shadows shadows shadows...

shadows shadows shadows...

Post by DeadHamste » Tue, 18 Feb 2003 08:51:56



I am working on a 3d RTS game for nix and windows. I am currently using
planar shadows for the characters and models, but I would like something a
bit more capable, since planar shadows cant wrap up and down walls and other
models.  I am not sure where to go from here, I have looked at Shadow
Mapping and Shadow Volumes. Is one of these better to use? Shadow volumes
looked easier to do, but seemed to require more attention from the cpu.
Shadow Maps seemed more flexible, but the few demos I saw involved
manipulating the texture matrix, and I couldnt make them work because they
messed up my textures.  I also noticed that the Shadow Mapping demos never
involved any textures.  Is this because you cant use shadow mapping with
textures or because there simply arent any demos?  The lighting is
completely dynamic and will change with every frame, I am also using DOT3
PPL, rendered in hardware.  So if this would effect any of the shadow
techniques, let me know.  I am desperate! Not finishing this part of my code
is making me nuts! Any suggestions would be greatly appreciated!

-DH

 
 
 

shadows shadows shadows...

Post by Kris Garrei » Tue, 18 Feb 2003 16:18:38


Well, shadow mapping is very fast, but the resolution depends on a texture.
Shadow volumes have a resolution conform your meshes, but it needs much more
calculations...

K


Quote:> I am working on a 3d RTS game for nix and windows. I am currently using
> planar shadows for the characters and models, but I would like something a
> bit more capable, since planar shadows cant wrap up and down walls and
other
> models.  I am not sure where to go from here, I have looked at Shadow
> Mapping and Shadow Volumes. Is one of these better to use? Shadow volumes
> looked easier to do, but seemed to require more attention from the cpu.
> Shadow Maps seemed more flexible, but the few demos I saw involved
> manipulating the texture matrix, and I couldnt make them work because they
> messed up my textures.  I also noticed that the Shadow Mapping demos never
> involved any textures.  Is this because you cant use shadow mapping with
> textures or because there simply arent any demos?  The lighting is
> completely dynamic and will change with every frame, I am also using DOT3
> PPL, rendered in hardware.  So if this would effect any of the shadow
> techniques, let me know.  I am desperate! Not finishing this part of my
code
> is making me nuts! Any suggestions would be greatly appreciated!

> -DH


 
 
 

shadows shadows shadows...

Post by DeadHamste » Tue, 18 Feb 2003 20:09:22


Yeah, thats pretty much what I had come up with. The problem is that shadow
volumes are easy to understand, but shadow maps are not. At least not for me
anyway.  I looked at Nvidia's demo for shadow maping, and its a great demo.
But in typical nvidia fashion it has a plethora of features I neither need
or understand, and instead of english its written in nvidia's own
proprietary language (I call it nvidiash).  Any idea where a mere simpleton
can get his hands on a clear-cut demo or tutorial that just has the meat and
potatos? I just cant figure out the nvidia demo, and none of my other
tutorial sites seem to have anything on it.  I also took a look at humus'
demo which was based on an SGI demo, but thats where manipulating the
texture matrix started messing up the skins on my models.

Thanks,
-DH


> Well, shadow mapping is very fast, but the resolution depends on a
texture.
> Shadow volumes have a resolution conform your meshes, but it needs much
more
> calculations...

> K



> > I am working on a 3d RTS game for nix and windows. I am currently using
> > planar shadows for the characters and models, but I would like something
a
> > bit more capable, since planar shadows cant wrap up and down walls and
> other
> > models.  I am not sure where to go from here, I have looked at Shadow
> > Mapping and Shadow Volumes. Is one of these better to use? Shadow
volumes
> > looked easier to do, but seemed to require more attention from the cpu.
> > Shadow Maps seemed more flexible, but the few demos I saw involved
> > manipulating the texture matrix, and I couldnt make them work because
they
> > messed up my textures.  I also noticed that the Shadow Mapping demos
never
> > involved any textures.  Is this because you cant use shadow mapping with
> > textures or because there simply arent any demos?  The lighting is
> > completely dynamic and will change with every frame, I am also using
DOT3
> > PPL, rendered in hardware.  So if this would effect any of the shadow
> > techniques, let me know.  I am desperate! Not finishing this part of my
> code
> > is making me nuts! Any suggestions would be greatly appreciated!

> > -DH

 
 
 

shadows shadows shadows...

Post by Kris Garrei » Tue, 18 Feb 2003 20:13:06


Well, yeah nVidia's demo is kinda over the top :)
You can find a simple shadow volumes demo on my site in the tutorials
section,
and you can find the simplest possible demo on shadow mapping in my thesis
files section.

