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TextWidth - strange on Mac OS :-)

https://www.purebasic.fr/english/viewtopic.php?t=69615

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TextWidth - strange on Mac OS :-)

Posted: Sat Nov 11, 2017 9:29 pm
by walbus
Try this, it took me a while to realize what was going on :twisted: LOL

Code: Select all

CreateImage(1, 100, 100)
StartDrawing(ImageOutput(1))
Debug TextWidth("Hello World")
Debug TextWidth("H")+TextWidth("e")+TextWidth("l")+TextWidth("l")+TextWidth("o")+
      TextWidth(" ")+TextWidth("W")+TextWidth("o")+TextWidth("r")+TextWidth("l")+TextWidth("d")
StopDrawing()

Re: TextWidth - strange on Mac OS :-)

Posted: Sat Nov 11, 2017 11:38 pm
by J. Baker
I'm missing something? Debug...
64
64

Re: TextWidth - strange on Mac OS :-)

Posted: Sat Nov 11, 2017 11:55 pm
by walbus
J. Baker, your result looks OK
Its strange...

On Win and Linux i get for this sample above both values equal (PB561)
On Mac OS 10.12 -10.13 i get 61 55 (PB 561)
With any text, the difference is approximately one character width

I am sure, different users can confirm it

The question is, what is the reason ?

Re: TextWidth - strange on Mac OS :-)

Posted: Sun Nov 12, 2017 6:22 am
by davido
@walbus,
My system: MacBook Pro
System Version: OS X 10.10.5 (14F2511)
Kernel Version: Darwin 14.5.0

PureBasic 5.61 x64
Debugger wrote: 61
55

Re: TextWidth - strange on Mac OS :-)

Posted: Sun Nov 12, 2017 9:19 am
by walbus
@davido Many thanks for confirming

Meanwhile, I assume a PB bug
I post it in the Bug forum, now
It can be very unpleasant and strange for text length calculations

Code: Select all

CreateImage(1, 300, 100)
OpenWindow(1, 0, 0, 300, 100, "", #PB_Window_SystemMenu | #PB_Window_ScreenCentered)
StartDrawing(ImageOutput(1))
Debug TextWidth("Hello World")
twidth=TextWidth("H")+TextWidth("e")+TextWidth("l")+TextWidth("l")+TextWidth("o")+
       TextWidth(" ")+TextWidth("W")+TextWidth("o")+TextWidth("r")+TextWidth("l")+TextWidth("d")
Debug twidth
Box(0, 0, twidth, 20, $FF)
DrawText(0, 0, "Hello World")
StopDrawing()
ImageGadget(1, 0, 0, 0, 0, ImageID(1))
Repeat : Until WaitWindowEvent()=#PB_Event_CloseWindow

Re: TextWidth - strange on Mac OS :-)

Posted: Sun Nov 12, 2017 2:14 pm
by #NULL
i have no mac but the same problem on linux

Code: Select all

CreateImage(1, 100, 100)
StartDrawing(ImageOutput(1))
  Debug TextWidth("Hello World")
  Debug TextWidth("H")+TextWidth("e")+TextWidth("l")+TextWidth("l")+TextWidth("o")+
        TextWidth(" ")+TextWidth("W")+TextWidth("o")+TextWidth("r")+TextWidth("l")+TextWidth("d")
StopDrawing()

Debug ""

LoadFont(0, "arial", 12)

CreateImage(1, 100, 100)
StartDrawing(ImageOutput(1))
  DrawingFont(FontID(0))
  Debug TextWidth("Hello World")
  Debug TextWidth("H")+TextWidth("e")+TextWidth("l")+TextWidth("l")+TextWidth("o")+
        TextWidth(" ")+TextWidth("W")+TextWidth("o")+TextWidth("r")+TextWidth("l")+TextWidth("d")
StopDrawing()

Debug ""

CreateImage(1, 100, 100)
StartDrawing(ImageOutput(1))
  DrawingFont(#PB_Default)
  Debug TextWidth("Hello World")
  Debug TextWidth("H")+TextWidth("e")+TextWidth("l")+TextWidth("l")+TextWidth("o")+
        TextWidth(" ")+TextWidth("W")+TextWidth("o")+TextWidth("r")+TextWidth("l")+TextWidth("d")
StopDrawing()
96
97

84
84

96
97
seems to happen only with the default font.
ubuntu 16.04, pb 5.61 x64

Re: TextWidth - strange on Mac OS :-)

Posted: Sun Nov 12, 2017 2:38 pm
by Wolfram
I get always the same result.
Can you try the example?

