is the solid brush opaque?
e.g. I have code like this
pw =24
dim solidbrush as CGpSolidBrush = GDIP_ARGB(0, 0, 0, 255)
DIM blackPen AS CGpPen = CGpPen(GDIP_ARGB(20, 0, 0, 0), pw)
blackpen.setlinecap(linecapround,linecapround,linecapround)
blackpen.setbrush(@solidbrush)
then in the line generating loop, I have
'gradually darken lines from centre
blackpen.setcolor(GDIP_ARGB(20+j, 0, 0, 0))
graphics.DrawLine(@blackPen, x,y,x1,y1)
where the ends of the lines overlap it seems the colour is darker. (more like painting with a transparent paint (e.g. watercolour) as opposed to an opaque colour (e.g. oils))
I guess there may be another value to set, or perhaps the order of the various pen settings/brush settings need changing. (the circular dark gey blobs, and the outlining should not be there if opaque colour.)
To make it opaque, you must set the alpha value to 255.
See: https://docs.microsoft.com/en-us/windows/win32/gdiplus/-gdiplus-drawing-with-opaque-and-semitransparent-brushes-use
Thanks, Jose, I should have known that... well, i did a few years back.
changing pen colour to blackpen.setcolor(GDIP_ARGB(255,20+j,20+j,20+j)) does what I was looking for.