I think you should check on www.delphi3d.net , there's a better shadow
mapping demo there, which isn't much more difficult than my demo :)
PS: Delphi code is easy to read for a C++ programmer :)

Kris


> Yeah, thats pretty much what I had come up with. The problem is that
shadow
> volumes are easy to understand, but shadow maps are not. At least not for
me
> anyway.  I looked at Nvidia's demo for shadow maping, and its a great
demo.
> But in typical nvidia fashion it has a plethora of features I neither need
> or understand, and instead of english its written in nvidia's own
> proprietary language (I call it nvidiash).  Any idea where a mere
simpleton
> can get his hands on a clear-cut demo or tutorial that just has the meat
and
> potatos? I just cant figure out the nvidia demo, and none of my other
> tutorial sites seem to have anything on it.  I also took a look at humus'
> demo which was based on an SGI demo, but thats where manipulating the
> texture matrix started messing up the skins on my models.

> Thanks,
> -DH



> > Well, shadow mapping is very fast, but the resolution depends on a
> texture.
> > Shadow volumes have a resolution conform your meshes, but it needs much
> more
> > calculations...

> > K



> > > I am working on a 3d RTS game for nix and windows. I am currently
using
> > > planar shadows for the characters and models, but I would like
something
> a
> > > bit more capable, since planar shadows cant wrap up and down walls and
> > other
> > > models.  I am not sure where to go from here, I have looked at Shadow
> > > Mapping and Shadow Volumes. Is one of these better to use? Shadow
> volumes
> > > looked easier to do, but seemed to require more attention from the
cpu.
> > > Shadow Maps seemed more flexible, but the few demos I saw involved
> > > manipulating the texture matrix, and I couldnt make them work because
> they
> > > messed up my textures.  I also noticed that the Shadow Mapping demos
> never
> > > involved any textures.  Is this because you cant use shadow mapping
with
> > > textures or because there simply arent any demos?  The lighting is
> > > completely dynamic and will change with every frame, I am also using
> DOT3
> > > PPL, rendered in hardware.  So if this would effect any of the shadow
> > > techniques, let me know.  I am desperate! Not finishing this part of
my
> > code
> > > is making me nuts! Any suggestions would be greatly appreciated!

> > > -DH

 
 
 

shadows shadows shadows...

Post by Kris Garrei » Tue, 18 Feb 2003 20:16:18


oops, my website: http://www.blue-print.be.tf

Kris


> Well, yeah nVidia's demo is kinda over the top :)
> You can find a simple shadow volumes demo on my site in the tutorials
> section,
> and you can find the simplest possible demo on shadow mapping in my thesis
> files section.

> I think you should check on www.delphi3d.net , there's a better shadow
> mapping demo there, which isn't much more difficult than my demo :)
> PS: Delphi code is easy to read for a C++ programmer :)

> Kris



> > Yeah, thats pretty much what I had come up with. The problem is that
> shadow
> > volumes are easy to understand, but shadow maps are not. At least not
for
> me
> > anyway.  I looked at Nvidia's demo for shadow maping, and its a great
> demo.
> > But in typical nvidia fashion it has a plethora of features I neither
need
> > or understand, and instead of english its written in nvidia's own
> > proprietary language (I call it nvidiash).  Any idea where a mere
> simpleton
> > can get his hands on a clear-cut demo or tutorial that just has the meat
> and
> > potatos? I just cant figure out the nvidia demo, and none of my other
> > tutorial sites seem to have anything on it.  I also took a look at
humus'
> > demo which was based on an SGI demo, but thats where manipulating the
> > texture matrix started messing up the skins on my models.

> > Thanks,
> > -DH



> > > Well, shadow mapping is very fast, but the resolution depends on a
> > texture.
> > > Shadow volumes have a resolution conform your meshes, but it needs
much
> > more
> > > calculations...

> > > K



> > > > I am working on a 3d RTS game for nix and windows. I am currently
> using
> > > > planar shadows for the characters and models, but I would like
> something
> > a
> > > > bit more capable, since planar shadows cant wrap up and down walls
and
> > > other
> > > > models.  I am not sure where to go from here, I have looked at
Shadow
> > > > Mapping and Shadow Volumes. Is one of these better to use? Shadow
> > volumes
> > > > looked easier to do, but seemed to require more attention from the
> cpu.
> > > > Shadow Maps seemed more flexible, but the few demos I saw involved
> > > > manipulating the texture matrix, and I couldnt make them work
because
> > they
> > > > messed up my textures.  I also noticed that the Shadow Mapping demos
> > never
> > > > involved any textures.  Is this because you cant use shadow mapping
> with
> > > > textures or because there simply arent any demos?  The lighting is
> > > > completely dynamic and will change with every frame, I am also using
> > DOT3
> > > > PPL, rendered in hardware.  So if this would effect any of the
shadow
> > > > techniques, let me know.  I am desperate! Not finishing this part of
> my
> > > code
> > > > is making me nuts! Any suggestions would be greatly appreciated!

> > > > -DH

 
 
 

shadows shadows shadows...

