the glass material become black in indigo 2.4.13

[chiataimakro]

nothing went wrong with this material when previewing, but when i started rendering with the whole scene...

i m new to indigo 2.4, this never happens in 2.2

[dougal2]

Which version of Blendigo is that ?

[Borgleader]

a) Are the cylinders closed volumes? From this angle I cant see if the end caps are present
b) Did you check that your normals are correct?

[CTZn]

I second borgleader.

Absorbtion may be too strong.

It is not good to interrsect glass and other materials. You must change the column or the walls (boolean difference plus a distance between surfaces).

[chiataimakro]

Which version of Blendigo is that ?

blendigo 2.4 stable. maybe i should rebuild this material in 2.4, instead of moving it to 2.4 from 2.2

[chiataimakro]

a) Are the cylinders closed volumes? From this angle I cant see if the end caps are present
b) Did you check that your normals are correct?

thankyou but i m quite sure there's nothing wrong in modeling: it does have caps and, all face normals are correct. this model works quite well with indigo 2.2

[chiataimakro]

i replaced the glass material with a diffuse one. it's still black.

it's a shame that i have to switch the whole project back to indigo 2.2. at least in 2.2 everyting works.

btw why shouldnt i intersect glass meshes with other meshes, that i always do?

[Headroom]

btw why shouldnt i intersect glass meshes with other meshes, that i always do?

It may not really help you to fix this particular problem but it is generally a good practice.

The reason for not intersection Glass are the same reasons why glass materials shoulsd only be assinged to closed volumes e.g cylinders with caps.

Glass has a medium inside so to speak. When you intersect Glass with another material indigo needs to know which of the two need to be rendered. For example the typical wine glass filled with wine is modelled with two intersecting volumes One for the glass and one for the wine. You would need to use the "precedence" setting to tell Indigo which of the two materials to render in the intersecting/overlapping volume.

[chiataimakro]

You would need to use the "precedence" setting to tell Indigo which of the two materials to render in the intersecting/overlapping volume.

thankyou for your explaination, i m now changing the settings. btw, as you described, intersecting two glass material is not good. but what about intersecting glass with non-transparent materials like phong or diffuse? in which order indigo considers about them?

[CTZn]

as you described, intersecting two glass material is not good

if they have the same precedence setting

Precedence allow nice glass volumes intersection.

Because precedence is only for mediums (glasses, gases, liquids etc), glass and other opaque materials must not intersect for a guaranteed accuracy. There must remain a minimum space of about 0.25 millimeter between such surfaces.

Is it the same IGS file wich works with Indigo 2.2 and don't with 2.4.3 ?

Did you try Indigo 2.6.1 ?

[chiataimakro]

well yes the IGS from 2.2 behave abnormally in 2.4.13

i tried the 2.4 exporter, the same result

now i m gonna try 2.6. good luck to myself. and everyone here are very kind thankyou!