# why TramsformVecor(wolrd space to view space) get a wrong result in blueprint?

in post process material
some pixels’s z(mask b) values less than 0
in facts,in view space，i consider that all pixels’ z(mask b) values is positive

I’m guessing, from the preview, that 0,0 is screen center

so the bottom left quad is always blue.

i do it in RenderDoc like this

this output texture just like your pic
i think that is not view space texture
how could i solve this problem？

not only in blue print
The same whith this pic when I output it to the screen

What makes you think it’s not view space?

if it’s a view space,the pixels of bottom quadis that their mask B values must larger than 0
Mask b is Z distance in view space
the bottom left quad can not be blue

In the material preview, the bottom left is essentially at infinity.

In view space, Z is the distance from the viewing plane.

So Z is 1, the highest value it can take.

yes! In the material preview, the bottom left is essentially at infinity.
but in RenderDoc the postprocess material output that the reality rendering texture, the bottom left can not be infinity.

i am agree with you that In view space, Z is the distance from the viewing plane.
but, this means that the position of the camera is the origin
The z-axis of the camera is in the positive direction，so if there is any gameobject, the value of Z cannot be 0

i dont know wht does this mean “So Z is 1, the highest value it can take.”
i output the view space in the post-processing of unity. The effect is not the same as unreal

We are looking at raw node output as the material. It’s like UVs can only have that yellow/red 0-1 range. So, also the Z at max is blue.

Every point in the world can only be somewhere on the screen ( UV ), and have a Z depth ( blue ).

okay，i know your mean，It’s normal to display blue
However, why is there a black area in thebottom left quad of my picture?
My picture is the last color output to the screen

This black area is actually my scene terrain. Logically, its Z value（Mask B） should be greater than 0, and it will not display black

I don’t know about RenderDoc. I do know that the representation of coordinate systems differs between engines ( / software ). So you may well get things that don’t look the same.

Thank you, I now know that there may be differences between the material preview and the rendered picture.

What I want to say is that the display in the UE is also problematic.

In the display screen of the UE, the bottom left quad is still black.

Maybe this is related to the camera specified for display？

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Not sure, sorry

thank you for all you did
maybe i found the problem that the view port is look different from the mobile preview es3.1(PIE) in active play mode
but i dont know why…
the view space of the mobile preview es3.1(PIE) is correct…

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