Post by DeadHamste » Tue, 18 Feb 2003 21:00:10


aahh cool, thank ya. I have looked at your site before, lots of good stuff
there.  In fact I made an error in my previous posts.  It was your shadow
mapping demo I looked at after I got off the floor from when nvidia's made
me pass out ;)

Since you are the man here, maybe you can help me then :)

My problem when I tried your demo was that because of the changes to the
texture matrix, any textures involved in my scene would get messed up.
Admittedly my understanding is weak, which is why I am about to read your
thesis in hopes of giving me a good understanding of the theory.  Have you
tried your method on a more complicated scene involving textures?  I
understand what I am doing as far as creating the depth texture goes, but
its implementing it that baffles me.  I am not adverse to reading, so if you
can reccomend a good book I would be more than happy to give it a look.

Thanks, and keep up the good work!
-DH


> oops, my website: http://www.blue-print.be.tf

> Kris



> > Well, yeah nVidia's demo is kinda over the top :)
> > You can find a simple shadow volumes demo on my site in the tutorials
> > section,
> > and you can find the simplest possible demo on shadow mapping in my
thesis
> > files section.

> > I think you should check on www.delphi3d.net , there's a better shadow
> > mapping demo there, which isn't much more difficult than my demo :)
> > PS: Delphi code is easy to read for a C++ programmer :)

> > Kris



> > > Yeah, thats pretty much what I had come up with. The problem is that
> > shadow
> > > volumes are easy to understand, but shadow maps are not. At least not
> for
> > me
> > > anyway.  I looked at Nvidia's demo for shadow maping, and its a great
> > demo.
> > > But in typical nvidia fashion it has a plethora of features I neither
> need
> > > or understand, and instead of english its written in nvidia's own
> > > proprietary language (I call it nvidiash).  Any idea where a mere
> > simpleton
> > > can get his hands on a clear-cut demo or tutorial that just has the
meat
> > and
> > > potatos? I just cant figure out the nvidia demo, and none of my other
> > > tutorial sites seem to have anything on it.  I also took a look at
> humus'
> > > demo which was based on an SGI demo, but thats where manipulating the
> > > texture matrix started messing up the skins on my models.

> > > Thanks,
> > > -DH



> > > > Well, shadow mapping is very fast, but the resolution depends on a
> > > texture.
> > > > Shadow volumes have a resolution conform your meshes, but it needs
> much
> > > more
> > > > calculations...

> > > > K



> > > > > I am working on a 3d RTS game for nix and windows. I am currently
> > using
> > > > > planar shadows for the characters and models, but I would like
> > something
> > > a
> > > > > bit more capable, since planar shadows cant wrap up and down walls
> and
> > > > other
> > > > > models.  I am not sure where to go from here, I have looked at
> Shadow
> > > > > Mapping and Shadow Volumes. Is one of these better to use? Shadow
> > > volumes
> > > > > looked easier to do, but seemed to require more attention from the
> > cpu.
> > > > > Shadow Maps seemed more flexible, but the few demos I saw involved
> > > > > manipulating the texture matrix, and I couldnt make them work
> because
> > > they
> > > > > messed up my textures.  I also noticed that the Shadow Mapping
demos
> > > never
> > > > > involved any textures.  Is this because you cant use shadow
mapping
> > with
> > > > > textures or because there simply arent any demos?  The lighting is
> > > > > completely dynamic and will change with every frame, I am also
using
> > > DOT3
> > > > > PPL, rendered in hardware.  So if this would effect any of the
> shadow
> > > > > techniques, let me know.  I am desperate! Not finishing this part
of
> > my
> > > > code
> > > > > is making me nuts! Any suggestions would be greatly appreciated!

> > > > > -DH

 
 
 

shadows shadows shadows...

Post by Kris Garrei » Tue, 18 Feb 2003 21:55:45


Actually, my shadow mapping demo isn't that good :)
The one you can find on delphi3d has much better mapping and resolution...
I learned how to do it (like in my demo) from the SGI website, a good search
and you will find the examples there...

Basicly you render to a depth texture, and depending on that depth texture,
scene objects will be rendered with or without shadow...

Kris


> aahh cool, thank ya. I have looked at your site before, lots of good stuff
> there.  In fact I made an error in my previous posts.  It was your shadow
> mapping demo I looked at after I got off the floor from when nvidia's made
> me pass out ;)

> Since you are the man here, maybe you can help me then :)

> My problem when I tried your demo was that because of the changes to the
> texture matrix, any textures involved in my scene would get messed up.
> Admittedly my understanding is weak, which is why I am about to read your
> thesis in hopes of giving me a good understanding of the theory.  Have you
> tried your method on a more complicated scene involving textures?  I
> understand what I am doing as far as creating the depth texture goes, but
> its implementing it that baffles me.  I am not adverse to reading, so if
you
> can reccomend a good book I would be more than happy to give it a look.

