PC Graphics

[JongseokOh]

Hello everybody,

I can't partially select an entity drawn with "GL_LINE_STRIP" using "OpenGL" on "RX 550/570/580".

This figure is a line (black line) drawn by connecting several points with "GL_LINE_STRIP". And the highlighted line is the selected part among the areas drawn in the same way.

The basic code is as follows.

-------------------------------------------------

glLoadName(unsigned long);

glBegin(GL_LINE_STRIP);

for (i = 1; i < pointArray.size(); ++i)

{

glVertex2dv(pointArray[i].x);

}

glEnd();

---------------------------------------------------

I don't know the cause of the problem, but I've noticed strange phenomena.

1. The same problem occurs if you paste and draw with "GL_LINES" instead of "GL_LINE_STRIP".
2. There were cases where the areas divided by begin/end affected each other.
   1. The figure below is a form of drawing 4 lines in half in the above method. But if you look at the black lines, it is observed that entities that ended with end() are connected.
      1. 
3. If I draw GL_LINES like a dotted line, I can select it.
   1. As a shortcut, it is possible to select a perfect line by drawing GL_LINES with intersecting dotted lines.
   2. But this is a shortcut, but not the right way

Of course, I have the latest drivers. Do you know anything about this problem?

I searched in sites and found "Adjust the width of the line" and "Move it finely", but all of them were to no avail.

Thank you.