Is there any way to project an isometric image to an orthographic view in Photoshop?

Question

Suppose I want the top view of this isometric graphic, how can I project an isometric image to an orthographic view in Photoshop?

Answer 1

If we assume that it's a perfect isometric projection, here is one out of several ways to revert to a top view:

• Select the layer with the image.
• Press Ctrl / Cmd + T to enter Free Transform.
• Make sure the Maintain aspect ratio chain is unticked.
• Enter 173.2051% (100 × √3) in the Set vertical scale field.
• Enter 45 in the Rotate field.
• Press Enter to Commit transform.

This gives you the following result:

The angles aren't exactly 90 degrees (I'm looking at the right and lower line with ocean which should be flat). This must be because the image isn't a perfect isometric projection to begin with.

Scaling to 176% gives a slightly better result:

You might be able to nudge your way to an even better result.

As you see, this only works for flat surfaces so the mountains aren't quite right. Nothing to do about that.

Answer 2

If the object is flat you need only to reverse the skew, scale and rotation. It's presented already by others.

If the object is not flat - like the mountains in your example, the task is impossible except by guessing the areas which are hidden in the isometric view. In practice they must be redrawn manually or you must somehow create a 3D model, guess right the texture in hidden areas and rotate the model or camera to get the top view.

In theory your isometric view could contain a known area from where also a proper 3D model or the wanted top view is available. Unfortunately I do not have a slightest idea where to start from to find them.

ADD: There's a plausible comment which says that the wanted view is not available in the source of this image. If that's true then you must paint what's behind the mountains. The visible side probably could be warped for something which resembles the top view but it generates a hole and you must fill that hole by knowing or guessing what the backside contains.

Here's my guess what's behind the south-east mountain. It's based on absolutely zero facts.