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Strange behaviour of light

vvvv beta general
#1

hi folks,

i have a little trouble with the light-node:

problem 1:
if i connect the “Light (EX9 Point)”-node to a “Box” via the “PhongPoint”-node it seems that the side of the box is somehow cracked down into two triangles.
and the light shows the border between the two triangles.
is this normal behaviour or is there some way around?

problem 2:
if i view the scene frome the side (via the camera node) the highlighted area seems to be placed wrong.
you can see this especially if the camera rotates from one side to the other.
any solutions/suggestions to this?

for a better understanding i added a sample patch to illustrate my problems.

i would be really thankful for a short (and quick) response
greetings from austria
david // quote

EDIT:
just found out, that if i use a grid with a high resolution problem 1 is nearly gone. but problem 2 still persists.

light.v4p (15.9 kB)

#2
  1. it’s to do with the resolution of the box. If you connect a fill(EX0.RenderState) node to your PongPoint and change the fill mode to WireFrame you’ll see the issue with the box.

One solution to this would be make you’re own box xfile with a higher res mesh.

  1. Can’t really see the problem (when using a high res grid). Looks right to me.
#3

thanks for the quick response.

for this project i solved problem 1 with a Grid (EX9.Geometry) and a higher resolution (10-20).

  1. maybe you’re right. to me it looks more like a mirror than a non reflective surface.

anyway. thanks again.
david // quote

#4

ad 2) the specular component in phong shading is computed as being reflective. that is by design. if you don’t like that you could set the specular component to black and only use the diffuse one or write your own shader.

#5

ah i see.
thanks for your answers joreg and xd_nitro

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