DrawAlignedText - draw spaced row of text between a margin

[kevin]

  DrawAlignedText - draw spaced row of text between a margin

  This example take a single line input string, splits it, works out the width of all the text fragments in pixels, then displays the text fragments so it  aligns to the edges, like you would see in a newspaper.   A newspaper is those black and white things old people read..    :)

PlayBASIC Code: [Select]

leftmargin=150
rightmargin=650

 c=$304050   
 boxc 0,0,leftmargin,getsurfaceHeight(),true,c
 boxc rightmargin,0,getsurfacewidth(),getsurfaceHeight(),true,c



   do
       message$=readdata$()
      if len(Message$)       
          DrawAlignedText(Message$,LeftMargin,RightMargin)
      else
         exitdo
      endif
   loop
   
Sync
waitkey
 



 data "Been testing an idea for a bit based z buffering"
 Data "Rows of stupid text, asdfsdf"
 data "type of simplification that could be parsed by a language"
 data "wobble zoom bump and burp"
 data ""
   

 
 
Function DrawAlignedText(T$,LeftMargin,RightMargin)

   Ypos=GetCursorY()

   Dim Frags$(255)
   count=splittoarray(t$," ",Frags$(),0)
   
   DisplayWidth=RightMargin-LeftMargin

   Count2=Count-1      

   SpaceWidth=GEtTextWidth(" ")
   for lp =0 to count2
         s$=frags$(lp)
         RawTextWidth+=GetTextWidth(S$)
   next


   Spacing#=float(DisplayWidth-RAwTextWidth)/Count2
   
   XPos#=LeftMargin
   For lp =0 to Count2
         s$=frags$(lp)
         text Xpos#,Ypos,s$
         xpos#+=GetTextWidth(s$)+Spacing#
   next
   
   SetCursorY Ypos+GetTextHeight("|")
EndFUnction

 DrawAlignedMessage

    This version is the logical extension of the previous example, except this time the render function will handle long dialog styled messages, which will wrap and each row will be aligned within the display margins.

PlayBASIC Code: [Select]

   // set our margins 
   leftmargin=150
   rightmargin=650

   // display the margin so the user can see it
    c=$304050   
    boxc 0,0,leftmargin,getsurfaceHeight(),true,c
    boxc rightmargin,0,getsurfacewidth(),getsurfaceHeight(),true,c


   // make a big long message to display
    message$="Been testing an idea for a bit based z buffering Rows of stupid text, asdfsdf type of simplification that could be parsed by a language wobble zoom bump and burp "
      message$+=message$
    message$+=message$


   // render it within this long message within the bounds
    DrawAlignedMessage(Message$,LeftMargin,RightMargin)


   // show the screen, wait for a key press and end when the user hits a key
   Sync
   WaitKey
   end   




/*
 ------------------------------------------------------------------------------
 ------------------------------------------------------------------------------
 ---[ DRAW ALIGNED MESSAGE ]---------------------------------------------------
 ------------------------------------------------------------------------------
 ------------------------------------------------------------------------------
  
   This function takes the longer input message split it up fragments and then
   rendering the text so it wraps within the user defined margins while keeping
   even spacing.
   
*/   
 
 
    type tMessageFragment
         WordPos
         WordSize         
          WidthInPixels
          Row      
    EndType
 
 

Function DrawAlignedMessage(Message$,LeftMargin,RightMargin)

   // compute the size this text should fit into
   DisplayWidth=RightMargin-LeftMargin

   // make sure there's some room between text fragments
   TrimmedDisplayWidth=DisplayWidth-16

   Dim Message(1000) as tMessageFragment


   // break this message down into list of tokens

   SearchStatus=true
   LastPos      =1
   Xpos         =0
   TokenCount   =0
   RowCount      =0
   
   SpaceWidth   =GetTExtWidth(" ")

   // -------------------------------------------------------------------------
   repeat      // split the input message and lay it out in a tokenized form
   // -------------------------------------------------------------------------

         NextPos=instring(Message$," ",LastPOs)

         if NextPOs=0
               NextPos=len(Message$)+1
               SearchDone=true
         endif

         ThisWord$=Mid$(Message$,LastPOs,NextPOs-LastPOs)

         Message(TokenCount)   = new tMessageFragment
         Message(TokenCount).WordPos  = LastPos
         Message(TokenCount).WordSize = NextPOs-LastPos

         WidthInPixels=GetTextWidth(ThisWord$)
         Message(TokenCount).WidthInPixels = WidthInPixels
         
         if Xpos+WidthInPixels+SpaceWidth>=TrimmedDisplayWidth
               Xpos=0
               RowCount++
         else
            Xpos+=WidthInPixels+SpaceWidth
         endif
         Message(TokenCount).Row = RowCount
         
               
         TokenCount++

         ; move forward
         LastPOs=NextPos +1         
   until SearchDone=true


   // Get the Pens current Ypos on the screem, so it acts like print
   Ypos=GetCursorY()

   LastPOs=0
   // -------------------------------------------------------------------------
   For Rowlp=0 to RowCount            ; RENDER ROWS 
   // -------------------------------------------------------------------------
   
         // the number of pixels that will be in this row          
         TotalWidthOfRowInPixels=0
         
         // find the end of this row up front and compute it's size in pixels
         for Searchlp=LastPos  to TokenCount-1
            ThisRow=Message(Searchlp).row
            if ThisRow=RowLP
                  NextPos=SearchLp
                  TotalWidthOfRowInPixels+=Message(Searchlp).WidthInPixels
            else
                  exitfor searchlp
            endif
         next

         
         TokensOnRow=NextPos-LastPos
   
         // compute the 
         Spacing#=float(DisplayWidth-TotalWidthOfRowInPixels)/TokensOnRow
         
         XPos#=LeftMargin
         For Drawlp =LastPos TO NextPos
               s$=mid$(MEssage$,Message(Drawlp).WordPos,Message(Drawlp).WordSize)
               text Xpos#,Ypos,s$
               xpos#+=Message(DrawLp).WidthInPixels+Spacing#
         next
         Ypos+=GetTextHeight("|")

         LastPos=NextPos+1   
   next
   

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