> Thanks, and keep up the good work!
> -DH



> > oops, my website: http://www.blue-print.be.tf

> > Kris



> > > Well, yeah nVidia's demo is kinda over the top :)
> > > You can find a simple shadow volumes demo on my site in the tutorials
> > > section,
> > > and you can find the simplest possible demo on shadow mapping in my
> thesis
> > > files section.

> > > I think you should check on www.delphi3d.net , there's a better shadow
> > > mapping demo there, which isn't much more difficult than my demo :)
> > > PS: Delphi code is easy to read for a C++ programmer :)

> > > Kris



> > > > Yeah, thats pretty much what I had come up with. The problem is that
> > > shadow
> > > > volumes are easy to understand, but shadow maps are not. At least
not
> > for
> > > me
> > > > anyway.  I looked at Nvidia's demo for shadow maping, and its a
great
> > > demo.
> > > > But in typical nvidia fashion it has a plethora of features I
neither
> > need
> > > > or understand, and instead of english its written in nvidia's own
> > > > proprietary language (I call it nvidiash).  Any idea where a mere
> > > simpleton
> > > > can get his hands on a clear-cut demo or tutorial that just has the
> meat
> > > and
> > > > potatos? I just cant figure out the nvidia demo, and none of my
other
> > > > tutorial sites seem to have anything on it.  I also took a look at
> > humus'
> > > > demo which was based on an SGI demo, but thats where manipulating
the
> > > > texture matrix started messing up the skins on my models.

> > > > Thanks,
> > > > -DH



> > > > > Well, shadow mapping is very fast, but the resolution depends on a
> > > > texture.
> > > > > Shadow volumes have a resolution conform your meshes, but it needs
> > much
> > > > more
> > > > > calculations...

> > > > > K



> > > > > > I am working on a 3d RTS game for nix and windows. I am
currently
> > > using
> > > > > > planar shadows for the characters and models, but I would like
> > > something
> > > > a
> > > > > > bit more capable, since planar shadows cant wrap up and down
walls
> > and
> > > > > other
> > > > > > models.  I am not sure where to go from here, I have looked at
> > Shadow
> > > > > > Mapping and Shadow Volumes. Is one of these better to use?
Shadow
> > > > volumes
> > > > > > looked easier to do, but seemed to require more attention from
the
> > > cpu.
> > > > > > Shadow Maps seemed more flexible, but the few demos I saw
involved
> > > > > > manipulating the texture matrix, and I couldnt make them work
> > because
> > > > they
> > > > > > messed up my textures.  I also noticed that the Shadow Mapping
> demos
> > > > never
> > > > > > involved any textures.  Is this because you cant use shadow
> mapping
> > > with
> > > > > > textures or because there simply arent any demos?  The lighting
is
> > > > > > completely dynamic and will change with every frame, I am also
> using
> > > > DOT3
> > > > > > PPL, rendered in hardware.  So if this would effect any of the
> > shadow
> > > > > > techniques, let me know.  I am desperate! Not finishing this
part
> of
> > > my
> > > > > code
> > > > > > is making me nuts! Any suggestions would be greatly appreciated!

> > > > > > -DH

 
 
 

shadows shadows shadows...

Post by zed » Wed, 19 Feb 2003 04:56:25



> Is one of these better to use? Shadow volumes
> looked easier to do, but seemed to require more attention from the cpu.
> Shadow Maps seemed more flexible, but the few demos I saw involved
> manipulating the texture matrix, and I couldnt make them work because they
> messed up my textures.  I also noticed that the Shadow Mapping demos never
> involved any textures.  Is this because you cant use shadow mapping with
> textures or because there simply arent any demos?  The lighting is
> completely dynamic and will change with every frame, I am also using DOT3
> PPL, rendered in hardware.  So if this would effect any of the shadow
> techniques, let me know.  I am desperate! Not finishing this part of my code
> is making me nuts! Any suggestions would be greatly appreciated!

ild say shadowmaps are easier to do!

shadowmaps -
for
* scales well
* handles transparency
* part of opengl1.4
against
* expensive (esp point lights)
* not supported on most hardwre eg gf3 supports it but gf2 doesnt

shadowvolumes -
for
* doom3 uses them
* able to run on most machines
against
* scales terribly
* not very futureproof
* requires mesh fudging

i prefer shadowmaps (i believe most cg films use this method) there
major problem is not many cards support them

--
lets hear it for billy bollux and his bouncing balls
http://uk.geocities.com/sloppyturds/kea/kea.html

 
 
 

shadows shadows shadows...

