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DCL:GRPH1:Summary:3-D Normalization Transformation

1.5.3 Settings for Coordinate Systems

To draw graphics in a 3-D UC, as in the 2-D coordinate system, the parameters that determine transformation function must be specified after calling SGFRM but before starting to draw graphics. The values of these parameters become effective by calling the routine SCSTRF, which makes the transformation function effective. The parameters for 3-D systems are independent of those for the 2-D system.

The main parameters are all handled by SGpGET/SGpSET, but since it is cumbersome to set the parameters for transformation function individually, a routine is available for setting the parameters at once, which is usually used.

To set transformation parameters, the following coding is performed after SGFRM.

Rectangular Coordinate

 

       CALL SCSVPT(VXMIN3, VXMAX3, VYMIN3, VYMAX3, VZMIN3, VZMAX3)

       CALL SCSWND(UXMIN3, UXMAX3, UYMIN3, UYMAX3, UZMIN3, UZMAX3)

       CALL SCSTRN(ITR3)

       CALL SCSTRF

Cylindrical Coordinate, Spherical Coordinate

     CALL SCSORG(SFAC3, VXORG3, VYORG3, VZORG3)

     CALL SCSTRN(ITR3)

     CALL SCSTRF