night time rendering problem

[domer1322]

can anyone tell me how to fix this rendering problem ? I want to show a night time render (with RenderWorks 2013) but many image props render as if they have a full strength of light hitting them, while everything else is properly dark.

Any help is appreciated.

PS: I tried to attach a jpg image, but couldn't figure out how to do it on this forum page.

[Tamsin Slatter]

Hi

You need to edit the textures on the plants (you'll find them on the Resource Browser), and turn off Glow reflectivity. This is on by default with plants - and serves the purpose of hiding the inevitable shadow that you will see from the crossed planes of the image prop. So, in effect, the plants themselves are currently emitting light.

It's a bit painful, because you'll have to show the plants with or without glow. I have found a good compromise is to reduce the glow (instead of turning it off) to around 40%. As long as you employ indirect lighting on your daytime render, your plants will look fine, but will calm down a lot in your night time render.

Hope that helps

[michaelk]

When you create an image prop there's a checkbox for "Constant Reflectivity". UNcheck that.

If that ship has sailed, then simply edit the texture for each image prop. In the RB there will be a texture for each image prop. Probably called something like "____________ Prop Texture".

Right click on it in the RB and choose edit.

Under Shaders : Reflectivity change the pulldown from Glow to None. Or click edit next to the pull down and change the brightness from 100% to something much lower.

Repeat for each image prop.

Save and archive before you do this. You may want to create duplicates of the image props. One for day and one for night.

hth

mk

[jnr]

Tamsin:

On a slightly similar subject, I recently upgraded to Designer and need to make some image prop trees more transparent for a urban design project. I had thought all I had to do was change the transparency slider in the attributes palette, but alas this does not work. Have tried to adjust the tree prop texture (frog) image but could not figure that out either.

Am I missing something obvious? Am on a deadline and could use whatever help you could offer.

thanks

-J

[Jonathan Pickup]

add a transparency map to the image prop texture.

[jnr]

hey Jonathan thanks for chiming in. how do I do that? and what time is it down there?

am using the supplied frog trees.

[Bryan G.]

In the resource browser, go to image textures, find the plant image you are using and right click. Then go to Edit. from there you will see the Transparency option. This is where you can add a mask.

I believe this is what Jonathan was referring to.

[Tamsin Slatter]

But the image prop already has its transparency shader set to Image Mask. This is what makes the area around the image transparent. So, I don't believe you will also be able to add overall Plain transparency to the image prop without losing the mask.

You could experiment with overlaying viewports that have different opacity settings - but it probably won't work because you'll get messed up shadows.

[ray isaacs]

yes, i think tamsin is right. as far as i can tell, there isn't a good way to make selected objects like trees transparent in 3d views, using transparency options on any of the various settings (layer, class, image, texture...). if someone knows a way to do this, i would love to hear it. that would give a lot more rendering and presentation possibilities and save a lot of photoshop time. i intended to add this to the wish list for some time now. i think i will.

cheers,

ray

[bcd]

One simple (brute) way is to place foreground trees in a separate Viewport - render and turn the VP opacity down

[bcd]

Well whadayaknow,

This was possible in VW2012. It seems like this feature has been removed in the VW2013 upgrade!

[Tamsin Slatter]

You can open your tree images in Photoshop, select the pixel, make paths, copy the paths to illustrator, select them, paste them into Vectorworks, covert to 3D Poly, rotate 3D to make 'em stand up, and THEN apply a transparent texture! But you will need to make sure they are facing the way you want.

Hope that makes some semblance of sense!

[Tamsin Slatter]

Hmm - you're right - you can no longer edit the opacity of a viewport. Even if your default opacity is set to less than 100% when you create the viewport, the resulting viewport is still 100%.

[Benson Shaw]

You can open your tree images in Photoshop, select the pixel, make paths, copy the paths to illustrator, . . .

That's a good way of creating a 3d object to make a fairly realistic semblance of the trees represented in the image prop. A big advantage is that it does not depend on image mask textures, so will appear in non rendered views and in Hidden Line renders. A disadvantage is the huge number of lines and other objects in the completed tree object.

But you will need to make sure they are facing the way you want.

Mimic the image prop to add depth by making a symbol and duplicate/rotate to make a cross plane object.

If realism is not required, or the object count causes too much CPU overhead, draw a simpler 3d tree outline in Vectorworks and cross plane it (even 3 or 4 crosses for a really dense look). I have a small library of these made of trunk, branch and canopy objects. Color and transparency of the various elements are controlled by class. The symbols are scaleable. They are a bit cartoony, rather than realistic, but often serve my purposes.

