Reverse perspective rendering

brothermechanic · March 16, 2020, 4:50pm

Hello
wanted to ask for any advice
how do i make a reverse perspective effect in a blender
like this

I think it somehow can be possibly implemented through a osl shader with a projection matrix

anon20675008 · May 24, 2020, 3:23pm

Hello! Here are the results of my experiments with a reverse perspective camera. This is a patch for code. It is still very raw code, but managed to make a preview in the 3DView window and visualization for EEVEE. For a reverse perspective camera, the settings are the same as for a simple camera, but the “Reverse” flag has been added.

samdraws · May 29, 2020, 11:06am

Hi @anon20675008 — I got here via googling ‘reverse perspective’ and this seems to be the first thing I’ve seen that actually does it.

I can’t quite figure out your reply though — did you write some code to implement the ‘reverse perspective’ checkbox? If you could shed some light on exactly how you got there that’d be amazing!

anon20675008 · May 30, 2020, 6:30am

There is program code in my builds.
The picture shows the interfaces of my assembly.
I plan to publish the source code and build it under Linux soon.
I now need models to test before publishing.
Now my builds doing visualization in EEVEE, but there are some developments for Cycles too.
Yours models can be sent to sungreen@ya.ru to show that the “reverse perspective” effect works quite well.

moony · June 6, 2020, 12:17pm

I think the real world example of this is the hypercentric lens.

samdraws · June 6, 2020, 12:39pm

Sorry @anon20675008 — I have to edit this post because I can’t reply more than 3 times!

I don’t any experience compiling blender with patches — so I’m happy to wait a bit longer for the Cycles version. How would I install the code for eevee?

anon20675008 · June 6, 2020, 5:13pm

I can publish the code for eevee now, but I could not make the partable blender build static_libs so soon. Can you compile blender with the patch yourself?

anon20675008 · June 8, 2020, 6:22pm

Hi!
Link to demo builds for linux https://drive.google.com/file/d/1LA2kHUWxUZssDQll_43k0ZUs9oCcAJly/view?usp=sharing
Demo video https://youtu.be/6ri9og_RtbU
Examples:

dace

dace_demo960×540 121 KB
dice_reverce.blend (716.7 KB) ![teapot_demo|690x420]
teapot

teapot_demo1680×1024 147 KB
teapot_reverse.blend (1.1 MB)

samdraws · June 8, 2020, 8:33pm

Hi @anon20675008 — that’s amazing! Thanks so much for sharing it. Do you have any advice on building / combining in a way that would work for mac? I appreciate how much you’ve done already so no worries if not!

Also I think I can only reply three times to this post so I may not be able to reply after this!