Stretch/Skew only one of several layers?

[Techineer]

Is there any way to stretch and skew only one layer out of several?

 

I repair electronic equipment.  Technical data is often very poor.  If I am VERY lucky the documentation includes an image showing the conductor traces on a circuit board and the component outlines showing their locations  and reference numbers with respect to the conductors.

 

If I am somewhat lucky, they at least show the component outlines and reference numbers (called a Silk Screen).  In this case, when I really need it, I make a graphics scan of the circuit board and overlay a scan of the silk screen in another layer.  Then the tricky part is getting them to align properly.

 

Sometimes the scan of the board does not come out perfectly rectangular.  Resizing and rotation can only go so far, and often I can align one edge of the board with the silk screen, but the other ends and corners no longer match up.

 

I need to be able to select that layer and drag the corner handles until the active layer lines up with the one above or below it.  The other corner handles should remain unmoved.  Even better would be to be able to select an area of the layer and manipulate the handles.

 

All the plugins I've seen reference to act on the entire image including all layers, and use a low-resolution box that doesn't give me the fine control I need.

 

I had hopes for the Layers/Rotate/Zoom control, but haven't been able to figure out how to make any of the controls do what I want.

 

Is there any hope?

 

Thanks!

[Ego Eram Reputo]

Yes there is hope!

Try Grid Warp

With the Gridwarp plugin your image is overlaid with a resizable grid. The grid intersections (nodes) are able to be dragged, moving the relevant area of the image. Try it. Its deceptively easy to use.

[skullbonz]

Grid warp might work if you could see the layer below it while you move the active layer but you can't so you will have no idea where you moved it to.  Have you tried the Move Selected Pixels tool? Activate the layer you want to move by clicking on it in the layer window, then use the Move Selected Pixels tool. You will have to click the image for the nubs to appear.

 

Edited March 21, 2015 by skullbonz

[Red ochre]

 

All the plugins I've seen reference to act on the entire image including all layers

? Effect plugins only work on one layer within the selection they are given.

The 'Oblique' plugin will skew symmetrically and other distort plugins such as 'TRsDistort this' or 'Quadrilateral reshape' may be useful too.

Click the link in Ego Eram Reputo's signature to find them in the plugin index.

 

SkullB - Gridwarp - 1. select and copy lower layer. 2. run Gridwarp on top layer - right click background and choose image from clipboard.

[skullbonz]

Ahh, never knew that, thanks Red.  

[MJW]

Not to plug my own plugin, but you might try my perpetually-beta (someday that will change)  Perspective Transformation plugin. Make the top layer semi-transparent, and drag the corners to line up with the corners of the lower layer. A perspective transformation may not be ideal, but for relatively small distortions, that probably won't matter too much.