CS 3723  Programming Languages
Recitation 12. Postscript
Week 13: Apr 15 - 17

Submit following directions at: submissions and rules at: rules. Deadlines are: 2014-04-29  23:59:59 (that's Tues, 29 Apr 2014, 11:59:59 pm) for full credit. No 75% credit deadline.

Part A: Return Address for a mailing

For full credit, include the following features:

• the two fields shown must be exactly 0.5 inch (36 points) from the top of an 8.5-by-11 inch sheet of paper,
• margins must be exactly 0.5 inch (36 points).
• The font on the left should be given by Times-Bold findfont 14 scalefont setfont
• The font on the right should be the same, except 12 point
• all linewidths should be given by 2 setlinewidth.
• The length of the lines at the left should be the same as (The University of Texas at San Antonio) stringwidth pop, that is, by the length of this string.
• lines on the left should be 15 points apart vertically.
• lines on the right should be 12 points apart vertically.
• The box on the right should be 132 points wide.
• Each line of the box on the right should be exactly centered in the middle of the box. (See the page Right Justifying Text, which also mentions centering text, a similar task.)

The image above is an actual image, 8.5 inches wide, taken from a program that met the requirements above. If you have trouble meeting the above requirements, just fake it as well as you can, and try to make your output look as close to the above as possible.

x y r 0 360 arc stroke

[The above code does paint a circle, but in general it's a good idea to stick a  newpath  in at the beginning.]

You are to write a Postscript program that will draw an array of n circles, each of radius r and the centers of these circles should be arranged around a central point in a circle of radius s. These parameters should be variables in your program:

• n: the number of circles
• r: the radius of each circle
• s: the radius of the circle giving the centers of the circles.

The pictures below give a little more information: In the last 4 pictures the first circle is drawn wider and in red. The circle of the centers of circles is drawn in "CornflowerBlue".

Part B: Circles
n:10, r:100, s:100	n: 20, r:100, s:100	n: 40, r:100, s:100
n:40, r:50, s:150	n: 20, r:150, s:50	n: 30, r:110, s:90

Implementation: There are several simple ways to program this in Postscript. You should center everything at the origin, translate to the center of the page, and draw everything.

You can let an angle th take on the necessary successive values. Then the center of each circle of radius r will be at the point (s*cos(th), s*sin(th), and you can draw each circle.

Alternatively, you can draw one circle and keep rotating by the successive angle: 360/n.

However, this is not an art assignment, and you are not being graded on "good graphic design." Instead I want you to experiment with complicated Postscript code to help learn the language. Here are items I want you to include in the recitation:
1. The initial card should be exactly 4 inches by 7 inches. (That is, the card should be exactly 288 points by 504 points.)
2. The outer 4 inch by 7 inch boundary should be stroked with a line of width 3 points.
3. With one run, translating the card if necessary, print a single copy of your card on a sheet of paper. Again, this should be 4 inches by 7 inches.
4. In a separate run, using a scale factor of 0.5 in each direction, produce at least 5 copies of the same card at half size, that is, of size 2 inches by 3.5 inches. The Postscript code that produces these 5 copies should employ a Postscript loop. (See pages 51-52 and Chapter 7 of the Blue Book (PDF, 847k).)
5. At least one piece of text on the card should either be centered or right justified, using the stringwidth function, so that the text would remain centered or right-justified even if the font size is changed. (See the Blue Book, pages 42-43 for right justification, and pages 58-59 for centering. See also my handout with a card on it.)

Here are some additional features that I would like to see you incorporate into your card:

6. The use of some ``graphic object'', e.g., some picture made up of one or more paths. For example, a recursive structure like that on pages 73-75 of the Blue Book would be interesting.
7. Use some color, although your final printout doesn't have to be on a color printer.
8. The use of an outline around characters in a string. (See the example on page 98 of the Blue Book.)
9. The use of a clipping path. (See the Blue Book, pages 103-104.)

Finally, try to make it look interesting. Be creative. The card doesn't have to have your real name. Don't copy the book or one another or my cards below. (Some students might submit, say, exactly the "Diamond Cafe" card below with different words stuck it. This would be worth little or no credit.)

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Examples of Cards: Two cards from the Blue Book plus one of my own:

• The Diamond Cafe on pages 41-45: .html, .ps, .pdf.
• Omaha (actually a logo) on pages 57-59: .html, .ps, .pdf.
• Here is one of my own cards: .html, .ps, .pdf.
• Here is another card of my own: .pdf.