Post by DeadHamste » Wed, 19 Feb 2003 08:53:41


I think I would have to agree. The more I look at the two methods the more I
am liking shadow maps. I consider shadows an optional feature anyway so I
dont mind limiting them to people with a gf3 or better card.  Though I have
to admit, from a programming standpoint I would really rather be using
shadow volumes :P

-DH



> > Is one of these better to use? Shadow volumes
> > looked easier to do, but seemed to require more attention from the cpu.
> > Shadow Maps seemed more flexible, but the few demos I saw involved
> > manipulating the texture matrix, and I couldnt make them work because
they
> > messed up my textures.  I also noticed that the Shadow Mapping demos
never
> > involved any textures.  Is this because you cant use shadow mapping with
> > textures or because there simply arent any demos?  The lighting is
> > completely dynamic and will change with every frame, I am also using
DOT3
> > PPL, rendered in hardware.  So if this would effect any of the shadow
> > techniques, let me know.  I am desperate! Not finishing this part of my
code
> > is making me nuts! Any suggestions would be greatly appreciated!

> ild say shadowmaps are easier to do!

> shadowmaps -
> for
> * scales well
> * handles transparency
> * part of opengl1.4
> against
> * expensive (esp point lights)
> * not supported on most hardwre eg gf3 supports it but gf2 doesnt

> shadowvolumes -
> for
> * doom3 uses them
> * able to run on most machines
> against
> * scales terribly
> * not very futureproof
> * requires mesh fudging

> i prefer shadowmaps (i believe most cg films use this method) there
> major problem is not many cards support them

> --
> lets hear it for billy bollux and his bouncing balls
> http://uk.geocities.com/sloppyturds/kea/kea.html

 
 
 

shadows shadows shadows...

Post by DeadHamste » Wed, 19 Feb 2003 09:42:29


Ok, I have given the delphi3d demo a look.  My scene did not change at all
when I added the depth mapping code, and it made me wonder about something.
I am currently using TEXTURE0 for bump maps, and TEXTURE1 for my textures.
So naturally, I just used TEXTURE2 for my depth map.  Is it important that I
used TEXTURE0 for the depth map or can I use whichever unit I like?  I am
sure my questions are newbish to you, but thats probably because I am a
newby :)

-DH


> Actually, my shadow mapping demo isn't that good :)
> The one you can find on delphi3d has much better mapping and resolution...
> I learned how to do it (like in my demo) from the SGI website, a good
search
> and you will find the examples there...

> Basicly you render to a depth texture, and depending on that depth
texture,
> scene objects will be rendered with or without shadow...

> Kris



> > aahh cool, thank ya. I have looked at your site before, lots of good
stuff
> > there.  In fact I made an error in my previous posts.  It was your
shadow
> > mapping demo I looked at after I got off the floor from when nvidia's
made
> > me pass out ;)

> > Since you are the man here, maybe you can help me then :)

> > My problem when I tried your demo was that because of the changes to the
> > texture matrix, any textures involved in my scene would get messed up.
> > Admittedly my understanding is weak, which is why I am about to read
your
> > thesis in hopes of giving me a good understanding of the theory.  Have
you
> > tried your method on a more complicated scene involving textures?  I
> > understand what I am doing as far as creating the depth texture goes,
but
> > its implementing it that baffles me.  I am not adverse to reading, so if
> you
> > can reccomend a good book I would be more than happy to give it a look.

> > Thanks, and keep up the good work!
> > -DH



> > > oops, my website: http://www.blue-print.be.tf

> > > Kris



> > > > Well, yeah nVidia's demo is kinda over the top :)
> > > > You can find a simple shadow volumes demo on my site in the
tutorials
> > > > section,
> > > > and you can find the simplest possible demo on shadow mapping in my
> > thesis
> > > > files section.

> > > > I think you should check on www.delphi3d.net , there's a better
shadow
> > > > mapping demo there, which isn't much more difficult than my demo :)
> > > > PS: Delphi code is easy to read for a C++ programmer :)

> > > > Kris



> > > > > Yeah, thats pretty much what I had come up with. The problem is
that
> > > > shadow
> > > > > volumes are easy to understand, but shadow maps are not. At least
> not
> > > for
> > > > me
> > > > > anyway.  I looked at Nvidia's demo for shadow maping, and its a
> great
> > > > demo.
> > > > > But in typical nvidia fashion it has a plethora of features I
> neither
> > > need
> > > > > or understand, and instead of english its written in nvidia's own
> > > > > proprietary language (I call it nvidiash).  Any idea where a mere
> > > > simpleton
> > > > > can get his hands on a clear-cut demo or tutorial that just has
the
> > meat
> > > > and
> > > > > potatos? I just cant figure out the nvidia demo, and none of my
> other
> > > > > tutorial sites seem to have anything on it.  I also took a look at
> > > humus'
> > > > > demo which was based on an SGI demo, but thats where manipulating
> the
> > > > > texture matrix started messing up the skins on my models.

> > > > > Thanks,
> > > > > -DH



> > > > > > Well, shadow mapping is very fast, but the resolution depends on
a
> > > > > texture.
> > > > > > Shadow volumes have a resolution conform your meshes, but it
needs
> > > much
> > > > > more
> > > > > > calculations...

