moving quads

Blitz3D Forums/Blitz3D Programming/moving quads

RifRaf

(Posted 2004) [#1]

Hi all. im having a hard time with somthing.. maybe one of you can help me out.

I am making a grid(bunch o quads) wich share verts.. 4
verts per 2 tri.

After its created I want to select any quad I want and move its verts on the z and or x axis , the connecting triangles should stretch

any help yould be appreciated..

Ziltch

(Posted 2004) [#2]

I wrote this to create function for the same reasons? The code could be cleaned up a bit.

createsquare(segs#=2,parent=0)
Segs = how many segments per side.
i.e.
grid=createsquare(10)
Creates a 10x10grid with shared verts.

http://www.blitzbasic.com/codearcs/codearcs.php?code=463

Also in the archive is the Mesh terrain by BadJim
http://www.blitzbasic.com/codearcs/codearcs.php?code=362
It does a what you need and more!

RifRaf

(Posted 2004) [#3]

thanks but ive gotten that fAr. I want to select the verts in a specifed quad.. how can i do that. ok if i pick one triange.. how can i determine the other triangle that goes with it??

HMM it isnt as simple as picking.. getting picked triangle index number.. then if its odd the very next index it it? or if its even the prev index is it??

Ross C

(Posted 2004) [#4]

You could set up a type collection with each quad in it. Then have a type object for each quad, with the field

Type quad
   Field start_index
End Type

Now Store the index value of the first vertex created for each quad. Then use camerapick command and return the picked triangle. Then, use the

TriangleVertex ( surface,triangle_index,corner )

to return the index value of ANY vertex (corner can be 0,1 or 2). Now, loop through all the types, and compare the index number to the index value held the the type like so...

for q.quad=each quad
   If q\start_index=> picked_index and q\start_index =< picked index then
      found_index=q\start_index
      Exit
   End If
Next

This will return the picked_index values assciated start index.

Now you have that number, you know which one of the vertexs you have selected basically.

found_index-picked_index= the corner of the quad.

RifRaf

(Posted 2004) [#5]

woot! thanks