Perpendicular Line

Hello,

I have drawn a line on the VB Form as follows:

VB Code:

Line (OriginX, OriginY)-(OriginX + WeightX, OriginY - WeightY)

Where OriginX and OriginY are both zero and WeightX and WeightY are any two values. Now I want to draw a line which is perpendicular to this line on the origin point. For clear viewing, I have shifted the axis to some other point.

So, my question is how can I find two points to construct a line which is perpendicular to another line whose one point is origin and other point is also known.

Any help will be appreciated.

Thanks.

two lines are perpendicular if they are negative inverses.

so...after checking for horizontal/vertical lines {You can't invert zero, or infinity, in VB ;) }, do some algebra:

Slope = (-WeightY)/WeightX
NewSlope = -1 / Slope (BTW, this is just WeightX/WeightY)

now draw a line (OriginX, OriginY) - (OriginX + ScaleFactor, OriginY + ScaleFactor * NewSlope)

where Scale Factor depends on how big you want the line, and in which direction.

No reason to be complexe at all, SQL.

(originx,originy) to (originx + weight y, originy - weight x)

:wave: