The routine gSetItalicAngle() sets the current italic angle to the value in slant. The italic angle is reduced to an equivalent angle between -90.0 and +90.0 degrees. The maximum possible magnitude of the slant is 85.0 degrees. The italic angle is measured in a clockwise direction from the character vertical.
What effect a call to gSetItalicAngle() has when characters are generated depends on the character mode at that time:
(a) gSetHardCharSize()
Call to gSetItalicAngle() has no effect
(b) gSetHardChars()
Characters may be non-italicized if not supported by the device
(c) gSetMixedChars()
Italic angle may differ by up to 5 degrees from the requested angle
(d) gSetSoftChars()
Characters are italicized exactly as requested
(e) gSetCharTransformMode(GON)
Characters are italicized as requested and transformed, so angle may be modified by current shear.
