Set_Handedness

Functions

void Set_Handedness (const char *value)
 Changes the Cartesian world coordinate system from "left-handed" to "right-handed" and back again. More...
 
void UnSet_Handedness (void)
 Removes all settings established by a previous call to Set_Handedness(). More...
 

Detailed Description

Function Documentation

◆ Set_Handedness()

void Set_Handedness ( const char *  value)

Changes the Cartesian world coordinate system from "left-handed" to "right-handed" and back again.

Parameters
value- Special constant—either "left" or "right". Uppercase versus lowercase does not matter; trailing blanks do not matter.

DETAILS

A "left-handed" Cartesian coordinate system is one in which, if you curl the fingers of your left hand from the X axis towards the Y axis, your thumb will point in the direction of the Z axis. This means your viewing camera is set up so that your X axis points to the right on the screen and the Y axis points straight up, then the Z axis will go into the screen.
A "right-handed" coordinate system is just the same, except that Z axis will be in the direction of your right hand's thumb. If the camera is set up with X and Y as above, the Z axis will point out of the screen.
To leave the X and Y axes alone, you're going to have to move the Camera. The default Camera is located at (0.0, 0.0, -5.0), with the up vector in the direction of (0.0, 1.0, 0.0), and aimed at (0.0, 0.0, 0.0). If you change to right-handed coordinates without touching the camera position, you will end up with the Z -axis going into the screen (since your camera is still sitting at negative Z looking towards positive Z). The Y -axis is still pointing up (because of the explicit Up Vector), and the X -axis is pointing to the left. You can change the camera position to (0.0, 0.0, +5.0), or some other suitable location, so that the X -axis will be to the right on the screen.

NOTES

Computer graphics has traditionally used a left-handed coordinate system, and this is the HOOPS default. Most other fields of science and engineering have traditionally used a right-handed coordinate system. It makes no difference except in the final screen display.
Reversing the handedness also changes the left-right sense of Dolly_Camera() , Orbit_Camera() , Pan_Camera() , Rotate_Object() , Translate_Object() , and the "polygon handedness" Heuristic. The relevant manual pages should be read appropriately.

RESTRICTIONS

See also
Set_Camera_Position, Set_Camera_Up_Vector, Set_Camera, Show_Handedness, Show_Net_Handedness, PShow_Net_Handedness.

◆ UnSet_Handedness()

void UnSet_Handedness ( void  )

Removes all settings established by a previous call to Set_Handedness().

DETAILS

No additional details. See Set_Handedness()