> > > > > > K



> > > > > > > I am working on a 3d RTS game for nix and windows. I am
> currently
> > > > using
> > > > > > > planar shadows for the characters and models, but I would like
> > > > something
> > > > > a
> > > > > > > bit more capable, since planar shadows cant wrap up and down
> walls
> > > and
> > > > > > other
> > > > > > > models.  I am not sure where to go from here, I have looked at
> > > Shadow
> > > > > > > Mapping and Shadow Volumes. Is one of these better to use?
> Shadow
> > > > > volumes
> > > > > > > looked easier to do, but seemed to require more attention from
> the
> > > > cpu.
> > > > > > > Shadow Maps seemed more flexible, but the few demos I saw
> involved
> > > > > > > manipulating the texture matrix, and I couldnt make them work
> > > because
> > > > > they
> > > > > > > messed up my textures.  I also noticed that the Shadow Mapping
> > demos
> > > > > never
> > > > > > > involved any textures.  Is this because you cant use shadow
> > mapping
> > > > with
> > > > > > > textures or because there simply arent any demos?  The
lighting
> is
> > > > > > > completely dynamic and will change with every frame, I am also
> > using
> > > > > DOT3
> > > > > > > PPL, rendered in hardware.  So if this would effect any of the
> > > shadow
> > > > > > > techniques, let me know.  I am desperate! Not finishing this
> part
> > of
> > > > my
> > > > > > code
> > > > > > > is making me nuts! Any suggestions would be greatly
appreciated!

> > > > > > > -DH

 
 
 

shadows shadows shadows...

Post by Kris Garrei » Wed, 19 Feb 2003 17:56:08


I will be honest here :)
After doing that thesis I've started a job(bills need to get paid) that's
not GL-related, I haven't had the time to do anything decent using opengl
since :(
I've used multitexturing before, but I never even tried using shadow mapping
together with multitexturing... In some ways I think I'm more a noob to
opengl than you...

%Kris


> Ok, I have given the delphi3d demo a look.  My scene did not change at all
> when I added the depth mapping code, and it made me wonder about
something.
> I am currently using TEXTURE0 for bump maps, and TEXTURE1 for my textures.
> So naturally, I just used TEXTURE2 for my depth map.  Is it important that
I
> used TEXTURE0 for the depth map or can I use whichever unit I like?  I am
> sure my questions are newbish to you, but thats probably because I am a
> newby :)

> -DH



> > Actually, my shadow mapping demo isn't that good :)
> > The one you can find on delphi3d has much better mapping and
resolution...
> > I learned how to do it (like in my demo) from the SGI website, a good
> search
> > and you will find the examples there...

> > Basicly you render to a depth texture, and depending on that depth
> texture,
> > scene objects will be rendered with or without shadow...

> > Kris



> > > aahh cool, thank ya. I have looked at your site before, lots of good
> stuff
> > > there.  In fact I made an error in my previous posts.  It was your
> shadow
> > > mapping demo I looked at after I got off the floor from when nvidia's
> made
> > > me pass out ;)

> > > Since you are the man here, maybe you can help me then :)

> > > My problem when I tried your demo was that because of the changes to
the
> > > texture matrix, any textures involved in my scene would get messed up.
> > > Admittedly my understanding is weak, which is why I am about to read
> your
> > > thesis in hopes of giving me a good understanding of the theory.  Have
> you
> > > tried your method on a more complicated scene involving textures?  I
> > > understand what I am doing as far as creating the depth texture goes,
> but
> > > its implementing it that baffles me.  I am not adverse to reading, so
if
> > you
> > > can reccomend a good book I would be more than happy to give it a
look.

> > > Thanks, and keep up the good work!
> > > -DH



> > > > oops, my website: http://www.blue-print.be.tf

> > > > Kris



> > > > > Well, yeah nVidia's demo is kinda over the top :)
> > > > > You can find a simple shadow volumes demo on my site in the
> tutorials
> > > > > section,
> > > > > and you can find the simplest possible demo on shadow mapping in
my
> > > thesis
> > > > > files section.

> > > > > I think you should check on www.delphi3d.net , there's a better
> shadow
> > > > > mapping demo there, which isn't much more difficult than my demo
:)
> > > > > PS: Delphi code is easy to read for a C++ programmer :)

> > > > > Kris



> > > > > > Yeah, thats pretty much what I had come up with. The problem is
> that
> > > > > shadow
> > > > > > volumes are easy to understand, but shadow maps are not. At
least
> > not
> > > > for
> > > > > me
> > > > > > anyway.  I looked at Nvidia's demo for shadow maping, and its a
> > great
> > > > > demo.
> > > > > > But in typical nvidia fashion it has a plethora of features I
> > neither
> > > > need
> > > > > > or understand, and instead of english its written in nvidia's
own
> > > > > > proprietary language (I call it nvidiash).  Any idea where a
mere
> > > > > simpleton
> > > > > > can get his hands on a clear-cut demo or tutorial that just has
> the
> > > meat
> > > > > and
> > > > > > potatos? I just cant figure out the nvidia demo, and none of my
> > other
> > > > > > tutorial sites seem to have anything on it.  I also took a look
at
> > > > humus'
> > > > > > demo which was based on an SGI demo, but thats where
manipulating
> > the
> > > > > > texture matrix started messing up the skins on my models.

