Does interlacing cut down on GPU load?

[rabidz7]

Will running an interlaced resolution lower the amount of load on the GPU since it only has to draw half the screen each refresh. And will my two 980s get 120FPS at 2560x1920i?

 

[Kor]

You won't receive any performance boost at the simulation level, the full scene still needs to be drawn.

 

[serpretetsky]

As far as I know, LCDs do not natively support proper interlacing. In other words, they always refresh progressively, and any interlaced image that needs to be displayed on an LCD must first be flattened to a single frame to be drawn progressively.

However, i get my information from the popular knowledge of the internet. Let me know if you find out anything contrary to this, because this really interests me.

wiki from MythTV has this little interesting nugget

Double Framerate
The best deinterlacers will double the frame rate (typically 29.97fps in the USA) to 59.94fps, which is the rate at which the fields (half-frames) of interlaced video occur. For each field, they will build a whole frame. This requires that your display be able to operate at this doubled frame rate. Surprisingly some displays are just a hair below that, in which case MythTV will switch to your "fallback" deinterlacer, as set on your configuration screen. Doubling the frame rate requires a lot more resources. Some video comes at 25fps, which doubles to 50fps and should not have a problem with the monitor refresh rate. You may also encounter problems with loss of deinterlacing if doing time stretch.

https://www.mythtv.org/wiki/Deinterlacing

I never really thought about that doing that. So maybe some LCD's can increase your fps with interlacing and still redraw everything progressively?

Either way, how would you even go about setting interlacing on the pc? I mean... theres no options in resolution to set interlaced is there?

 

[rabidz7]

As far as I know, LCDs do not natively support proper interlacing. In other words, they always refresh progressively, and any interlaced image that needs to be displayed on an LCD must first be flattened to a single frame to be drawn progressively.

However, i get my information from the popular knowledge of the internet. Let me know if you find out anything contrary to this, because this really interests me.

wiki from MythTV has this little interesting nugget
https://www.mythtv.org/wiki/Deinterlacing

I never really thought about that doing that. So maybe some LCD's can increase your fps with interlacing and still redraw everything progressively?

Either way, how would you even go about setting interlacing on the pc? I mean... theres no options in resolution to set interlaced is there?

I have a Proper monitor, not a LCD. If you read my sig, you would know that. AFAIK, Interlacing is useless on a LCD. CRU, SwitchResX, and all other resolution utilities have interlacing options.

 

[defaultluser]

You won't receive any performance boost at the simulation level, the full scene still needs to be drawn.

I disagree with this.

You're drawing half the frame size (interlaced frames are half the vertical resolution). Therefore it will draw a frame twice as fast.

But do be aware you're cutting your temporal resolution for fast-moving content, so you're trading response time for less clarity.

 

[serpretetsky]

I have a Proper monitor, not a LCD. If you read my sig, you would know that. AFAIK, Interlacing is useless on a LCD. CRU, SwitchResX, and all other resolution utilities have interlacing options.

Well then man... what on earth are you waiting for? Try it and get back to us

 

[serpretetsky]

Sorry to bump: OP, did you ever test this? Any results?

 

[KazeoHin]

I have a Proper monitor, not a LCD.

Soooo Tired of hearing this. CRTs =/= superior. A 'Proper' monitor doesn't have geometry issues or weigh more than the computer signalling it.

 

[Nenu]

I disagree with this.

You're drawing half the frame size (interlaced frames are half the vertical resolution). Therefore it will draw a frame twice as fast.

But do be aware you're cutting your temporal resolution for fast-moving content, so you're trading response time for less clarity.

Bollocks. It does not draw a frame twice as fast.
It draws half the frame.

 

[serpretetsky]

Bollocks. It does not draw a frame twice as fast.
It draws half the frame.

If you reread the part you quoted I don't think either of you are really disagreeing with each other.

He points out your drawing half of a frame and that therefore you are getting less clarity with each "half-frame" but getting increased response time when comparing drawing a "half-frame" vs drawing a "full-frame".

The question then becomes if it's worth it. You are only drawing half a frame, however you do draw the other half later. So all of the spacial detail is there.... it's just temporarily spaced out which isn't ideal.

 

[wizzi01]

Soooo Tired of hearing this. CRTs =/= superior. A 'Proper' monitor doesn't have geometry issues or weigh more than the computer signalling it.

Best to just ignore him. Most of his posts are troll posts.

 

[MangoSeed]

You're drawing half the frame size (interlaced frames are half the vertical resolution). Therefore it will draw a frame twice as fast.

No that is not how rendering works. Even if the final output is an interlaced frame the card still has to process all geometry and full resolution intermediate buffers (shadow maps, g-buffer etc). It will definitely not be twice as fast.

 

[defaultluser]

No that is not how rendering works. Even if the final output is an interlaced frame the card still has to process all geometry and full resolution intermediate buffers (shadow maps, g-buffer etc). It will definitely not be twice as fast.

Point taken, you may hit geometry limits before you get anywhere near halving the frame time.

In my defense, I was responding to a pointless question from rabidz7, so I put zero brainpower into it

 

[xorbe]

Soooo Tired of hearing this. CRTs =/= superior. A 'Proper' monitor doesn't have geometry issues or weigh more than the computer signalling it.

Depends on your needs. A proper monitor is also inky black in a dark room ... unfortunately the ideal screen still doesn't exist.

 

[hajalie24]

I don't see how it would. I've hooked up my computer to a 1080i CRT TV before, Windows sees a resolution of 1920x1080 at 60HZ, and so do games. The TV would be the one to decide which rows get refreshed.