In sops,i konw how to do this.But in solaris,how could i bind the focus distance with a null?

Check the below post, but please also RFE for this. This should be built into Houdini (with a better implementation than mine, obviously):

https://www.sidefx.com/forum/topic/7088/#post-374564 [www.sidefx.com]

eikonoklastes
Check the below post, but please also RFE for this. This should be built into Houdini (with a better implementation than mine, obviously):

https://www.sidefx.com/forum/topic/7088/#post-374564 [www.sidefx.com]

Yeah,this should be a basic option.Sidefx please fix this in H20.

When using the transform to move the camera, the method mentioned above becomes ineffective. I used the 'wrangle' with the help of ChatGPT, and the following is the code：


matrix cameraTransform = usd_worldtransform(0,"/cameras/camera1");
matrix targetTransform = usd_worldtransform(1,"/pig/target_FD");


vector4 cameraPosHomogeneous = set(0, 0, 0, 1);
vector4 targetPosHomogeneous = set(0, 0, 0, 1);
cameraPosHomogeneous = cameraTransform * cameraPosHomogeneous;
targetPosHomogeneous = targetTransform * targetPosHomogeneous;
vector cameraPos = set(cameraPosHomogeneous, cameraPosHomogeneous, cameraPosHomogeneous);
vector targetPos = set(targetPosHomogeneous, targetPosHomogeneous, targetPosHomogeneous);



float distance = distance(cameraPos, targetPos);


usd_setattrib(0,"/cameras/camera1", "focusDistance", distance);

guan9287
When using the transform to move the camera, the method mentioned above becomes ineffective. I used the 'wrangle' with the help of ChatGPT, and the following is the code：


matrix cameraTransform = usd_worldtransform(0,"/cameras/camera1");
matrix targetTransform = usd_worldtransform(1,"/pig/target_FD");


vector4 cameraPosHomogeneous = set(0, 0, 0, 1);
vector4 targetPosHomogeneous = set(0, 0, 0, 1);
cameraPosHomogeneous = cameraTransform * cameraPosHomogeneous;
targetPosHomogeneous = targetTransform * targetPosHomogeneous;
vector cameraPos = set(cameraPosHomogeneous, cameraPosHomogeneous, cameraPosHomogeneous);
vector targetPos = set(targetPosHomogeneous, targetPosHomogeneous, targetPosHomogeneous);



float distance = distance(cameraPos, targetPos);


usd_setattrib(0,"/cameras/camera1", "focusDistance", distance);

You can't use distance to set focal distance, as focal distance is distance between planes, not points. The target point should be transformed into the camera's local space and the dot product with the z axis (or just the z component) used as the focus distance.

Hi,

I revised this and the follwing works well for me:

For completeness here's the vex for the planar distance between a camera prim and a focus prim with a variable to control which input the focus prim is sourced from.