# Homework 4, Due in class (or email to TA) Oct 2

1. Extend the paint program presented in class as follows. Hand in the code and screendump(s) showing the new functionality. Document anything that is unclear.
3. (10) Add an entry to the permanent menu on the top to draw a circle; the user selects opposite ends of a diameter.
4. (10) Modify the program to keep drawing primitives until you select something else from the top menu. That is, after you click on line, each pair of future clicks causes another line. (Now the program ignores left clicks after the first 2 until you again select something on the top menu.)
5. (20) Modify the program to use a display list, so that the objects are redrawn when you redisplay the window. (This may be surprisingly hard.)
1. (5) Why does paint.c contain this line:
y=wh-y;
Mouse returns X and Y from the top, but OpenGL has Y measured from the bottom. You need to subtract the window height from the mouse Y value to get distance from the bottom to draw where you click.
1. (15) Assume that you have a model coordinate space with corners (-1000,-1000) and (1000,2000). You wish to map points in it to a window with corners (0,0) and (1,1). (0,500) should map to (0.5,0.5). X and Y should scale the same. Compute what the transformations for X and Y should be, in this form:
X' = s X + dx
Y' = s Y + dy
I.e., tell me what s, dx, and dy are.
del(x)=2000, del(y)=3000. => Possible scaling S=1/2000 or S=1/3000.
Choosing the lower scaling in order to maintain same scale. S=1/3000
Substituting values of coordinates in equation: 0.5=1/3000 *0 + dx ; 0.5=500/3000 + dy
dx = 0.5, dy=1/3
1. Curtis Priem is an RPI grad who founded NVIDIA and who is now on RPI's Board of Trustees. He has been a generous benefactor of RPI. He has about 200 patents worldwide.
1. (10) Check the subjects of Priem's US patents, and briefly comment on the distribution of patents by subject.
He has plenty of patents in the field of graphics but he also has patents network related patents.
  # (10) Pick a graphics-related patent, and summarize it in 100 words or so. Use your words; don't just copy the patent.

Any patent in the lists, though there were popular picks were 6282587: Method and apparatus for accelerating the rendering of images
6023738: Method and apparatus for accelerating the transfer of graphical images
A brief explanation in your own words.