> > > > > > Thanks,
> > > > > > -DH



> > > > > > > Well, shadow mapping is very fast, but the resolution depends
on
> a
> > > > > > texture.
> > > > > > > Shadow volumes have a resolution conform your meshes, but it
> needs
> > > > much
> > > > > > more
> > > > > > > calculations...

> > > > > > > K



> > > > > > > > I am working on a 3d RTS game for nix and windows. I am
> > currently
> > > > > using
> > > > > > > > planar shadows for the characters and models, but I would
like
> > > > > something
> > > > > > a
> > > > > > > > bit more capable, since planar shadows cant wrap up and down
> > walls
> > > > and
> > > > > > > other
> > > > > > > > models.  I am not sure where to go from here, I have looked
at
> > > > Shadow
> > > > > > > > Mapping and Shadow Volumes. Is one of these better to use?
> > Shadow
> > > > > > volumes
> > > > > > > > looked easier to do, but seemed to require more attention
from
> > the
> > > > > cpu.
> > > > > > > > Shadow Maps seemed more flexible, but the few demos I saw
> > involved
> > > > > > > > manipulating the texture matrix, and I couldnt make them
work
> > > > because
> > > > > > they
> > > > > > > > messed up my textures.  I also noticed that the Shadow
Mapping
> > > demos
> > > > > > never
> > > > > > > > involved any textures.  Is this because you cant use shadow
> > > mapping
> > > > > with
> > > > > > > > textures or because there simply arent any demos?  The
> lighting
> > is
> > > > > > > > completely dynamic and will change with every frame, I am
also
> > > using
> > > > > > DOT3
> > > > > > > > PPL, rendered in hardware.  So if this would effect any of
the
> > > > shadow
> > > > > > > > techniques, let me know.  I am desperate! Not finishing this
> > part
> > > of
> > > > > my
> > > > > > > code
> > > > > > > > is making me nuts! Any suggestions would be greatly
> appreciated!

> > > > > > > > -DH

 
 
 

shadows shadows shadows...

Post by DeadHamste » Wed, 19 Feb 2003 18:03:09


No problem, I will get it all sorted out eventually. That delphi3d demo got
me closer than I have been before.  Thanks for the info.  I actually have it
nearly working I think.  Instead of projecting the shadow, its projecting a
texture of the whole scene. Its wrong, but looks kinda funny. hehe

-DH

"Kris Garrein" <valheru...@hotmail.com> wrote in message

news:Iym4a.58655$Jd.6794@afrodite.telenet-ops.be...
> I will be honest here :)
> After doing that thesis I've started a job(bills need to get paid) that's
> not GL-related, I haven't had the time to do anything decent using opengl
> since :(
> I've used multitexturing before, but I never even tried using shadow
mapping
> together with multitexturing... In some ways I think I'm more a noob to
> opengl than you...

> %Kris

> "DeadHamster" <fakeemaila...@ihatespam.com> wrote in message
> news:Vjf4a.40846$Rx3.1437792@news1.west.cox.net...
> > Ok, I have given the delphi3d demo a look.  My scene did not change at
all
> > when I added the depth mapping code, and it made me wonder about
> something.
> > I am currently using TEXTURE0 for bump maps, and TEXTURE1 for my
textures.
> > So naturally, I just used TEXTURE2 for my depth map.  Is it important
that
> I
> > used TEXTURE0 for the depth map or can I use whichever unit I like?  I
am
> > sure my questions are newbish to you, but thats probably because I am a
> > newby :)

> > -DH

> > "Kris Garrein" <valheru...@hotmail.com> wrote in message
> > news:lZ44a.56896$Jd.6361@afrodite.telenet-ops.be...
> > > Actually, my shadow mapping demo isn't that good :)
> > > The one you can find on delphi3d has much better mapping and
> resolution...
> > > I learned how to do it (like in my demo) from the SGI website, a good
> > search
> > > and you will find the examples there...

> > > Basicly you render to a depth texture, and depending on that depth
> > texture,
> > > scene objects will be rendered with or without shadow...

