Forum

DX11 Blend equivalents of DX9 Blend?

vvvv beta question
#1

I’ve been beating my head against this a lot lately when porting DX9 patches to DX11 - how to convert DX9 Blends to DX11 Blends?

The DX11 advanced Blend node has more pins than the DX9: there is a blend and an alpha blend type for source and destination. What is the difference, and how do they relate to DX9 blending?

In particular, I have two Blend (EX9.RenderState Advanced) cases I can’t figure out for DX11:

  1. Source Bland Mode: SrcColor Destination Blend Mode: InvSrcColor

  2. Source Blend Mode: InvDestColor Destination Blend Mode: DestColor

Thanks folks!

#2

After more headbanging (see Illustration No. 1) I figured out that it appears that by setting Source Alpha Blend to zero from the default of one, and setting Operation to Add from the default of Maximum, that it works like the DX9 version - at least with the things I’ve tried so far. I had naively thought the default settings of the new Alpha pins would be equivalent to the DX9 behavior.

Does anyone know of a good example on the web of all the DX11 blend modes? I have not turned up anything really definitive in my searches.

Illustration No. 1

#3

not sure if it helps but here is some discussion of DX9 blendmodes.

#4

Thanks joreg, that much I can find. But what about the other pins on the DX11 node:

Alpha To Coverage
Operation vs. Alpha Operation
Source Blend vs. Source Alpha Blend
Destination Blend vs. Destination Alpha Blend

How do the Blend operations factor in versus the Alpha Blend operations in the formula? What do the Operation “Maximum” vs. “Minimum” options mean in practice? The greatest/least of source vs. destination?

Being a very visual person, what I would really love to find/make is a chart showing the effects of the various combinations so I could just look up what I would like to accomplish, but I can’t find it anywhere.

#5

this might help: https://takinginitiative.wordpress.com/2010/04/09/directx-10-tutorial-6-transparency-and-alpha-blending/

© vvvv group