Mega Code Archive
Calculate a TColor between two other TColors
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Title: Calculate a TColor between two other TColors
Question: I needed a function that calculates a TColor-Value between two others from an Extended. This Extended should be limited from two other Extended
Variables.
Answer:
I needed a function that calculates a TColor-Value between two others
from an Extended. This Extended should be limited from two other Extended
Variables. All Values of "Pointvalue" less then "von" will return "Startcolor" and all Pointvalues greater than "Bis" gives EndColor back. Ist written with some Inline- Assemblercode. I think maybee its could be usefull for somebody else.
Have Fun with it.
function GetColorBetween(StartColor, EndColor: TColor; Pointvalue, Von, Bis : Extended): TColor;
var F: Extended; r1, r2, r3, g1, g2, g3, b1, b2, b3: Byte;
function CalcColorBytes(fb1, fb2: Byte): Byte;
begin
result := fb1;
if fb1 if fb1 fb2 then Result := FB1 - Trunc(F * (fb1 - fb2));
end;
begin
if Pointvalue result := StartColor;
exit;
end;
if Pointvalue = Bis then begin
result := EndColor;
exit;
end;
F := (Pointvalue - von) / (Bis - Von);
asm
mov EAX, Startcolor
cmp EAX, EndColor
je @@exit
mov r1, AL
shr EAX,8
mov g1, AL
shr Eax,8
mov b1, AL
mov Eax, Endcolor
mov r2, AL
shr EAX,8
mov g2, AL
shr EAX,8
mov b2, AL
push ebp
mov al, r1
mov dl, r2
call CalcColorBytes
pop ecx
push ebp
Mov r3, al
mov dL, g2
mov al, g1
call CalcColorBytes
pop ecx
push ebp
mov g3, Al
mov dL, B2
mov Al, B1
call CalcColorBytes
pop ecx
mov b3, al
XOR EAX,EAX
mov AL, B3
SHL EAX,8
mov AL, G3
SHL EAX,8
mov AL, R3
@@Exit:
mov @result, eax
end;
end;
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