Keywords to access the screen position in Surface shader

Unity Engine
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1

Are there any? I want to use screen space UV mapping in one special effect

2

Look at the list at the bottom of the page.

Look for “Detail Texture in Screen Space”

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3

Thanks, you are always saving me! One thing I dont understand, why in this example screenpos.xy is divided by screenpos.w? To bind the scale of a texture to relative size of the object?

4

Nope. Completely unrelated to the object size. It’s because the values are homogeneous coordinates (aka projection space coordinates). The xyz values are multiplied by w during interpolation between vertices which ensures they interpolate linearly in screen space. The w component for a perspective camera is the view depth. So you have to divide by w in the fragment shader to get them back into 0.0 to 1.0 range.

Look up that term homogeneous coordinates if you want to understand it better.

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5

Okay, will check. Should work without me knowing that, but I had to make sure