Another semi transparent tree

[Alan Fraser]

As I'm working on several dozen of these things at the moment, I thought I could spare one for the forum. A detailed, generic 30 footer, semi transparent so as not to hide to much of your handiwork.

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tree_semitrans_30.skp

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[urgen]

...Good idea, Alan. Thanks... i shall apply it...

[mateo soletic]

Alan,
Thanks for sharing , the tree and the information.

[tomsdesk]

Another beauty, Alan...sure wish I could cowboy the pngs as well as you.

[otb designworks]

Thanks Alan! beautiful as always.

[richcat]

Thanks Alan

[Alan Fraser]

I developed the concept of a separate shadow caster a few years back. It adds a few extra faces but saves massively on edges...which can slow a model down just as much.

In a model such as this, (or a layered, multi-part Face Me) which uses a load of repeated transparent png images, I tend to use a separate element to cast a realistic shadow. This replaces the need to cut around all the edges on the individual pngs....which can add up to a heck of a lot of edges. Therefore I can leave all the pngs rectangular and simply turn off their cast shadow...replacing it with the shadow caster.

The shadow caster itself can take two forms. In the case of many Face me components it is usually just a billboard in the rough shape of the tree...painted with a small (64x64 pixel, I think) completely transparent png image; and the edges hidden.
In the case of this fully 3D tree it takes the form of about a dozen or so "leaf clumps" ...small perforated vector objects, painted with the same png. They are arranged randomly up through the canopy, so that they cast a reasonable shadow whatever the angle and bearing of the sun.

In this model, the shadow caster has an extra advantage in that it continues to cast a shadow, even though the canopy material itself has been turned down to only 30% opacity...so wouldn't.

[Alan Fraser]

A separate shadow caster has a load of other uses, too. For instance, I have seen a number of glass bottles in which , obviously, the glass material is well below 70% so doesn't cast any shadow in SU, however the cork or screw top is still opaque, so casts this weird looking shadow on the tabletop, totally detached from anything else. A separate shadow caster would solve that problem. I'm sure it must have lots of architectural uses as well. If you place it on a separate layer it's easily removable before export to a raytracer where it isn't needed.

You can make a png quite easily by simply opening a new 64x64 pixel (or even smaller) file in Photoshop...with no background...and just export this single clear layer as a shadow.png
Paint this onto any surface in SU and it will immediately disappear, but still continue to cast a shadow.

[Edson]

thanks for your generosity, alan. it serves me 100%.

i have been looking for a good semi-transparent tree for a long while. as i do not have the time nor skills to make one myself, your gift comes in very handy indeed.

and, by the way, where can i get other semi-transparent trees from? free or paid for, it does not matter.

regards.

[dylan]

Thanks Alan

[Alan Fraser]

Edson,
I make quite a few of these trees for FormFonts, but if you don't want to subscribe to that there are several other places that you can get 3D trees from that are low poly enough to be used in SU. The best is probably Got3D.

They are not semi-transparent, but can be made so by simply editing the opacity. They have demos which are downloadable. They are in 3ds format so are easily importable into SU...but you would need to get into the canopy and hide all the edges of the planes that carry the png files....and hide their shadow and add your own shadow caster.

[bertb]

Thank you, Allen
Nice and usefull
Bertb

[Aegedus]

very nice at all !!

Thxs
Aegedus

[el.antuan]

Really nice in deed!. Thanks a lot, Alan.

Regards from Spain :

Antonio.