OpenEuphoria

Re: Graphics Doubts

• Posted by Lucius L Hilley III <luciuslhilleyiii at JUNO.COM> Jul 11, 1997
• 910 views

On Fri, 11 Jul 1997 20:09:19 +0000 Ralf Nieuwenhuijsen writes:
>>  Hi to all.
>>  I agree with Eric Dobbertin, when we read and display a BMP file in
>the
>> screen, a rectangle wich color variate with the palette used appear
>around
>> the corners of screen. I'd like to know if anyone have a solution to
>> this...
>        Well, some color value of the palette is used, i think it is
>either
>0 or 255, try and find out...

palette color 16 is the screen border.
quick and lousy solution is.
pal_bmp = read_bitmap("someimge.bmp")
pal = pal_bmp[1]
bmp = pal_bmp[2]
pal[16 + 1] = {0, 0, 0}

>
>>  Another thing is: why I can't turn the background color when a
>bitmap is
>> being displayed in screen?
>        There is NO such thing as background color in Graphics mode,
>everything is foreground color. If you set the background color it
>only changes the palette (the visible color) of each pixel drawn with
>color 0. BitMaps dont' have background colors too. You are asking the
>wrong question...
>        Why did you assume there is a background color in Graphics
>Mode,
>Euphoria isn't a human robot that can deside what is background and
>what not when you're plotting pixels.. with text it can.. the
>character itself is foreground and everything else is background..but
>NOT with background, no matter what some1 tells you, there is no such
>thing as a REAL background color in graphics mode, there are only
>some routines that assume that color 0 is the background color.
>        But you can check what the palette value is of your image
>background
>(a value between 0 and 255) and then set the color it shoudl be (
>color is a combination of RED BLUE and Yellow)

Ralf, it is not (RED, BLUE and Yellow).
Monitors are sometimes called RGB monitors BEACUSE they use
"R"ed, "G"reen, and "B"lue
The values are {Red, Green, Blue}
The values can go from 0 to 64 in Euphoria.
In Windows and other programs they can go from
0 to 255

Examples:
Black = {0, 0, 0}
Red = {64, 0, 0}
Green = {0, 64, 0}
Blue = {0, 0, 64}
White = {64, 64, 64}

>>  And finally, how much colors Euphoria can suport? (please, don't
>send me
>> projections and proportions, I really want to know in numbers, like
>16
>> colors, 256 colors, 16800000 colors <-- WOW!).
>>  Thanks to all..

64 x 64 x 64 = 262,144
So "262,144" colors are available.
Only 256 can be used and showed at any given time
Only 256 can be stored on the palette.

Windows would support
256 x 256 x 256 = 16,777,216

>        Read Packard's tutorial, but the maximum colors support in
>Euphoria
>is 256 colors, but you have to be in a videomode of that number of
>colors (like Mode 19)
>

--Lucius Lamar Hilley III
--  E-mail at luciuslhilleyiii at juno.com
--  I support transferring of files less than 60K.
--  I can Decode both UU and Base64 format.