Code: Select all

CreateImage(1, 100, 100)
StartDrawing(ImageOutput(1))
  Debug TextWidth("Hello World")
  Debug TextWidth("H")+TextWidth("e")+TextWidth("l")+TextWidth("l")+TextWidth("o")+
        TextWidth(" ")+TextWidth("W")+TextWidth("o")+TextWidth("r")+TextWidth("l")+TextWidth("d")
StopDrawing()

Debug ""

LoadFont(0, "Andale Mono", 12) ; has fix tracking

CreateImage(1, 100, 100)
StartDrawing(ImageOutput(1))
  DrawingFont(FontID(0))
  Debug TextWidth("Hello World")
  Debug TextWidth("H")+TextWidth("e")+TextWidth("l")+TextWidth("l")+TextWidth("o")+
        TextWidth(" ")+TextWidth("W")+TextWidth("o")+TextWidth("r")+TextWidth("l")+TextWidth("d")
StopDrawing()

Debug ""

CreateImage(1, 100, 100)
StartDrawing(ImageOutput(1))
  DrawingFont(#PB_Default)
  Debug TextWidth("Hello World")
  Debug TextWidth("H")+TextWidth("e")+TextWidth("l")+TextWidth("l")+TextWidth("o")+
        TextWidth(" ")+TextWidth("W")+TextWidth("o")+TextWidth("r")+TextWidth("l")+TextWidth("d")
StopDrawing()

Re: TextWidth - strange on Mac OS :-)

Posted: Sun Nov 12, 2017 3:02 pm
by walbus
Yep, on Linux Mint 18 x64/x86
96
97

110
110

96
97

On Win 10 all equal

On Mac 10.12 - 10.13
61
55

79
77

61
55

Stretched text looks so (Stretch factor here x=7, y=7, output from a demo code) :
Image

Re: TextWidth - strange on Mac OS :-)

Posted: Sun Nov 12, 2017 5:37 pm
by J. Baker
What's your default font? Maybe it's not mono spaced?

Re: TextWidth - strange on Mac OS :-)

Posted: Sun Nov 12, 2017 6:14 pm
by Wolfram
J. Baker wrote:What's your default font? Maybe it's not mono spaced?
Thats why I ask to tested with my example. This use a fix tracking size.
http://www.purebasic.fr/english/viewtop ... 09#p514809

Re: TextWidth - strange on Mac OS :-)

Posted: Sun Nov 12, 2017 7:13 pm
by Josh
I think that depends on the font. It is not said that two separate characters result in the same width as the two same characters together.

https://en.wikipedia.org/wiki/Kerning

Re: TextWidth - strange on Mac OS :-)

Posted: Sun Nov 12, 2017 7:51 pm
by Wolfram
Josh wrote:I think that depends on the font. It is not said that two separate characters result in the same width as the two same characters together.

https://en.wikipedia.org/wiki/Kerning
Yes, and to be sure that this is the problem here use my example code please.
I use a fond which does't use kerning.

Re: TextWidth - strange on Mac OS :-)

Posted: Sun Nov 12, 2017 8:18 pm
by davido
@Wolfram,
I ran your code and got the following results:
Debug wrote:61
55

79
77

61
55
My system: MacBook Pro
System Version: OS X 10.10.5 (14F2511)
Kernel Version: Darwin 14.5.0

PureBasic 5.61 x64

Re: TextWidth - strange on Mac OS :-)

Posted: Sun Nov 12, 2017 10:07 pm
by Dude
J. Baker wrote:What's your default font? Maybe it's not mono spaced?
I already mentioned fonts and kerning in this other thread: http://www.purebasic.fr/english/viewtop ... 24&t=69616

That's the problem with discussing the exact same thing in two threads: the answers go everywhere. One of these threads should be deleted.

As for the issue being Mac-specific, I just read on Wikipedia:
Wikipedia wrote:Apple has however extended the kern table with more complex features, including contextual and class-based kerning
So that may explain why the issue appears on iOS and not Windows/Linux?

Re: TextWidth - strange on Mac OS :-)

Posted: Sun Nov 12, 2017 10:44 pm
by Wolfram
You can try these cocoa example. It returns always 64.0 here.

Code: Select all

Procedure stringWidth(string.s)
NSSize.NSSize
FontSize.CGFloat = 12.0

NSFont = CocoaMessage(0,0, "NSFont fontWithName:$", @"Andale Mono", "size:@", @FontSize)
NSDictionary = CocoaMessage(0, 0, "NSDictionary dictionaryWithObject:",  NSFont, "forKey:$", @"NSFontAttributeName")
NSString = CocoaMessage(0, 0, "NSString stringWithString:$", @string)
CocoaMessage(NSSize, NSString, "sizeWithAttributes:", NSDictionary)

ProcedureReturn NSSize\width

EndProcedure


Debug stringWidth("Hello World")

Debug stringWidth("H") +stringWidth("e") +stringWidth("l") +stringWidth("l") +stringWidth("o") +stringWidth(" ") +
      stringWidth("W") +stringWidth("o") +stringWidth("r") +stringWidth("l") +stringWidth("d")
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