HW4: Automatic Landscape

Many aspects of backgrounds and landscapes that you see in today's movies are computer enhanced. Perhaps the weather was wrong on the day the film was shot, or maybe the director had a change of mind involving the mood. For this assignment, you will create an image that can be changed and adjusted by the user.

Create a directory named landscape1 to store your work, then copy into it the graphics.py library that we used last time. Write Python code to make a canvas of size 500 pixels wide and 700 pixels high, then draw a simple landscape. Your landscape doesn't have to be particularly fancy. Set the background to blue to represent a sky, then draw a couple of rough hills or buildings using ovals or rectangles. Make sure you have a nice big sky.

Draw a small white cloud at the top left corner off your canvas. Your cloud can be as simple as a cloud-sized oval, but feel free to use multiple overlapping ovals or other techniques to make your cloud as attractive as you like.

The goal of this part of the assignment is to place the cloud in different places in the sky, depending on where the user of your program wants it.

Specifically, your program should ask your user for a wind speed (in miles per hour), and the number of hours that have passed since the cloud first appeared in the top left of the window. Your program should then draw the cloud in its correct location. Assume that the image is 20 miles across, and that the wind is blowing directly to the right.

Here is a sample of what the interaction between your program and your user should look like. The user's responses are in red, with a dotted underline, so that you can tell what the user has typed. (In reality, though, this should appear in the same color as all the other text in your terminal window.)

Automatic Landscape Builder

What is the windspeed in miles per hour? 3.5
How many hours have passed? 2.5

Here is your picture!

The program would then show the user a picture, with the cloud in the correct place, according to the user's input.

You will need to do some arithmetic to determine precisely where the cloud should go:

• If you divide the number of pixels across by the number of miles across, this will tell you how many pixels are in a mile.
• If you multiply the wind speed times the number of hours that have passed, this will tell you how many miles the cloud has traveled.
• If you multiply the number of miles that the cloud has traveled by the number of pixels in a mile, this will tell you the number of pixels in the image that the cloud has traveled.
• After you have figured out the number of pixels that that the cloud has traveled, you have to round it off to an integer. (A cloud cannot start at half a pixel.) Here is sample code that does rounding:

      num1 = 3.2
      num2 = round(num1)
      

Here are some things you can do to test your code:

• If windspeed = 20 and hours = 0.5, the left side of the cloud should appear halfway across the window.
• If windspeed = 10 and hours = 1, the left side of the cloud should appear halfway across the window.
• If windpseed = 10 and hours = 1.5, the left side of the cloud should appear 3/4 of the way across the screen.

Finally, begin thinking about good style for your programs. You should make them as readable as possible for someone else trying to understand them. At a minimum, you should use comments at the top of your program indicating your name(s), and use comments above consecutive portions of Python code explaining what they do.