[solved] Opaque Fill

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dickbob
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[solved] Opaque Fill

Post by dickbob » Thu May 20, 2021 9:54 am

I have an architectural drawing that has a basin on the wall with boxing below it along the wall/floor junction.

Rather than snip out the portion of the boxing that would be hidden by the basin above, can I give the basin outline an opaque fill so that the boxing is automatically hidden if I slide the basin along the wall or move it to another wall with boxing beneath?
Last edited by dickbob on Tue May 25, 2021 8:39 am, edited 1 time in total.

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andrew
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Re: Opaque Fill

Post by andrew » Thu May 20, 2021 9:56 am

With the hatch tool, you can also create solid fills:
https://qcad.org/doc/qcad/latest/refere ... mSelection

dickbob
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Re: Opaque Fill

Post by dickbob » Thu May 20, 2021 11:37 am

Sorry, but I can't seem to get this to work for me as I want.

I'm made sure the shape is closed, selected it, then Draw > Hatch > Hatch from Selection (HA) then selected Solid Fill which then fills the shape with the Layer colour. I then select the hatch block and set the colour to White with the Property Editor.

When editing the drawing all I see is the white shape, which is not ideal but when printing it prints as a solid black shape.

Am I missing something or is there no solution to my problem?

CVH
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Re: Opaque Fill

Post by CVH » Thu May 20, 2021 11:55 am

Hi,
Change the Alpha value of the Hatch entity in the Property Editor.

Regards,
CVH
Attachments
HatchAlpha.png
HatchAlpha.png (9.84 KiB) Viewed 6387 times

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andrew
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Re: Opaque Fill

Post by andrew » Thu May 20, 2021 2:42 pm

To allow white on white printing, please change your preferences as described here:
https://qcad.org/rsforum/viewtopic.php?p=24336#p24332

dickbob
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Re: Opaque Fill

Post by dickbob » Thu May 20, 2021 5:42 pm

Thank you CVH, the alpha value is already 255.

Thank you Andrew, I did manage to get that white on white printing working on a new, fresh, simple, drawing from first principles. I just can't get it to work with my drawing. I guess I must have something screwed up in the layering in my ignorance of how to structure a QCAD drawing -- frustrating!

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petevick
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Re: Opaque Fill

Post by petevick » Thu May 20, 2021 6:56 pm

dickbob wrote:
Thu May 20, 2021 5:42 pm
Thank you CVH, the alpha value is already 255.
What CVH meant is that you reduce the alpha value to increase the transparency, or opacity, of the color
Pete Vickerstaff
Linux Mint 21.2 Cinnamon, Qcad Pro 3.29.6

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andrew
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Re: Opaque Fill

Post by andrew » Thu May 20, 2021 7:15 pm

dickbob wrote:
Thu May 20, 2021 5:42 pm
I just can't get it to work with my drawing.
Perhaps, you can attach your drawing, so we can help efficiently, thanks.

dickbob
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Re: Opaque Fill

Post by dickbob » Fri May 21, 2021 8:27 am

Thanks Pete, I did understand what CVH meant but I did an experiment just to confirm that 255 = totally opaque and 0 = totally transparent so 255 is what I need and what the hatch block was originally set to when I created it.

I think, Andrew, I've managed to workout the settings I need to get it to work as I want. Drawing Preferences > Printing > Colors > Full Color or Grayscale with the Background color set to White. Setting the Color Mode to Black / white prints my filled blocks as black.

It prints ok but I've now got all these white blocks on the drawing as I'm working on the.

Thank you for your offer to review my drawing (please don't laugh), I will take you up on that -- please see attached.
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ground floor v4.dwg
(38.89 KiB) Downloaded 287 times

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Husky
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Re: Opaque Fill

Post by Husky » Fri May 21, 2021 8:07 pm

@ dickbob,

just for clarification. A proper CAD drawing would contain the hidden parts as a dashed line like this example:

Husky-2021.05.21-01.png
Husky-2021.05.21-01.png (25.12 KiB) Viewed 6280 times
What you are trying to do is to use features from a Graphical software in a CAD software - that will only work to a certain point. I don't think it will ever work with the chosen color black or white just because the Model_Space has a black background and the Print Preview has a white background. What ever the QCAD preferences are to deal with black on black or white on white has to fail in one or another way. That's fact!
Howsoever - to come close to your goal you could use colors for the hatch like "Light gray" or something similar and the result could be something like this:

in Model_Space ...

Husky-2021.05.21-02.png
Husky-2021.05.21-02.png (23.84 KiB) Viewed 6280 times
... and in Print Priview

Husky-2021.05.21-03.png
Husky-2021.05.21-03.png (24.42 KiB) Viewed 6280 times

If the hatch is still hiding lines you can play with "Bring to Front" or "Send to Back". BTW: I kept Alpha to 255 ... :wink:
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dickbob
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Re: Opaque Fill

Post by dickbob » Tue May 25, 2021 8:35 am

Thanks for your insight Husky.

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