Access to last frame's matricies

[CptPotato]

I tried playing with temporal filtering in this app but quickly ran into the problem that there's no way to get data (variables) from the previous frame. It would be neat if there was a way to access the last frame's matricies, which are needed in temporal reprojection algorithms.

To select them they could simply be added to the list in the variables window:

On a different note, inverse matricies are also often used in shaders. It would be nice if they were available aswell, but it's not a big issue since they can be calculated in the shader.

[dfranx]

Thanks for the suggestion! I will implement this tomorrow (and the binary will probably come out on sunday/monday) as unfortunately I don't have time to program today.

I was thinking maybe adding some kind of checkbox that takes values from the previous frame when checked would be a good way to solve this (instead of adding bunch of "LastFrame*" variables + this way you can get every existing 'system' variable's value from the last frame).

And I would probably do the same for the inverse matrices - a checkbox that inverses the matrices when checked.

This would be quite easy to implement. Opinions?

[CptPotato]

Sounds great to me. No reason to rush, though 😄

[dfranx]

Hey! I have just published the binary with all of the suggestions you made. Could you please test them so that I can close the issues? I would test them myself but I currently don't know how to utilize those features properly heh. Also could you post some screenshots in the "Post screenshots here" issue? I'd love to see some cool shaders built with SHADERed! :D

[dfranx]

Also, I forgot to make the checkboxes for the flags visible but you can still use them. The UI for flags should probably change completely in the future - although I don't know what would make it look better and more simple

[CptPotato]

So I tried it and the view-projection matrix works fine with this feature but geometry transform somehow doesn't.

Edit: weird, on a clean project it works.
Edit2: looks like it has something to do with using these last frame properties and having multiple objects in the scene.

[dfranx]

Oh I didn't think about that. What's causing this is that I actually have only one matrix which is used to store all the geometry transform. So before each rendered item I update the matrix to store that item's transform... and then after I copy the value, I actually copy only the last rendered item's transform matrix. There are also probably other values that wouldn't work (the only I can think of right now is the viewport size when each shader pass is rendering to different sized viewport). I'll have to rework that..

[dfranx]

Fixed!
Also, I disabled the last frame flag for viewport size - don't see the practical use for it and don't want to change half of the code currently. I will leave that disabled until I start working on a support for multiple cameras.