Extreme newbie question - cannot create any shapes; cannot find preview

[keiichi_m]

Hi,

Apologies for this very stupid question. I downloaded QCAD 3.22.1 and tried to use it like a drawing or CAD program. I could not create any shapes.

So I got the manual and followed carefully the "Hands-on: Drawing a Rectangle" instructions which are on p 22 of the manual. Step 8 works, where I click somewhere to establish the first corner of the rectangle.

Then, the manual says, "If you move the mouse cursor around in the drawing area, you will see that QCAD draws a rectangle from the chosen position to the grid point that is closest to the mouse cursor as shown below:"

This preview does not happen on my Win 7, Lenovo T440 laptop. If I keep clicking I see the command window switching between "first corner" and "second corner". But nothing is ever drawn. I tried to draw lines and other shapes, and none work. The preview never shows up.

Maybe the canvas is white and the preview is white? I do notice that the color of the canvas flashes between white and grey as I move the mouse around, which Idon't understand.

I must be missing something tremendously simple here. Can you tell me what it is?

Thanks,
K

[andrew]

Make sure to check the option:
Edit > Application Preferences > Graphics View > Appearance > Prevent white on white / black on black display

This way you never end up drawing in white on white or black on black.

[keiichi_m]

Thank you for your reply. I looked at the Application Preferences, and the box, "Prevent white on white / black on black display" was already checked.

[andrew]

OK. Do you get any warnings when doing the second click? Perhaps your layer is locked? If you cannot solve the problem, please save your file and attach it.

[andrew]

Might also be worth trying to switch your background to black:
Edit > Application Preferences > Graphics View > Colors > Background > black

[keiichi_m]

No, there are no warnings when I do the second click. The command windows goes between "first corner" and "second corner."

I looked at the settings for Background an to my surprise, that was already set to black. However, the background is white, with grid points and lines in light grey.

[andrew]

Not sure what's going on there to be honest. I'd suggest to try resetting your QCAD configuration:
https://qcad.org/en/tutorial-resetting- ... figuration

[keiichi_m]

Thanks for your patience... I deleted the QCAD.ini and QCAD_old.ini files from the AppData directory.

Started QCAD again, and this time the background is black as expected. I follow the instructions to make a rectangle. As soon as I make the first corner click, the background goes white. And the elusive preview of the rectangle is not appearing. I tried clicking, dragging, etc. This makes the background shift between gray and white. It never seems to go back to black after the first mouse click.

[andrew]

OK. Please do save and attach the file, thanks.

It sounds like you must have either zoomed in a lot or chosen a tiny drawing unit, so that the line weight is now so huge that a single line fills out the entire visible drawing area.

[Husky]

That sounds weird ....

Just to get the common suspects out of the way ...

1. the QCAD installation isn't mixed with multiple attempts to install the software in one and the same directory, correct?
2. your graphic card is proper working with all other software on your computer - especially with high demand software like graphic design software, correct?
3. how much RAM is installed on your computer?
4. whats about the hard-drive - enough remaining space space for application like QCAD?

[andrew]

Husky: I think it's a simple matter of zooming in alot. Once your screen measures only micrometers across, you get that behaviour when drawing lines with a width of let's say 0.25mm. A line then fills out the whole screen.

[Husky]

Makes sense - thanks for the clarification.

[keiichi_m]

Thank you so much for the suggestion about units. I am doing IC layout so naturally I set the unit to be "micron." I did not realize that would cause the preview to disappear and the program to not function in a way I expected.

I just changed the unit to "millimeter" and the preview appears. So I just have to remember that everything is scaled by 1000x. This won't be hard.

I will get on with trying out other aspects of the program.

Thanks again for the key piece of information!