PlayBASIC Tutorial: From Arrays To Types (Intro To Types) - (2018-06-12)

[kevin]

PlayBASIC Tutorial:  From Arrays To Types  (Intro To Types) - (2018-06-12)


This tutorial picks up where the previous variables to arrays tutorial left off,  in that it takes the array code, demos that code then we set about converting the parallel array approach shown in the previous tutorial and we build a structure (TYPE) to hold each characters properties.   Once the type has been defined that includes all the required properties, we then define a typed array that will house the collection of characters.    Later in the video take a look at using typed lists also.   So if your struggling with types this could be a good place to start.

Go here (variables to array tutorial  for the previous  video & source code.


To get the source code created in this video  go here:

Video:

http://playbasic.com
http://underwaredesign.com


Example #1 - Converting the Parallel Arrays To Typed Array

PlayBASIC Code: [Select]

    Setfps 20

   Number_Of_Characters = 50

   type tCharacter
         Xpos#
         Ypos#
         Xspeed#
         Yspeed#
         Colour
         Size
   endtype


   dim Characters(Number_Of_Characters) as tCharacter 

   
   for lp = 1 to Number_Of_Characters

         ;  Allocate a newe tCharacter and place it's handle
         ;  into the Character(lp) array / container at this position         
         Characters(lp) = new tCharacter
                  
         Characters(lp).Xpos  = rnd(800)
         Characters(lp).Ypos  = rnd(600)
         Characters(lp).Size  = rndrange(16,50)
         Characters(lp).Xspeed = rndrange(-5, 5)
         Characters(lp).Yspeed = rndrange(-5,5)
         Characters(lp).Colour = rndrgb()
         
   next
   
  
  //-------------------------------------------------------
  //---[ MAIN LOOP ]---------------------------------------
  //-------------------------------------------------------
   
  do 
     
        Cls rgb(0,400,20)
        
        for lp = 1 to Number_Of_Characters
           Radius = Characters(lp).Size
            x#=Characters(lp).Xpos
            y#=Characters(lp).Ypos
   

           circlec X#,Y#,Radius,true,Characters(lp).Colour
                    
           x# = wrapvalue(x# + Characters(lp).Xspeed , -Radius, 800 + Radius)
           y# = wrapvalue(y# + Characters(lp).Yspeed , -Radius, 600 + Radius)
          
           Characters(lp).xpos= x#
           Characters(lp).ypos= y#             
        next
          
        Sync
     loop

Example #2 - Converting Typed Array To Typed List

PlayBASIC Code: [Select]

   Setfps 20

   Number_Of_Characters = 50

   type tCharacter
         Xpos#
         Ypos#
         Xspeed#
         Yspeed#
         Colour
         Size
   endtype


   dim Characters as tCharacter  list 

   
   for lp = 1 to Number_Of_Characters
      
         Characters = new tCharacter
                  
         Characters.Xpos  = rnd(800)
         Characters.Ypos  = rnd(600)
         Characters.Size  = rndrange(16,50)
         Characters.Xspeed = rndrange(-5, 5)
         Characters.Yspeed = rndrange(-5,5)
         Characters.Colour = rndrgb()
         
   next
   
  
  //-------------------------------------------------------
  //---[ MAIN LOOP ]---------------------------------------
  //-------------------------------------------------------
   
  do 
     
        Cls rgb(0,400,20)
        
        for each Characters()
           
           Radius = Characters.Size
            x#=Characters.Xpos
            y#=Characters.Ypos
   

           circlec X#,Y#,Radius,true,Characters.Colour
                    
           x# = wrapvalue(x# + Characters.Xspeed , -Radius, 800 + Radius)
           y# = wrapvalue(y# + Characters.Yspeed , -Radius, 600 + Radius)
          
           Characters.xpos= x#
           Characters.ypos= y#             
        next
          
        Sync
     loop


 

[baggey]

Absolutly first class!

Love working through code like this. It's like being an apprentice again.

Sort of have an idea now as to why things are layed out this way now. Rather than remembering numbers to elements in an array. I can go straight to it with a name.

Kind Regards Bagggey