Difficulty using Flip Horizontal

[Charles Jenkins]

I'm writing to share some tips, but I also hope Affinity developers will see these and make the Arrange tools easier to use in future versions.

I'm working on texture images for 3D models which need to be symmetrical from left to right. Conceptually for me, the easiest thing to do is paint on the left side, duplicate the layer, flip the copy, and mask if necessary. But I've found it exceptionally difficult to get expected behavior from Affinity Photo's Arrange menu items.

Keep in mind that all these tips are in the context of using Flip transforms to end up with artwork that is mirrored left-to-right or top-to-bottom.

Tip #1: If the layer you want to mirror has a mask, make sure there are visible pixels somewhere at the extreme edges.

Photo apparently does not use the current selection as a guide to how you want to flip stuff. So if the layer you need to flip was created by pasting, it might flip according to bounds smaller than your full image width, even if you hit Ctrl-A to select the full image bounds before flipping. As a result, even if the visible pixels mostly fill the layer, the flipped portion can end up the the wrong place. To be sure my flipping will result in a mirror image, I make sure to paint a few visible pixels along the left and right edges when flipping horizontally, or along the top and bottom edges when flipping vertically. Basically I use pixel painting to make sure the layer I'm flipping extends across exactly the full width or height of the image before I flip it.

To be fair, Photo's behavior in this regard is not a bug. If you've pasted in something small on a collage and need it to face the other way, you don't want it to jump from one side of the screen to the other when flipped.

Tip #2: Temporarily set the layer to full opacity and Normal mode before flipping, if applicable.

Today I had a layer with a mask set to Color Burn mode at 10% opacity, and flipping horizontally simply erased the layer's content. I tried several times but always ended up with a blank layer. I wondered if opacity or mode was somehow confusing the program, so I set the layer to Normal mode at 100% opacity, and then flipping worked.

Tip #3: If the Arrange menu items are grayed out, lasso- or box-select something to copy and (temporarily) paste.

I started a new document from an image I wanted to mirror. After duplicating the Background layer, I found the Arrange menu's transform items all grayed out. In an attempt to enable them, I tried all these things in turn:

• Made sure the unlocked duplicated layer was selected
• Hit Ctrl-A to select the full image size
• Saved and quit and reopened the program
• Renamed the duplicate layer in case the program prevents you from transforming based on the name "Background"
• Added a new, empty pixel layer
• Quit the program again and updated to version 2.2.0 before retrying

Nothing worked. Then I used the lasso to copy and paste a small portion of the duplicated layer, and the Arrange menu items came alive. After that I was able to delete the temporarily pasted layer and then flip the duplicated layer.

 

[fde101]

On 9/28/2023 at 4:22 PM, Charles Jenkins said:

Tip #2: Temporarily set the layer to full opacity and Normal mode before flipping, if applicable.

Today I had a layer with a mask set to Color Burn mode at 10% opacity, and flipping horizontally simply erased the layer's content. I tried several times but always ended up with a blank layer. I wondered if opacity or mode was somehow confusing the program, so I set the layer to Normal mode at 100% opacity, and then flipping worked.

Tip #3: If the Arrange menu items are grayed out, lasso- or box-select something to copy and (temporarily) paste.

I started a new document from an image I wanted to mirror. After duplicating the Background layer, I found the Arrange menu's transform items all grayed out. In an attempt to enable them, I tried all these things in turn:

• Made sure the unlocked duplicated layer was selected
• Hit Ctrl-A to select the full image size
• Saved and quit and reopened the program
• Renamed the duplicate layer in case the program prevents you from transforming based on the name "Background"
• Added a new, empty pixel layer
• Quit the program again and updated to version 2.2.0 before retrying

Nothing worked. Then I used the lasso to copy and paste a small portion of the duplicated layer, and the Arrange menu items came alive. After that I was able to delete the temporarily pasted layer and then flip the duplicated layer.

These two sound like they should be in the bug report section.