Welcome, Guest.
Username: Password: Remember me

TOPIC: Quick noob question

Quick noob question 1 year 1 month ago #1

If I am running a shader pass which renders to a 1x1 pixel texture, that shader pass only runs once per frame, right? (Or 8 times to a 4x2 pixel texture, etc.)
The administrator has disabled public write access.

Quick noob question 1 year 1 month ago #2

  • Marty McFly
  • Marty McFly's Avatar
  • Offline
  • We've tried nothing and we're all out of ideas!
Correct.
But mostly some complex math that has small output data has huge compilation time, so this is more a culprit than execution time.
The administrator has disabled public write access.
The following user(s) said Thank You: Citizenkane

Quick noob question 1 year 1 month ago #3

When you mean compilation time, do you mean like when ReShade starts up, processing effects? In terms of execution time, I can definitely see how crazy math on one pixel might take a lot longer than simple operations on many pixels - especially because of how the GPU parallelizes everything.

Otherwise, that makes perfect sense, thanks!
Last Edit: 1 year 1 month ago by Citizenkane.
The administrator has disabled public write access.

Quick noob question 1 year 1 month ago #4

  • Marty McFly
  • Marty McFly's Avatar
  • Offline
  • We've tried nothing and we're all out of ideas!
Yes, at startup. A shader with an unrolled loop takes some time to compile, no matter the amount of pixels it runs on. Calculating avg color of screen by averaging as many pixels as possible is an example for heavy compilation time, even with a 1x1 output so performance hit is almost non existant.
Last Edit: 1 year 1 month ago by Marty McFly.
The administrator has disabled public write access.
The following user(s) said Thank You: Citizenkane

Quick noob question 1 year 1 month ago #5

Interesting, very good to know!

Cheers :)
Last Edit: 1 year 1 month ago by Citizenkane.
The administrator has disabled public write access.