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Teselations

#1

hello
i wonder if you boys help.

i’m trying to create a pattern from a flash texture that isn’t symmetrical but does tessellate.

what i mean is i want to make a pattern demonstrated by this - http://www.vincentoliver.co.uk/things/TILEDEMO2.JPG. in fact, that’s the very pattern i’ve made. Notice that the tiles are not mirrored at all and that there is a sideways shift in every other row. Like this:

…b…b…b
b…b…b…
…b…b…b

i’ve tried positioning many quads, but that’s very processor intensive (the pattern i very animated).
by using one quad and playing with the scale pins i can this - http://www.vincentoliver.co.uk/things/TILEDEMO3.JPG, but as you can see, that’s not what i want at all.

you’re all clever chaps/chappettes - any ideas?

#2

the ways of tiling textures within in the directx fixed function pipeline are quite limited. The Address (EX9.SamplerState) node helps switching between these when connected to a Texture.
Note that not all graphic cards support all modes.
mathematically spoken directx supports from the 17 possible symmetry groups only p1, pm and pmm symmetries.

see http://en.wikipedia.org/wiki/Wallpaper_group

to do the other symmetry you could
(1) setup a spread of graphical objects like quads. and control position, scaling and rotation with spreads. performance should not be a problem when done properly. Resample and Cross will come handy.
(2) to optimize your particular case you can make one quad with a repeated texture for one line, and draw a quad for each row. the alternating x-shift is what vvvv´s spread semantics is made for.
(3) load one x file with a grid of triangles having clever texture coordinates. or create this vertexbuffer from within vvvv.

#3

thanks oschatz

worked a treat!

i used option 2 in the end, quite a simple patch really, and i’m really really delighted with the outcome:

http://www.vincentoliver.co.uk/things/filetile.JPG

I’m really surprised at how easy/effective it was. : )

#4

there is one little problem - this little line. during the performance i will be zooming in so it will be visable. there isn’t a vertical one, just horizontal.

also - is there a way of making the gdi texture more hi-res without making the flash renderer window bigger? as you can see, it’s looking pretty grubby zoomed in like this.

(see attachement)

DARN LINE.JPG (69.9 kB)

#5

youre patterns look great!

this little line

as the line is a sharp one - it´s probably not on the texture, but between the quads. the exact source of this artifact needs some thinking, but you could try

(1) shifting your quads upwards by 1/height
(2) change the background color of the renderer to make the lines white
(3) use a Blend node set to add

tell us your results. looks like a bug.

is there a way of making the gdi texture more hi-res without making the flash renderer window bigger?

no, you get what you have paid for. the flash renderer can not render to an offscreen buffer. for a future project try a EX9 Renderer showing 3d objects with textures for generating the patterns and another doing the tesselations :)

#6

you like it? thanks. i’ll get you in free to the show, if you like - for all your help. where do you live?

used the blend node, but add didn’t help much - used ‘colour as alpha add’ and changed the background colour of the renderer from white to black. : )

shifting the quads around just made it worse

shame about the quality things - looks awful… but it’ll just have to do. my labtob decided it didn’t want to run the patch unless i made it smaller, too, which made me unhappy.

didn’t even understand this:
“try a EX9 Renderer showing 3d objects with textures for generating the patterns and another doing the tesselations :)”

thanks again - more questions coming soon

not bad.JPG (68.7 kB)

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