Cross trees not working in VRay

[CookiE]

I often use cross trees with tga textures that have a mask over what i want to be transparent

I put the texture in the diffuse and instance it down to opacity in a standard material

and make the mono channel output to alpha

this works perfectly other than shadows in scan line rendering and use to work in my old version of vray but im now using vray 1.5rc2 and it no longer works

is there a setting i have to click on or off to make it work in the new vray or is there a different way i have to make the materials now?

 

Hopefully not much a major to fix

 

And thanks in advance

[Brian Smith]

you should use the instance option because when you change from mono in the opacity channel it will change in the diffuse channel. why not just use the convert scene to vray feature...this should do what you want. you made no indication that you were using vray materials but i'm assuming you are.

 

btw, you said 'except in scanline'...you can use the opacity map to create shadows automatically, both for raytraced and adv. raytrace...can't tell if you know that or not

[CookiE]

Im still a noob with vray

i am using half vray and half standard maps

with the trees they are standard and i am using the instance option like i said above

Im not sure what you mean by convert scene to vray feature...

 

and how can i create the shadows using this option when i do it, it creates a shadow of the plane not the opacity map so instead of getting a nice tree shadow i get a box shadow...

 

To create my cross tree:

I create a plane the size i need apply the materail convert it to editmesh then copy rotate it 90degrees then attach them together and scatter them using the scatter option, is there a better way to do this?

 

 

Also i have tried using a vray material with a opacity map witch did work but because theres a cross trees to get them looking 3d i apply a 50 self illumination but i cant find where to do that with a vray material

[Brian Smith]

might want to check out the article on vegetation (below)...we talk at length about opacity maps and other things you're looking for. as far as the scene converter feature, right click in the active viewport, and select vray scene converter' from the quad menu...all your materials and raytraced shadows are automatically converted.

 

http://cgarchitect.com/upclose/VI/default.asp

[CookiE]

Those help files will be well used but doesnt say anything about the problem that i am having with vray, and i tried the conversion thing and that didnt fix the prob either

[Brian Smith]

describe exactly what you're trying to do and list the steps that you are doing...i'm missing something

[CookiE]

describe exactly what you're trying to do and list the steps that you are doing...i'm missing something

 

Trying to create a opacity material for a cross tree

 

Here is what is happening

 

 

All the black in the trees are ment to be transparent

 

here are the settings

 

 

These settings all work fine in scanline but wont work in vray

[Chad Warner]

Have you tried making a Vray material using the same tga's? I don't know that it will solve your problem, but it would be something to try.

[CookiE]

Have you tried making a Vray material using the same tga's? I don't know that it will solve your problem, but it would be something to try.

Yeah i have but that was another thing that i asked about

If i do this it works ok but is way over bright and doesnt give the lighting i need

I use a 60 self illumination to make the tree look more 3d makes the cross look less of a cross or none at all if ya get it right and i cant find any option to do this in the vray material

[Brian Smith]

The only reason I can possibly imagine why you can't use the opacity map to create your shadows is one of 2 things: you're using ray-traced shadows (which dont work with vray), or you're using adv. ray traced without the Optimization option enabled. By default, Optimization is not enabled and you don't get the correct shadows. Enable it and you will (it's within the Optimizations rollout in the command panel). If you're using vray shadows and vray materials (which you should anyway), there wont be a problem.

 

Did you find how to convert the entire scene to vray materials and shadows? You really should do this because you'll get better and faster results.

[CookiE]

The only reason I can possibly imagine why you can't use the opacity map to create your shadows is one of 2 things: you're using ray-traced shadows (which dont work with vray), or you're using adv. ray traced without the Optimization option enabled. By default, Optimization is not enabled and you don't get the correct shadows. Enable it and you will (it's within the Optimizations rollout in the command panel). If you're using vray shadows and vray materials (which you should anyway), there wont be a problem.

 

Did you find how to convert the entire scene to vray materials and shadows? You really should do this because you'll get better and faster results.

 

Yeah i managed to convert the scene but the shadows are not the problem

the problem is the opacity map is not going opaque but i will have a look into this shadow thing i have been using shadowmap with a high map size and applying a projector map from the sun for shadows.

But would rather not have to do that so will look into what you have said

[Brian Smith]

i recommend staying away from shadow map...they consume a lot of memory and to get the same quality as other shadow types, you have to set the map size so high, the render times are excessive.

 

might want to take a look at this...it's from the Insider article of vegetation. it's a complete scene with trees like you want and everything else. it has some good render settings also

 

http://cgarchitect.com/upclose/VI/Week10/2D_trees_animation.zip

[CookiE]

i recommend staying away from shadow map...they consume a lot of memory and to get the same quality as other shadow types, you have to set the map size so high, the render times are excessive.

 

might want to take a look at this...it's from the Insider article of vegetation. it's a complete scene with trees like you want and everything else. it has some good render settings also

 

http://cgarchitect.com/upclose/VI/Week10/2D_trees_animation.zip

 

 

Thank you i will check it out

the only reason i use shadowmap is because it doesnt give a harsh straight line shadow edge it fades off and not sure how to do that with adv raytrace...

 

But ill check out the tree thing and see if i can work it out

[Brian Smith]

it's really easy with vray shadows (which provide the best results in terms of appearance and render times)...just enable the Area Shadow option and play with the u,v,w sizes. The larger the sizes the more blurring the shadows. But remember, anything in vray that blurs takes longer to render. Fortunately, this blurry effect is about the least guilty.

[Nic H]

bizzare problems indeed. Id def use area shadows, they arent much slower really, and if it for a still make it invisible to cam so it casts shadows and comp it in in PS.

 

have you tried just seperate opacity and diffuse maps rather than a tga with a alpha channel imbedded?

[CookiE]

bizzare problems indeed. Id def use area shadows, they arent much slower really, and if it for a still make it invisible to cam so it casts shadows and comp it in in PS.

 

have you tried just seperate opacity and diffuse maps rather than a tga with a alpha channel imbedded?

 

 

Only way i know how to make a opacity map

Still learning but everything i read im learning