``` Tinker Toys
```

Tinker Toys Online Bibliography and Glossary

Bibliography

FOLE94
James Foley, Andries van Dam, Steven Feiner, John Hughes, and Richard Phillips, Introduction to Computer Graphics, Addison-Wesley, Reading, MA, 1994.

Glossary

back clipping plane
The plane, parallel to the view plane, that specifies the back of the view volume. Points with a VRC n-value less than the back clipping plane n-value will be not be visible in the view window.
Introduction to Computer Graphics, p204

A parallel projection view volume truncated by the front and back clipping planes. DOP is the direction of projection.
Introduction to Computer Graphics, p204

back distance (B)
The signed value that represents the distance of the back clipping plane from the VRP measured along the VPN, with positive values in the direction of the VPN.
Introduction to Computer Graphics, p204

front clipping plane
The plane, parallel to the view plane, that specifies the front of the view volume. Points with a VRC n-value greater than the front clipping plane n-value will be not be visible in the view window.
Introduction to Computer Graphics, p204

A perspective projection view volume truncated by the front and back clipping planes.
Introduction to Computer Graphics, p205

front distance (F)
The signed value that represents the distance of the front clipping plane from the VRP measured along the VPN, with positive values in the direction of the VPN.
Introduction to Computer Graphics, p204

projection reference point (PRP)
The point, specified in VRC system coordinates, where the view originates. Objects are "seen" by looking through the PRP toward the center of the view window.
Introduction to Computer Graphics, p203

A parallel orthographic projection. The direction of projection is the vector from the PRP to the center of the view window, and is parallel to the VPN. The shear-parallel matrix would be equal to the identity matrix in this case.
Introduction to Computer Graphics, p204

A perspective projection. The direction of projection for any given point is the vector from the PRP to that point.
Introduction to Computer Graphics, p202

shear-parallel matrix
The matrix, used in creating the view of an object, that shears the view volume such that the direction of projection becomes parallel to the z-axis. It is applied after the view-orientation matrix and adjusts the view for a PRP that is not lined up with the view window center along the VRC n-axis.
Introduction to Computer Graphics, p218

view-orientation matrix
The matrix which transforms points represented in world coordinates into their VRC equivalent. It translates the VRP to the origin and then rotates the VRC so its u, v and n axes align with the world-coordinate system x, y and z axes, respectively.
Introduction to Computer Graphics, p205, 218

view-plane normal (VPN)
A normal to the view plane. The VPN defines the VRC n-axis. It is specified in world coordinates.
Introduction to Computer Graphics, p201

view reference point (VRP)
The point in world coordinates which defines the VRC origin.
Introduction to Computer Graphics, p201

view-up vector (VUP)
The vector which determines the VRC v-axis direction. It is specified in world coordinates.
Introduction to Computer Graphics, p202

The VRC v-axis is defined by the projection of the VUP parallel to the VPN onto the view plane.
Introduction to Computer Graphics, p202

view volume
The portion of the world that is projected onto the view plane. Only objects which are in the view volume are visible in the view window.
Introduction to Computer Graphics, p203

view window
A window in the view plane bounded by the VRC (umin, vmin) and (umax, vmax) points. These points are listed as VWmin and VWmax in the View Control Window.
Introduction to Computer Graphics, p203

The view window as it sits in the view plane. Note: The view window center does not have to be equal to the VRP.
Introduction to Computer Graphics, p202

viewing-reference coordinate (VRC) system
The right-handed, (u, v, n) coordinate system that specifies how the world is viewed. Viewing parameters are defined in VRC system coordinates.
Introduction to Computer Graphics, p202

The VRC origin is the VRP. It's n-axis is defined by the VPN. It's u-axis direction is the vector cross product of the VUP and VPN. And it's v-axis is the vector cross product of its z-axis (the VPN) and its x-axis.
Introduction to Computer Graphics, p202

world-coordinate (WC) system
The infinite, right-handed, (x, y, z) coordinate system that is centered at the origin. A point's WC location is its absolute position. All other coordinate systems are defined in relationship to the world-coordinate system.
Introduction to Computer Graphics, p180, 190