undo_point++;
	s->redo_point++;
}

static void stb_text_makeundo_insert(STB_TexteditState* state, int where, int length)
{