Search a position color an a 45° line angle

[MOHagen]

Hello, 

I would want to know if there is a easy / fast solution to check if a color exist on a line.
I got two point, P1 (x:780, y:1280) and P2 (x: 1065, y:203) and I'm looking for the Blue color position (see below)

On the purple line From P1 to P2 I want to get the position of the first occurrence of blue color (P3), some kind of ray casting.

Is there a way to do it ?
Thank you.

[Jos]

3 minutes ago, MOHagen said:

some kind of ray casting.

which means what exactly?   

[MOHagen]

Sorry "Ray tracing"

 

[MOHagen]

In fact it's pretty similar "casting or tracing"

Like here for each line to get the first pos of the "green" match

[Zedna]

Generally:

Go in For/Next cycle from x1 to x2 pixel by pixel, calculate apropriate Y for that each X (some sin,cos math?) and use PixelGetColor(X,Y).

 

EDIT:

If it's 45° then Y calculation will be very simple: Y=Y1+(X-X1)

Edited September 25, 2020 by Zedna

[MOHagen]

Yes it is what I thought to just basically iterate on each point of the line but I wasn't sure it was the most efficient way (I'm pretty beginner with it then I'm not aware of all functionalities included