Roku Developer Program

[cheungj]

Has anyone encountered an issue with roFont.getOneLineWidth(string, max size) not returning the right width for a particular string for specific fonts

essentially what I have is an image canvas with a layer that has a piece of text that is only suppose to be on one line. the font is set but the fontsize is dynamic.

so for a particular font size say 50 what happens is when i use the roFont.getOneLineWidth it returns a rectangle width which is smaller then it is to fit the text on one line so it word wraps. has anyone encountered an issue like this with that method before?

[destruk]

Yes, if the area you are writing your text to is too narrow to fit on one line, it wraps the text to fit, so if you check the height value as well you can get the actual size/area it is using. You can avoid the issue by using a fixed-width font instead of proportional, and using a set font size instead of a variable font size selection, and that way you could simply count the number of standard characters you have in the line rather than checking width and individual character metrics.

[RokuMarkn]

Destruk, I don't think that's the case. ifFont.GetOneLineHeight takes no parameters so it can't return the height of a specific wrapped string. GetOneLineWidth also doesn't take any wrapping into account. I'm not aware of any cases where GetOneLineWidth would return less than the space required to draw the string as one line, unless it's larger than the MaxWidth parameter. Can you provide an example?

--Mark

[destruk]

I was using .Size.W and .Side.H for that.
Maybe getonelinewidth and getonelineheight is handled differently.

[cheungj]

Certainly I have example right here

fontsize is dynamic integer
Stringvalue = "Hello foo foo enjoy"

font = m.fonts.GetFont("BPreplay",fontSize,true,false)
txtRect.w = font.GetOneLineWidth(stringvalue, canvas.w*2)

so when i print out the txtRect.w its smaller then what the text requires to fit on oneline. Should I provide an offset so it has additional padding or space?

[RokuMarkn]

Ok, I tried these commands in the debugger:

BrightScript Debugger> reg = CreateObject("roFontRegistry")
BrightScript Debugger> font = reg.GetDefaultFont()
BrightScript Debugger> s = "Hello foo foo enjoy"
BrightScript Debugger> w = font.GetOneLineWidth(s, 10000)
BrightScript Debugger> ?w
 336
BrightScript Debugger> screen = CreateObject("roscreen")
BrightScript Debugger> screen.DrawText(s, 100,100,&hffffffff,font)
BrightScript Debugger> screen.DrawRect(100,140,336,32, &hffff00ff)
BrightScript Debugger> screen.Finish()

This drew the text and then drew a yellow rectangle that exactly matches the width of the text, so it seems to be working here. Can you reproduce your problem with the default font? If not, perhaps there is a problem with your font file. If you can reproduce with the default font, please post the complete source.

--Mark

[greubel]

I've been having a lot of problems trying to get text to fit with roImageCanvas.
I coded this up for roImageCanvas not roScreen, which is what cheungj asked about.

It appears the Default font on HD is "Large" but not on SD displays. I even tried "Huge" but it still didn't fill the rectangle.
"GetOneLineWidth" looks close for HD BUT no where near on SD displays.

   reg = CreateObject("roFontRegistry")

   scr = CreateObject("roImageCanvas")
   port = CreateObject( "roMessagePort" )
   scr.SetMessagePort( port )

   scr.SetLayer( 0, { color: "#FF808080" } )
   scr.Show()

   s = "Hello foo foo enjoy"
   font = reg.GetDefaultFont()
   w = font.GetOneLineWidth( s, 10000 )
   h = font.GetOneLineHeight()
   size = "Large"
   txt = "w = "+w.ToStr()+" h = "+h.ToStr()+" "+size

   items  = CreateObject( "roArray", 100, 1 )
   items.Push( { color: "#FFFFFFFF", TargetRect:{x:100,y:100,w:w,h:h}} )
   items.Push( { Text:s,
         TextAttrs:{ Color:"#FFFF0000", Font:size, HAlign:"Left", VAlign:"Middle" },
         TargetRect:{ x:100,y:100,w:w,h:h }} )
   items.Push( { Text:txt,
         TextAttrs:{ Color:"#FF000000", Font:"Large", HAlign:"Left", VAlign:"Middle" },
         TargetRect:{ x:100,y:50,w:600,h:60 }} )
   scr.SetLayer( 1, items )

Results SD

Results HD

[greubel]

It appears there are more problems with "getOneLineWidth".
It does not take into account the font face, bold or italic, which causes text wrapping.
Plus the results are different for SD and HD displays for the same size default font.

What is the algorithm for determining the length for the string ?

[RokuMarkn]

Could you clarify what you mean by "It does not take into account the font face, bold or italic"? This example shows that it returns different results when bold is used:

BrightScript Debugger> reg = CreateObject("roFontRegistry")
BrightScript Debugger> font1 = reg.GetDefaultFont(32,false,false)
BrightScript Debugger> font2 = reg.GetDefaultFont(32,true,false)
BrightScript Debugger> ?font1.GetOneLineWidth("this string", 10000)
 146
BrightScript Debugger> ?font2.GetOneLineWidth("this string", 10000)
 166

I will look into the issue with SD.

--Mark

[greubel]

It does. What I'm saying is that using that value will cause the text to wrap. Which makes it useless.
Working a a test routine, will post it soon.