Gradiant from an array of value

[FabDev 8]

Hello,

 

I'am looking since a few time, without any success, a function which return me a gradient (Tcolor) from an array of double (or integer) value.

 

For example :
 

Const

 REVENUE_ARRAY: array [1 .. 5] of integer= (10,15,30,45,60);

 

Result with a gradient from Yellow to red :

10 => Yellow

...

30 => Orange

...

60 => Red

 

My purpose is to fill a MAP ShapeFile items (Devexpress MAP) with a gradient which correspond to a Revenue array ( REVENUE_ARRAY)

[corneliusdavid 214]

So since you can't find one, just write your own. It shouldn't be terribly difficult. You could probably even calculate the RGB value based on the number given.

[Anders Melander 1782]

https://docs.microsoft.com/en-us/windows/win32/api/wingdi/nf-wingdi-gradientfill

 

...or since you're using DevExpress anyway, use one of their gradient functions.

[hsauro 40]

FMX has a TGradient non-visual class, I’ve used it in the past. Might be worth looking at, though I notice your referring to TColor  rather than TAlphaColor so it might not be applicable.

[FabDev 8]

Yes it's not so complicated. But find an already done (and tested) function is often less time lost.

 

Some component has this kind of function but not always easy to find/extract.

 

Finally a colleague, which has code a lot on assembler on Atari 68000/68030 (Doom version) , took a nasty pleasure to code this function with a lot of SHR and boolean operator 😉. So it will not take a lot of time to execute even on  CPU with 8 Mhz clock speed 😉

 

 

 

Edited May 24, 2022 by FabDev