HSV toolkit v1.00
A toolkit to convert from the RGB into the HSV colour
system and vice versa. Also has helper functions for
creating an interactive HSV colour picker.
Free for non-commercial use, I'd just like a copy of
the result and please give some credit.
©2006 Marcel Kilgus
HSV_GETH
HSV_GETS
HSV_GETV
Syntax: h = HSV_GETH(r, g, b)
s = HSV_GETS(r, g, b)
v = HSV_GETV(r, g, b)
Returns the respective HSV component of the given RGB
colour value. The RGB variables may range from 0 to
255. The resulting h, s, v variables also range from
0 to 255. h might be -1 if it is undefined.
HSV_GETR
HSV_GETG
HSV_GETB
Syntax: r = HSV_GETR(h, s, v)
g = HSV_GETG(h, s, v)
b = HSV_GETB(h, s, v)
Returns the respective RGB component of the given HSV
colour value. All variables have the range from 0 to
255.
HSV_GETRGB
Syntax: rgb = HSV_GETRGB(h, s, v)
Returns the complete 24-bit RGB colour for the given
HSV components.
HSV_HSSPR
Syntax: adr = HSV_HSSPR
This generates and returns the address of a GD2 sprite
that shows all possible hue and saturation colours.
The sprite is 128x128 pixels big, horizontal is the
hue axis, vertical is the saturation axis. The value
component is fixed to 255.
The memory returned by this function can be freed by
the HSV_RCHP command after use.
HSV_VSPR
Syntax: adr = HSV_VSPR(x, h, s)
This generates and returns the address of a GD2 sprite
that shows all possible value colours for a given pair
of hue and saturation components. The sprite is 10x128
pixels big. If x is 0 on entry, new memory is allocated
to contain the sprite. If x is not 0, then the given
address will be used and returned.
The memory returned by this function can be freed by
the HSV_RCHP command after use.
Example:
adr = 0
REPeat
adr = HSV_VSPR(adr, H%, S%)
SPRW 0, 0, adr
[...]
END REPeat
HSV_RCHP adr
HSV_RCHP
Synta: HSV_RCHP adr
Can be used to free the memory that was implicitely
allocated by HSV_HSSPR and HSV_VSPR.
Examples
hsvdemo_bas and hsvdemo2_bas are 2 simple SBasic programs
that show the use of all commands. Both need the QPtr
toolkit to run, but could easily be ported to other
PE toolkits within minutes.
In hsvdemo_bas you can use the cursor keys to navigate
the H/S sprite and thus change the colour. The value
component can be changed by the +/- keys.
In hsvdemo2_bas a click with the mouse within the H/S
sprite or the value ramp will change the colour.
Back to top of page
|
