Proj #14 - BASIC Part II

Introduction

Since this is a creative assignment, it is not as specific as other projects. However this could be fun. My advice is to try some things, and then save your work, and then try other things, so if you don't like your changes, you can `roll back' to a previous version of your ideas.

Project : Draw a screen animated picture and accompanying "music" or sound effects.

Music is in quotation marks because some of may not be able to write a simple tune, and you will not be penalized for that.  Consider using sound effects instead of music: bird sounds or sirens can be made with several loops one after the other.

This will be more practice with looping using the following BASIC statements:

FOR... NEXT, COLOR, LINE, CIRCLE, PAINT; SOUND, GOSUB ...RETURN

For the ear to perceive constant distances between notes, the frequencies perceived be in constant ratio. That together with the fact that two notes with the frequency doubled sound `the same,' allows us to conclude that each note has a frequency that is 2^(1/12) times the frequency of the previous note.

Example Programs That Use Sound or Animation:

1. PROG 1: SCREEN 9 ' Drawing and Erasing
   COLOR 10, 1 ' Corco foreground, background ' +++ Colors +++ ' 1 = dark Blue, 2 = green, 3 = light blue, 4 = red ' 5 = purple, 6 = yellow, 7 = white, 8 = dark purple
   FOR x = 100 TO 300 STEP 15
   y = x GOSUB EraseCircle: GOSUB DrawCircle: NEXT
   END

2. DrawCircle: CIRCLE (x, y), 25, 3
   PAINT (x, y), 4, 3
   RETURN

3. EraseCircle: PAINT (x, y), 0
   RETURN

4. PROG 2: SCREEN 9 ' Falling Ball
   COLOR 10, 1 ' Corco foreground, background
   FOR x = 200 TO 300 STEP 2
   GOSUB DrawCircle: y = (x - 200) ^ 2 / 20
   GOSUB EraseCircle: NEXT
   END

   
   

5. PROG 3: SCREEN 9
   COLOR 10, 1 ' corco foreground, background
   FOR x = 200 TO 300 STEP 2
   GOSUB DrawCircle: y = (x - 200) ^ 2 / 30
   GOSUB EraseCircle: SOUND 500, .3
   NEXT BEEP
   FOR xX = 300 TO 200 STEP -2
   GOSUB DrawCircle: x = 600 - xX y = (xX - 200) ^ 2 / 30
   GOSUB EraseCircle: SOUND 1900, .3
   NEXT
   END
   

6. PROG 4:
   SCREEN 9
   COLOR 10, 1
   PLAY "mb c c g g a a g. f f e e d d c " ' . is 1.5* note duration ' fall down
   FOR x = 200 TO 300 STEP 2
   GOSUB DrawCircle: y = (x - 200) ^ 2 / 40
   GOSUB EraseCircle:
   NEXT ' bounce up
   FOR xX = 300 TO 200 STEP -2
   GOSUB DrawCircle: x = 600 - xX y = (xX - 200) ^ 2 / 40
   GOSUB EraseCircle:
   NEXT
   FOR xX = 200 TO 300 STEP 2
   GOSUB DrawCircle: x = xX + 200 y = (xX - 200) ^ 2 / 40
   GOSUB EraseCircle: NEXT
   END