Parent and Z value?

Questions
#1

See this code…

local function draw_a_die(posx, posy, sizex, sizey, contents, guiname)
	math.randomseed(socket.gettime()*10000)
	local die = gui.new_box_node(vmath.vector3(posx,posy,1), vmath.vector3(sizex,sizey,1))
	gui.set_color(die, vmath.vector4(1.0,1.0,1.0,1.0))
	local dielabel = gui.new_text_node(vmath.vector3(posx,posy,1), math.random(1,6))
	gui.set_color(dielabel, vmath.vector4(0.0,0.0,0.0,1.0))
	gui.set_font(dielabel, "NormalSans1LARGE+")
	gui.set_parent(dielabel, die)
	gui.move_above(dielabel, die)
	gui.set_id(die, guiname)
end

if you remove gui.move_above the number disappears
if you then remove the set_parent the number appears
just to be sure using keep scene transform value doesn’t matter

What is the relationship between parenting an object and Z value?

Obviously I can get this to work but in my way of thinking setting the parent wouldn’t have necessitated the moving the text node above the box node.

#2

The z-value isn’t really used in the gui at all. The order in which nodes are rendered is controlled by the hierarchy of nodes and/or their layers. The z-value is not used for sorting.

BUT the z-value still has an effect, namely that if the z-value of a node falls outside of the near and far range in your render script it will not be rendered.

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#3

Ok that explains Z value a bit more but why is the behavior I’m experiencing happening when it seems like it shouldn’t. That said I did make some changes that make this a bit moot other than understanding why things happen the way they do in the code above.

#4

So this may have to do with an issue of absolute vs. relative coordinates between the imagery and the stencil itself. Going to play with it more and see.

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#5

Still not getting this to work – @britzl can you do the simplest build of a dynamic stencil and see what you get? Just get both a plain pie_node to stencil a plain box_node and then also to stencil a box_node that is displaying a dynamically loaded texture… I’ll keep trying further but a second run at it today is still failing to work as expected.

#6

Ok I got it to work but not as I expected… I’ll post more in a bit but this all still needs a bit more clarity :confused:

#7

Ok, waiting for your conclusions!

#8

Well the thing is mostly what I wanted to do was stencil a texture to a circle or other shape. Originally my [somewhat stupid] assumption was to load the texture to a box_node then stencil it with a circle or other shaped node. Then of course I realized if I just load the texture into the circle node I can achieve most of the same objective just bypassing the melding of two nodes. So I did that.

However, this still doesn’t quite explain why the first process isn’t working and it has some usefulness still because in that version I can change the sizing of the underlying box node to achieve certain effects that I can’t if I just push the texture to the pie_node itself.

Originally I thought the problem was that I needed to ensure that the box_node used 0,0,1 as its origin position since it’s being parented and stenciled by the pie_node but that isn’t helping.

So I’m still trying to achieve a box_node w/texture (loaded from file) stenciled by a pie_node parent and for that to easily display on a screen.

Though for now I’ve moved on because the direct method is working well enough for this sprint.

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