Create dot matrix pattern mask?

[mysticfm]

I need to be able to create a mask or transparency that emulates a dot matrix or video pixel pattern for allowing through the content associated with it.  My image is 1600 x 800 pixels, and the size of the dot blocks I am trying to create is 7x7 pixels (yielding approximately 114 dots in one dimension times 228 dots in the other dimension, or about 26K dots).  And I can't figure out any way to create this mask with Affinity Photo short of attempting to manually draw in the 26K dots one by one ... which is never going to happen.  In other paint programs I've always been able to do this with a flood fill of a pattern, but the closest analogue I can find to this in Affinity Photo is to use the gradient tool with a bitmap ... and even this only seems to put ONE dot on the screen, no matter what I do.  There must be some way of automatically creating a tile pattern from an image (either as a mask, or even just as a bitmap layer with transparency that I could then attempt to convert into a mask), isn't there?  It seems like such a common task.

 

I have a project that has ground to a halt for the apparent lack of a way to do this, and am hoping there might be an answer that will get me going again.

[toltec]

To tile images with the Gradient tool. Draw a rectangle (you can't fill the whole page) choose Bitmap from Type, Extend from Wrap and you can tile any image. You will need to click Lock Aspect Ratio too.

 

The other option is to Power Duplicate. Create a grid of your dots 7x7. Press Ctrl + J to duplicate it, move it to the right, then press Ctrl + J until you get enough dots (er, you do the maths ). Select them all, Ctrl + J  to duplicate, and then move them all down, then Ctrl + J again until you have enough dots vertically.

 

Only takes a few minutes.

 

[JimmyJack]

It might also suit your needs to use the Halftone filter (under Filters > Colors ) on a filled shape (or rasterized fill layer).

Rasterize that to mask.

[mysticfm]

22 minutes ago, JimmyJack said:

It might also suit your needs to use the Halftone filter (under Filters > Colors ) on a filled shape (or rasterized fill layer).

Rasterize that to mask.

 

An interesting idea.  However, that's more of a print look, whereas I need something more like the equally sized dots of a video display.

 

1 hour ago, toltec said:

To tile images with the Gradient tool. Draw a rectangle (you can't fill the whole page) choose Bitmap from Type, Extend from Wrap and you can tile any image. You will need to click Lock Aspect Ratio too.

 

The other option is to Power Duplicate. Create a grid of your dots 7x7. Press Ctrl + J to duplicate it, move it to the right, then press Ctrl + J until you get enough dots (er, you do the maths ). Select them all, Ctrl + J  to duplicate, and then move them all down, then Ctrl + J again until you have enough dots vertically.

 

Only takes a few minutes.

 

 

I don't know why the Gradient tool doesn't work that way for me ... I must be doing something wrong.  I never get any sort of tiling of the image.  Same thing goes for when I set as Mask to use a bitmap ... only get one instance of the source image, with no tiling.

 

I did find a solution early this morning, though.  I got the idea from the video below, although I didn't follow it exactly.  I created a white dot on a black (not transparent) background, and saved that as a PNG.  I then created an image of the same size as my target image, and did the Fill Layer method from the latter part of this video to create the pattern that I wanted.  I then saved THAT file as a PNG.  Finally, on the target image I created a new Mask layer, set it to Bitmap and loaded the latter, larger PNG.  (In theory I think I should have been able to skip the middle step and create the mask by tiling the first image, but as I said above, that doesn't work for me for some reason ... I can only get the tiling with the Bitmap mode of the Fill Layer.)  

 

I've also attached the result of this, so you can get an idea of what I was going for.