[noob] DX11 Shader Porting Problem

vvvv beta question
1

Hi all,

for the first time I’m trying to port a shader from shadertoys to vvvv.
As I’m not an expert in this field I just started comparing the code of different ported dx11 shaders to get a basic understanding…

the shader I am talking about is
https://www.shadertoy.com/view/MsSGWK#

I got stuck when I tried to find an equivalent for

vec4 ref = textureCube(iChannel0, normalize(reflect(rd, n)));
vec3 rfa = texture2D(iChannel1, (p+n).xz / 6.0).xyz * (8./d);

especially the textureCube part is really confusing to me.
I tried to replace it with texCUBE, but without any luck…

maybe someone can give me a hint in the right direction or even a probable solution?

thanks a lot

soriak

2

vec becomes float, as a rule of thumb.
you can have a look here for some other ports to get an orientation.

3

TextureCube filename <string uiname=“Texture Cube”;>;

will create a texture input pin, have a look at cubemap.fx (dx11) for further usage…

4

@ sebl

thanks, that’s exactly what i tried to do, the code snippet that I posted was the un-ported original… I replaced all the vec3’s and the other standard stuff, but the confusion starts when texCUBE asks me for a “sample Cube” instead of a Vector/float…

I assumed (by looking at the other shadertoy ports) that the “iChannel” variables work as colour inputs in vvvv.

variable declaration from the original code:

uniform samplerXX iChannel0..3;          // input channel. XX = 2D/Cube

@catweasel

thank you, that helped a lot! well, at least I thought so until i realised that the function call “texCUBE” still returns an error stating:
“intrinsic function doesn’t take two arguments.
possible intrinsic functions are
texCUBE(samplerCUBE,float3);”
etc.

after initializing with

TextureCube c0 <String uiname="Texture Cube";>;

and having the meso cube map connected to the pin
the following line still gives me the said error…

float4 ref = texCUBE(c0, normalize(reflect(rd, n)));

I fear I might be missing something that’s painfully obvious…

5

The file Cat mentioned has everything you need.

But basically you need to do two things, declare the (cube)texture, which you have done already, and then sample from it:

float4 myResult=c0.Sample(mySampler, uvw);
6

you’ll need to declare a sampler also (again see the cubetexture.fx file) and the uvw is coordinates for the cubemap lookup which in your case is the

normalize(reflect(rd, n)
7

nice, thank you!
I couldn’t find the texCUBE call in the cubetexture.fx and got confused.(so far this seems to happen a lot to me when it comes to shaders…) My bad. I’m gonna look through the file thoroughly and report back!

8

found the time to look at it again:
got it to work! thanks again!
now some other minor issues popped up, but i’m sure that’ll be doable!