GetUVGen() for CHECKER_CLASS_ID

[istan]

auto tmap = (::Texmap *) ip->CreateInstance( TEXMAP_CLASS_ID, Class_ID( CHECKER_CLASS_ID, 0 ) );
BitmapTex * bmt = dynamic_cast<BitmapTex *> ( tmap );
StdUVGen * uv = bmt->GetUVGen();  // <<< FAILS!

I need access to "StdUVGen" but have no idea, how to get the pointer for a checker map.

All the samples just show it for a Bitmap map.

[denisT.MaxDoctor]

I confirm the failure.

Well... use the GetTheUVGen method of the Texmap class.

[denisT.MaxDoctor]

auto tmap = (::Texmap *) ip->CreateInstance( TEXMAP_CLASS_ID, Class_ID( CHECKER_CLASS_ID, 0 ) );
BitmapTex * bmt = dynamic_cast<BitmapTex *> ( tmap );

Why do you cast Checker to BitmapTex? It doesn't seem right...
But as I mentioned earlier, BitmapTex::GetUVGen doesn't work for me.

[denisT.MaxDoctor · Accepted solution]

You can cast after that:

	if (auto tex = (Texmap*)max_ip()->CreateInstance(TEXMAP_CLASS_ID, Class_ID(CHECKER_CLASS_ID, 0)))
	{
		UVGen* uvgen = tex->GetTheUVGen();
		StdUVGen* uvstd = dynamic_cast<StdUVGen*>(uvgen);
...
		

[klvnk]

you can't cast  a Checker map to a BitmapTex and expect it to work 🙂

do it this way...

Texmap *checkerMap = (Texmap *) CreateInstance(TEXMAP_CLASS_ID, Class_ID(CHECKER_CLASS_ID,0));
	StdUVGen *uvGen = (StdUVGen*)checkerMap->GetTheUVGen();

to be precise you should get a UVGen first, then check to see it thats a StdUVGen with UVGen::IsStdUVGen () then cast to StdUVGen, but hey ho 😄

[A012255]

You are right. This is it:

StdUVGen * uv = (StdUVGen *) tmap->GetTheUVGen();

[A012255]

Thanks to everybody!

[denisT.MaxDoctor]

We worked in parallel... 😉

It seems like the direct GetUVGen method BitmapTex is not functioning properly.

[klvnk]

I checked it in our exporter seems fine if it is an Actual BitmapTex 

[denisT.MaxDoctor]

	if (auto tex = (Texmap*)max_ip()->CreateInstance(TEXMAP_CLASS_ID, Class_ID(CHECKER_CLASS_ID, 0)))
	{
		UVGen* uvgen = tex->GetTheUVGen();
		StdUVGen* uvstd = dynamic_cast<StdUVGen*>(uvgen);
...
		

My understanding is that GetTheUVGen returns StdUVGen in general... otherwise dynamic_cast should not have worked. Wouldn't it?

[istan]

UVGen* uvg0 = tex->GetTheUVGen();
if (uvg0 && uvg0->IsStdUVGen()) {
	StdUVGen *uvg = (StdUVGen*)uvg0;
	uvg->InitSlotType(MAPSLOT_ENVIRON);
	uvg->SetCoordMapping(UVMAP_SPHERE_ENV);
}

Look at this code snippet from the examples. IMHO it's self explaining (if it's working).

For me all clarified. Thank you Denis & klvnk.

[denisT.MaxDoctor]

Here is what the header says:

virtual BOOL IsStdUVGen() { return FALSE; } // class StdUVGen implements this to return TRUE

virtual (!)

The question is: if it's not StdUVGen, what is it? The documentation mentions either StdXYZGen or a custom 🤣

[klvnk]

a custom implementation that derives from UVGen that returns false from IsStdUVGen

[denisT.MaxDoctor]

---

@klvnk wrote:

a custom implementation that derives from UVGen that returns false from IsStdUVGen

---

Yes. What is about StdXYZGen?

[denisT.MaxDoctor]

Haha! I found how easy to crash the MAX:

meditmaterials[1] = c = checker()
c.coords = StandardXYZGen()

... and try to open the Material Editor 😜

but for texmaps those need StdXYZGen it's safe:

meditmaterials[2] = d = dent()
d.coords = StandardUVGen()

PS. No! Both setting UV in place of XYZ or XYZ in place of UV will cause MAX to crash

This is interesting because I can't find a way to check what type of Map Coordinates a texture map class needs.