Domino Marama's crossed prim sculpty method

Over the years, I have tried Blender then given up. But finally, while I use AC3D and Wings to create sculpties, I wanted to use the texture bake abilities of Blender - so I gave it another try. Many thanks to Domino and Gaia, as they made this latest trip so much easier

So after creating and painting a couple of items with great success, I wanted to build some low prim plants, bushes and trees and started using Domino's simple process to create a sculpty that gives two crossed planes as one prim. Everything worked fine outside of SL - looked excellent. Then I imported it into SL!

I have attached a pic of what seems to be a nasty artifact of a plant texture applied to the prim. I have tried 6-7 different textures from different sources - all produce the same effect. I assume an alpha bug, but I'm curious about the "sawtooth" effect. Any thoughts?

It is not a big issue with small plants close to the ground - but larger eyelevel objects do not look good.

gryff

I have a "crossed prim sculptie method"??!?!?!?

If you mean the modelling tip on scaling alternative rows on a cylinder, then the easiest way to get cleaner alpha on it is to rotate the uv map 90 degrees before baking. In SL set the sculptie stitching to planar.

Domino wrote "I have a "crossed prim sculptie method"??!?!?!?"

Well when does a "tip" of a few steps become a method? How many steps necessary for it to become a method.?

Will give the additional rotation before baking and stitching change a shot.

TGA for all the info, scripts, tips and methods you provide on this forum. You and Gaia have taken a lot of my reticence away and made the learning curve a lot shallower for Blender

gryff

Brilliant!!!!

And just to show the success of Domino's latest "tip" (coughs) here is a "before and after" pic.

gryff

It's a method now!

If I had to draw a distinction, a tip will get you started playing about in the right area, a method includes all the steps you need to do

Does anybody know why rotating the uv-map before baking does make such a big difference with alpha textures ? Is this a detail due to blender ? Or due to some feature of sculptie maps ? Or due to a feature of Domino's scripts ? Any explanation for this effect is highly appreciated

thank you in advance
regards,
Gaia

The cause is the triangle draw order in SL. Rotating the UV map changes the draw order of that sculptie's faces. This has the side effect of making the seams / poles on the wrong edges of the sculptie so the type needs to be changed to Planar in SL.

rough code speak:

for v = 0 to (PixelHeight/2) - 1
for u = 0 to (PixelWidth/2) - 1
draw faces for points v,u ; v,u+1; v+1,u and v+1,u+1
next u
next v

where 0,0 is bottom left of sculpt map. So rotating 90 degrees clockwise switches u and v effectively making the loops

for u = (PixelWidth/2) to 1 step -1
for v = 0 to (PixelHeight/2) - 1

So the rotation trick results in the faces being sent in a different order and with the quads split to triangles across the other diagonal.