How do you load an image on a grid with the colors on the primitives ?

[AntoineSfx]

It looked like a simple thing to do , but I can't get it exactly right.

Can you fill a 4x4 grid (5 rows, 5 columns, 16 poly, 25 points) exactly with a 4x4 pixels png image ?

Possibly using AttributeFromMap SOP, but targeting prims somehow.

 

 

 

Edited February 17 by AntoineSfx
Removed the attachment, it was unpractical

[konstantin magnus]

Put this in a primitive wrangle:

string img = chs('image');
vector bb = relbbox(0, v@P);
vector uvw = set(bb.x, bb.y, 0.0);

v@Cd = colormap(img, uvw);

 

[AntoineSfx]

Perfect

I wrote this point wrangle that is doing the same thing,  

This sets up a grid so that each point is actually at the center of the pixels (in UV space) and you can just use AttributeFromMap on it and it works; assuming that w and h are the width of the image in pixels

int w=chi('w');
int h=chi('h');

for (int x=0; x<w; x++)
    for (int y=0; y<h; y++) {
    
    int np = addpoint(0,set(0,x,y));
    vector  uv;
    uv.y = float(x)/w + 1/2.0/w ;
    uv.x = float(y)/h + 1/2.0/h;
    
    setpointattrib(0,"uv",np,uv,"set");
    }

 

Edited February 17 by AntoineSfx