Read frame number from VFB

[prima_commerce]

Is there a way to read the frame number that is currently rendering from V-Ray's VFB? I would like to use that value to drive the file output name.

Here is the code that I am using as a pre-render script. It works only for the current frame that is set in the 3ds Max time slider.

mat = sceneMaterials["myMat"] /*Material to get names*/
matNo = (mat.switchNum as integer)
matObj = mat.switchMtl
f = currentTime.frame /*??? want to get frame number that is currently rendering*/
matName = matObj[f+1].name

rendSaveFile = true
fileLoc = "C:/Users/xyz/Desktop/"
fileExt = ".png"
rendOutputFilename = fileLoc + matName + fileExt​

Found solution to read out which frame number is rendering, but still can't get that value into Pre-render script.

fn myCallback = currentTime.frame as integer
callbacks.addScript #prerenderframe myCallback id:#myCtCallback​

I appreciate any help!

[hermit.crab]

The reason it doesn't work is that, unlike Maya, in 3ds Max there isn't a "Pre-render frame" script (only pre-render, which happens once even for animations). Also, note that the Render Setup has an old issue, which does not let MaxScript refresh the render settings. It is bypassed by passing a renderSceneDialog.close() and renderSceneDialog.open() line.

I modified your script so that it works without the need for a pre-render script. It works as a "manual" animation rendering, running the script after every frame:

fn manualAnimationRender = (

startFrame = 0
endFrame = 2

for i = startFrame to endFrame do (
renderSceneDialog.close()
slidertime = i
rendTimeType = 1
mat = sceneMaterials["myMat"]
matNo = (mat.switchNum as integer)
matObj = mat.switchMtl
f = currentTime.frame as integer
matName = matObj[f+1].name as string

rendSaveFile = true
fileLoc = "C:\Users\xyz\Desktop\"
fileExt = ".png"
pngio.setType #true48
pngio.setAlpha true
rendOutputFilename = (fileLoc + matName + fileExt) as string

renderSceneDialog.open()
max quick render
)
)
try (manualAnimationRender())catch()​

You can check the pngio methods here.
Also, note that for the script to work properly, the Time Output should be set to Single frame, hence why I've added the rendTimeType = 1 line.