Does applying an perspective matrix preserve parallel lines?
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Does applying an orthographic matrix preserve parallel lines? (i.e. parallel lines in input map to parallel lines in output)
A. Yes
B. No
Consider a modified orthographic projection matrix:\( \left( \begin{array}{cccc} \frac{2}{r-l} & 0 & 0 & -\frac{r+l}{r-l}\\ 0 & \frac{2}{t-b} & 0 & -\frac{t+b}{t-b}\\ 0 & 0 & \mathbf{\frac{2}{f-n}} & -\frac{f+n}{f-n}\\ 0 & 0 & 0 & 1 \end{array} \right) \)When would we use such a matrix instead of the normal glOrtho?
A. When we wish to tilt our camera.
B. When we wish to view along a direction not aligned with an axis.
C. When the far plane is closer than the near plane.
D. When we define our coordinate system so that we are looking down a positive axis.
E. The results are unpredictable.
Given a R2 point defined on the canonical x,y axis, i⃗ =(22), what are the coordinates in a new coordinate system with the origin at j⃗ =(11), and axes at 45 degrees? (The rotated first axis will be aligned to (11) in an unrotated coordinate system, with an origin at j⃗ ). Denote this changed vector as k⃗ Enter your answers as numbers.kx=?______ ky=?______
The gluLookAt matrix can be summarized as:
A. Scaled followed by Translation followed by Rotation
B. Rotation followed by Scale followed by Translation
C. Translation followed by Rotation
D. Rotation followed by Translation
E. None of the above.