OpenGL glScaled or glScaledf problem

OpenGL OpenGL: Basic Coding
1

How do I stop is so that when the tly goes below zero everything doesn’t turn upside down.

if (tly < 0)
{
	glScalef(tly / 4, tly / 4, 0);
	b.DrawBarChart(*columnHeadChar0, *columnHeadChar1, *columnHeadChar2, *columnHeadChar3, *columnHeadChar4, *columnHeadChar5,
		columnTotal0, columnTotal1, columnTotal2, columnTotal3, columnTotal4, columnTotal5, 400, tlx, tly);
}
else
{
	glScalef(tly / 4, tly / 4, 0);
	b.DrawBarChart(*columnHeadChar0, *columnHeadChar1, *columnHeadChar2, *columnHeadChar3, *columnHeadChar4, *columnHeadChar5,
		columnTotal0, columnTotal1, columnTotal2, columnTotal3, columnTotal4, columnTotal5, 400, tlx, tly);
}
2

By not going below zero. What do you expect a negative scale factor to do?

Also, bear in mind that if an odd number of dimensions (i.e. 1 or 3) have a negative scale factor, the result will also be inside-out, so front faces will become back faces and normals will point inside rather than outside.