Color definition

[Frank Kestens]

Someone in this forum knows how to transform the RGB(x,y,z) color to a ...% needed for colordefinition ?

[Eddy Van Esch]

You mean "%" as in a 16 bits integer ?
x, y, z are each 8 bits, that makes 24 bits ....

The PB RGB() function returns a 32 bits long ...

Kind regards

[Michael Mattias]

%MYCOLOR = RGB(myRed, mygreen, myblue)

If that doesn't work (but I think it does)...try ...

%MYCOLOR =   &h00rrggbb

.. that I have exactly zero faith that I have the bytes ordered correctly but you get the idea.

If "%EQUATE= RGB(red, blue, green)" does not work, I know I have previously submitted a NFS to make it supported. BUt you can send it in too; the more who ask, the more likely the NFS will be adopted, or so they say.

MCM

[Michael Mattias]

Or, you could just reverse-engineer these..

' -------------------------------------------------
'  MACROS TO GET R, G, B values from RGB dword
' -------------------------------------------------
MACRO mGetRed   (Rgbvalue)  = Rgbvalue AND &h0FF
MACRO mGetGreen (rgbvalue)  = (Rgbvalue AND &h0FF00)   \ &h100
MACRO mGetBlue  (rgbvalue)  = (rgbvalue AND &h0FF0000) \ &h10000

[Frank Kestens]

color description

Thanks both of you !
I'll try.
BTW another feature which is interesting to have is arctg2(y;x) instead of arctg(x) , which returns values between 0-2pi instead of ...

[Michael Mattias]

Duh. This will ALWAYS work:

' custom color for this application
%MYRED       = 5
%MYGREEN    = 110
%MYBLUE      = 77
MACRO MyColor = RGB(%MYRED, %MYGREEN, %MYBLUE) 
...

  hBrush = CreateSolidBrush (MyColor)

That HAS to work.

[Pierre Bellisle]

Nuance...

[William Burns]

MCM was correct about using the &H0 method, but the order is wrong. I use this format: &H0bbggrr (where bb is the blue value in Hex format, gg=green, rr=red )

Or if you just want something that can calc the value for you to hard code in to a program, I set this small tool up several years back (it is even kinda fun to watch and play with)

http://www.powerbasic.com/support/pb...ad.php?t=23678

There is also a handy button to copy the values to the clipboard so you can easily paste them in your programs.

[Erik Christensen]

Frank,

I think you could use the following WinAPI macros, which retrieve intensity values for the blue, green and red components, respectively, of a 32-bit red, green, blue (RGB) value:

GetRValue
GetGValue
GetBValue

The values you obtain are in the range 0-255. Dividing by 255 and multiplying by 100 would give percentage.

Here is some more information on colors:

http://msdn2.microsoft.com/en-us/library/bb980062.aspx

Best regards,

Erik

[Eddy Van Esch]

... would give percentage.

Ah, he meant 'percentage' with '..%' ... I thought he meant a 16 bit integer variable by it ..

[Aldo Vitagliano]

Thanks both of you !
I'll try.
BTW another feature which is interesting to have is arctg2(y;x) instead of arctg(x) , which returns values between 0-2pi instead of ...

Something like this ?

GLOBAL Pi AS DOUBLE, Pi_2 AS DOUBLE
....
Pi = 4*ATN(1): Pi_2 = Pi/2
....
FUNCTION ATN2 (YW AS DOUBLE, XW AS DOUBLE) AS DOUBLE
    DIM ZZZ AS DOUBLE
   SY&=SGN(YW): IF SY&=0 THEN SY&=1
   IF XW = 0 THEN ZZZ = Pi_2 * SY& ELSE ZZZ = ATN(YW / XW)
   IF XW < 0 THEN ZZZ = ZZZ + Pi * SY&
   ATN2 = ZZZ
END FUNCTION

[Erik Christensen]

Similar to the above I found this function in my previous 3D-Graphics Demonstration Program:

http://www.powerbasic.com/support/pb...ad.php?t=23341

FUNCTION CalculatePhi(EX AS SINGLE, EZ AS SINGLE) AS SINGLE
    ‘ EX and EZ are X and Z coordinates, respectively
    ' These corrections are needed to make Phi take a full
    ' circle i.e. 360 degrees.
    ' Without the corrections Phi will only vary 180 degrees
    ' (-90 to 90) corresponding to the range for arcus tangens (ATN).
    LOCAL Ph AS SINGLE
    IF ABS(EX) < EZ*1E-36! THEN EX = EZ*1E-36!
    Ph = ATN(EZ/EX)
    IF Ph < 0! THEN Ph=Ph+3.141593!
    IF EZ < 0! THEN Ph=Ph+3.141593!
    FUNCTION = Ph
END FUNCTION

Is this useful to you?

Best regards,

Erik

[Paul Dixon]

Frank,

BTW another feature which is interesting to have is arctg2(y;x) instead of arctg(x) , which returns values between 0-2pi instead of ...

Check out this: http://www.powerbasic.com/support/pb...ead.php?t=8959

Paul.

[William Burns]

Ah, he meant 'percentage' with '..%' ... I thought he meant a 16 bit integer variable by it ..

How funny. I on the other hand, thought he is talking about defining a constant that he can use for anything in his program that needs a color definition. Such as: %MYCOLOR = &H03A475F

[Frank Kestens]

color and Arctan2

Thanks for the useful conversion formulae ...
ArcTan2 works fine .

[Frank Kestens]

color conversion

You mean "%" as in a 16 bits integer ?
x, y, z are each 8 bits, that makes 24 bits ....

The PB RGB() function returns a 32 bits long ...

Kind regards

Ah ... I meant the colordefinition as in the HelpSection : DIALOG SET COLOR statement where predefined colors may be used as %BLACK ,
%WHITE ...
out of RGB(r%,g%,b%) values .

[Frank Kestens]

Color definition

Thanks for the codes here !
I was able to convert the color definition in RGB using :
color&=val("H0RRGGBB") , where RR...BB are the hexadecimal values.
This can be used fi. in the Graphic Ellipse commands ...