-B

[Monadnoc]

You can create semi-transparent Image Props but it has to be done at creation. Just use a Black & Grey image of the tree silhouette instead of a Black & White one, then choose "Use Mask", then select ?Grayscale Pixels? as Source For Mask. The "darkness" of your grey in the image will determine how transparent it is. This isn't perfect, but it does basically what you're asking.

The PDF has a little higher resolution, plus three examples for comparison, Open GL, CRW, plus a CRW done with all the trees at 100% so you can get an idea what's showing through in the other two.

Coming from the Landscape Arch field, I actually don't like the trees made transparent at all - I want to see the trees set off the building, not see through them. BUT - I realize this is a very common technique in architectural visualization, so I am very curious as to how much fading all of you who do/would use this technique prefer. So which percentage of opacity do you all think looks best?

Here's a (little) more in depth description of how I did this:

Create Semi-Transparent Tree Image Prop

Model > Create Image Prop... > Import an Image File > browse to color image file and select it > name it and adjust Height and Width and other settings as desired (I use everything selected, including Create Symbol), SELECT ?Use Mask?, click on ?Create Mask?? > Import an Image File > browse to your Black & Grey image of tree silhouette and select it > choose ?Grayscale Pixels? as Source For Mask > click ?OK? to create Image Prop. I like to be able to see the name of my image prop when I select it in my drawing, so I Edit ?Symbol Options? and de-select ?Convert to Plug-in Object? in order to have it insert as a 3d symbol. Then I re-insert it, and delete the Image Prop VW placed automatically.

To extract the tree image from existing Xfrog image props, right click on texture in Resourse Browser and choose ?Extract Image(s)? and then navigate to where you want to put it. In my VW 2011 the button always says ?Open? instead of ?Save?, but it still works when you get to where you want to put it and just click ?Open?, it saves it. Go figure.

Edited February 12, 2013 by Monadnoc

[Tamsin Slatter]

Excellent tips there! I like the crossed planes idea. I had not thought about the grayscale transparency for image props. Very cool.

[Benson Shaw]

Good one, Brian! I never explored the grayscale transparency. There is soooo much to learn (and remember if possible).

-B

[ray isaacs]

a lot of really good suggestions here. now to find the time to practice them.

ideally, what i would like to do is to have class and layer opacity settings work in 3d views as they do in 2d. then whole classes of objects or layers with overlays or underlays could be very easily adjusted--just like in the top/plan. it sounds reasonable to me. but, is there a technical hurdle--perhaps with rendering--that makes this impossible to implement? hence having to make objects one-by-one, using textures to control opacity?

to benson's point about realism. i don't care that much about realism. i'm more interested in have the flexibility to creat effective presentations with a balance between abstraction and realism. vw offers this to some degree and learning tricks helps. but, i get annoyed at rendering software in general pushing for realism at the expense of creative expression.

ray

[bcd]

Oh bring back Piranesi support!!

[Benson Shaw]

i'm more interested in have the flexibility to creat effective presentations with a balance between abstraction and realism

I'm with you, Ray.

All drawings are in some way misrepresentations of "reality". 3d models on screen or paper are a flat simulations of 3d space, colors and light are manipulated for effect, edges are manipulated or emphasised, image props of people or plants are posed, urban grime is scrubbed away, verticals and horizontals are perfect, pavements have no cracks or holes, etc, etc, etc.

There are even arguments about sensory interpretations of "reality". Eyeballs focus selectively, ears selectively ignore, brains filter and interpret, effects of cultural norms, etc, etc, etc

I often marvel at detailed models, scenes and renders, even try to achieve them on occasion. But I wonder that presenters and audiences are so needy or so fearful of a sudden inability to focus on graphic information, so unable to apply imagination as directed by the drawings, to interpret as they do in other aspects of life.

-B

[domer1322]

I'm just writing to say thanks to the initial response on the night time renders ... it worked ... and now these other comments have taught me a couple things too ....

[jnr]

thanks to everyone for responding, especially after I inserted myself into the thread, pulled the pin out of the grenade and rolled it into the message board. My problem seemed relevant to the thread. This is some valuable info and I agree that it would be nice if the software could handle transparency without having to use more applications (photoshop). And yes there's so much to still learn, it makes my head swim, even after all these years. Bummer about no viewport transparency in 2013.

Rendering for presentations is a big part of what we all do. NNA has always promoted and had the advantage of being one of the best one-stop shopping CAD applications out there. Lets hope the powers that be will recognize the value of a 3D transparency option. It would make this vastly more efficient.

-J