Hello
Playing with the gl objects in GEM (0.90) on OS X (Pd 0.38-4
Extended, via Hans) , ive noticed that GEMglClearColor has 5 inputs,
one for the gem render chain, 2 - r, 3 - g, 4 - b and presumably 5 -
alpha, yet, changing alpha results in no change in the window
Changing the RGB values does, just like [color] to gemwin (as it
should).
Presumably, changing the alpha would act to let the scene draw 'over'
itself, and give an easy way to do trails/blurring. Jitter supports
this feature (not griping.. just saying :), any chance , or
workaround to get similar functionality, as I love the aesthetic of
it. Id rather not use snap2pix/snap2tex.
Thanks,
v a d e //
http://homepage.mac.com/doktorp/ doktorp@mac.com
On Sep 13, 2005, at 1:19 AM, vade wrote:
Hello
hiya,
Playing with the gl objects in GEM (0.90) on OS X (Pd 0.38-4
Extended, via Hans) , ive noticed that GEMglClearColor has 5
inputs, one for the gem render chain, 2 - r, 3 - g, 4 - b and
presumably 5 - alpha, yet, changing alpha results in no change in
the window Changing the RGB values does, just like [color] to
gemwin (as it should).Presumably, changing the alpha would act to let the scene draw
'over' itself, and give an easy way to do trails/blurring. Jitter
supports this feature (not griping.. just saying :), any chance ,
or workaround to get similar functionality, as I love the aesthetic
of it. Id rather not use snap2pix/snap2tex.
...ok, you have the correct inputs to the object, but there are a
coupla things to make sure of:
- the rgba inputs need to be 0-1
- after [GEMglClearColor] you need a [GEMglClear] that clears the
color buffer (GL_COLOR)
3. what is the gemhead ordering? Are you trying to clear everything
via [gemhead 1]? Or are you inserting this into every drawn object's
gemchain?
...that's the theory, anyway :-) In practice in GEM, things are not
exactly as they may appear...in other words, while I think the
glWrapper is one of GEM's most powerful features, there are a few
decisions made as default behaviors that may cause unexpected
behavior and frustration...fr'instance, glClearColor is called many
times behind your back, such as windowInit, window reset, and the
color message to [gemwin]...
...hmm, now going thru this, you may just want to play with that
message to [gemwin] in conjunction with the clearmask message, which
I think you'll need to send a [GL_COLOR< - [GLdefine] to...? I'll
have to try that out when I have GEM running...
...anyway, as ya can see, there's a bit more to the glWrappers than
just trying an object...it's really important to have a copy of the
"Red Book" on hand, but in general I've found that it's an extremely
quick and powerful way to prototype: no more compiling ;-)
l8r, jamie
Hi James, List
Im not at a machine as we speak that has GEM installed, but ill try
to make the simplest patch to get it working. I appreciate the
feedback about other openGL calls being 'made behind my back' with
regard to the other GEM objects.
Im taking an into to openGL course, learning GLUT, so im programming
with Cocoa/GLUT on OS X, but, then I realized that GEM has wrappers
for the openGL, so I thought id give some stuff a shot.. interesting
that you have to use multiple GEMglWrapper objects together.. you
cannot change certain patch/GEM machine state objects with a
GEMgWrapper object on its own? l
I did use floats between 0,1, and GLDefine and whatnot, but I put the
GEMglClearColor between a gemhead and a rectangle. I *was* able to
change the window background color, but I made no specifications to
GEMglClear(GL_COLOR_BUFFER_BIT) or anything of that nature.
I will play around a bit when I get home and send an example patch,
and maybe someone can point me in the right direction.
...hmm, now going thru this, you may just want to play with that
message to [gemwin] in conjunction with the clearmask message,
which I think you'll need to send a [GL_COLOR< - [GLdefine] to...?
I'll have to try that out when I have GEM running...
I am not familiar with this message, and I dont see it in the
documentation that I have.
thanks!
v a d e //
http://homepage.mac.com/doktorp/ doktorp@mac.com
On Sep 13, 2005, at 11:12 AM, james tittle wrote:
On Sep 13, 2005, at 1:19 AM, vade wrote:
Hello
hiya,
Playing with the gl objects in GEM (0.90) on OS X (Pd 0.38-4
Extended, via Hans) , ive noticed that GEMglClearColor has 5
inputs, one for the gem render chain, 2 - r, 3 - g, 4 - b and
presumably 5 - alpha, yet, changing alpha results in no change in
the window Changing the RGB values does, just like [color] to
gemwin (as it should).Presumably, changing the alpha would act to let the scene draw
'over' itself, and give an easy way to do trails/blurring. Jitter
supports this feature (not griping.. just saying :), any chance ,
or workaround to get similar functionality, as I love the
aesthetic of it. Id rather not use snap2pix/snap2tex....ok, you have the correct inputs to the object, but there are a
coupla things to make sure of:
- the rgba inputs need to be 0-1
- after [GEMglClearColor] you need a [GEMglClear] that clears the
color buffer (GL_COLOR) 3. what is the gemhead ordering? Are you trying to clear
everything via [gemhead 1]? Or are you inserting this into every
drawn object's gemchain?...that's the theory, anyway :-) In practice in GEM, things are
not exactly as they may appear...in other words, while I think the
glWrapper is one of GEM's most powerful features, there are a few
decisions made as default behaviors that may cause unexpected
behavior and frustration...fr'instance, glClearColor is called many
times behind your back, such as windowInit, window reset, and the
color message to [gemwin]......hmm, now going thru this, you may just want to play with that
message to [gemwin] in conjunction with the clearmask message,
which I think you'll need to send a [GL_COLOR< - [GLdefine] to...?
I'll have to try that out when I have GEM running......anyway, as ya can see, there's a bit more to the glWrappers than
just trying an object...it's really important to have a copy of the
"Red Book" on hand, but in general I've found that it's an
extremely quick and powerful way to prototype: no more compiling ;-)l8r, jamie
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