[Closed] Use bitmap from memory with directx material

I’m trying to figure out how to make a directx material display a bitmap thats been modified via maxscript in the viewport, without saving the file for each change. This works fine for standard materials:

--Create mesh with standard material
theObj = Plane length:10 width:10 pos:[0,0,0]
theObj.mat = standard()
theBMT = bitmaptexture()

--Create and assign bitmap to material
desktopPath = (getDirectories ((systemTools.getEnvVariable("USERPROFILE"))+"/Desktop"))[1]
pngio.setType #true24
thePNG = bitmap 16 16 filename:(desktopPath + "testMap.png") color:red
save thePNG
theBMT.bitmap = thePNG
theObj.mat.diffusemap = theBMT

--Modify bitmap
setPixels theObj.mat.diffusemap.bitmap [1,1] #(black,blue,green,red,orange,yellow)
showTextureMap theObj.mat off
showTextureMap theObj.mat on

But if we do the same for directX materials nothing updates in the viewport:

--Create mesh with DirectX material
theObj = Plane length:10 width:10 pos:[0,0,0]
theObj.mat = DirectX_9_Shader()
theObj.mat.effectfile = (getDir #maxroot) + "maps/fx/colortest.fx"

--Create and assign bitmap to material
desktopPath = (getDirectories ((systemTools.getEnvVariable("USERPROFILE"))+"/Desktop"))[1]
pngio.setType #true24
thePNG = bitmap 16 16 filename:(desktopPath + "testMap.png") numframes:1 color:red gamma:1 pixelAspect:1 channels:#() hdr:false
save thePNG
theObj.mat.Tex0 = thePNG

--Modify bitmap
setPixels theObj.mat.Tex0 [1,1] #(black,blue,green,red,orange,yellow)
showTextureMap theObj.mat off
showTextureMap theObj.mat on

Is there a way to solve this in Max, or may the FX material itself needs to be modified somehow?