> > > Kris

> > > "DeadHamster" <fakeemaila...@ihatespam.com> wrote in message
> > > news:e944a.33836$Rx3.1218666@news1.west.cox.net...
> > > > aahh cool, thank ya. I have looked at your site before, lots of good
> > stuff
> > > > there.  In fact I made an error in my previous posts.  It was your
> > shadow
> > > > mapping demo I looked at after I got off the floor from when
nvidia's
> > made
> > > > me pass out ;)

> > > > Since you are the man here, maybe you can help me then :)

> > > > My problem when I tried your demo was that because of the changes to
> the
> > > > texture matrix, any textures involved in my scene would get messed
up.
> > > > Admittedly my understanding is weak, which is why I am about to read
> > your
> > > > thesis in hopes of giving me a good understanding of the theory.
Have
> > you
> > > > tried your method on a more complicated scene involving textures?  I
> > > > understand what I am doing as far as creating the depth texture
goes,
> > but
> > > > its implementing it that baffles me.  I am not adverse to reading,
so
> if
> > > you
> > > > can reccomend a good book I would be more than happy to give it a
> look.

> > > > Thanks, and keep up the good work!
> > > > -DH

> > > > "Kris Garrein" <valheru...@hotmail.com> wrote in message
> > > > news:6w34a.56785$Jd.6436@afrodite.telenet-ops.be...
> > > > > oops, my website: http://www.blue-print.be.tf

> > > > > Kris

> > > > > "Kris Garrein" <valheru...@hotmail.com> wrote in message
> > > > > news:6t34a.56779$Jd.6550@afrodite.telenet-ops.be...
> > > > > > Well, yeah nVidia's demo is kinda over the top :)
> > > > > > You can find a simple shadow volumes demo on my site in the
> > tutorials
> > > > > > section,
> > > > > > and you can find the simplest possible demo on shadow mapping in
> my
> > > > thesis
> > > > > > files section.

> > > > > > I think you should check on www.delphi3d.net , there's a better
> > shadow
> > > > > > mapping demo there, which isn't much more difficult than my demo
> :)
> > > > > > PS: Delphi code is easy to read for a C++ programmer :)

> > > > > > Kris

> > > > > > "DeadHamster" <fakeemaila...@ihatespam.com> wrote in message
> > > > > > news:Cp34a.33831$Rx3.1249094@news1.west.cox.net...
> > > > > > > Yeah, thats pretty much what I had come up with. The problem
is
> > that
> > > > > > shadow
> > > > > > > volumes are easy to understand, but shadow maps are not. At
> least
> > > not
> > > > > for
> > > > > > me
> > > > > > > anyway.  I looked at Nvidia's demo for shadow maping, and its
a
> > > great
> > > > > > demo.
> > > > > > > But in typical nvidia fashion it has a plethora of features I
> > > neither
> > > > > need
> > > > > > > or understand, and instead of english its written in nvidia's
> own
> > > > > > > proprietary language (I call it nvidiash).  Any idea where a
> mere
> > > > > > simpleton
> > > > > > > can get his hands on a clear-cut demo or tutorial that just
has
> > the
> > > > meat
> > > > > > and
> > > > > > > potatos? I just cant figure out the nvidia demo, and none of
my
> > > other
> > > > > > > tutorial sites seem to have anything on it.  I also took a
look
> at
> > > > > humus'
> > > > > > > demo which was based on an SGI demo, but thats where
> manipulating
> > > the
> > > > > > > texture matrix started messing up the skins on my models.

> > > > > > > Thanks,
> > > > > > > -DH

> > > > > > > "Kris Garrein" <valheru...@hotmail.com> wrote in message
> > > > > > > news:i104a.56558$Jd.6500@afrodite.telenet-ops.be...
> > > > > > > > Well, shadow mapping is very fast, but the resolution
depends
> on
> > a
> > > > > > > texture.
> > > > > > > > Shadow volumes have a resolution conform your meshes, but it
> > needs
> > > > > much
> > > > > > > more
> > > > > > > > calculations...

> > > > > > > > K

> > > > > > > > "DeadHamster" <fakeemaila...@ihatespam.com> wrote in message
> > > > > > > > news:wuV3a.31962$Rx3.1056234@news1.west.cox.net...
> > > > > > > > > I am working on a 3d RTS game for nix and windows. I am
> > > currently
> > > > > > using
> > > > > > > > > planar shadows for the characters and models, but I would
> like
> > > > > > something
> > > > > > > a
> > > > > > > > > bit more capable, since planar shadows cant wrap up and
down
> > > walls
> > > > > and
> > > > > > > > other
> > > > > > > > > models.  I am not sure where to go from here, I have
looked
> at
> > > > > Shadow
> > > > > > > > > Mapping and Shadow Volumes. Is one of these better to use?
> > > Shadow
> > > > > > > volumes
> > > > > > > > > looked easier to do, but seemed to require more attention
> from
> > > the
> > > > > > cpu.
> > > > > > > > > Shadow Maps seemed more flexible, but the few demos I saw
> > > involved
> > > > > > > > > manipulating the texture matrix, and I couldnt make them
> work
> > > > > because
> > > > > > > they
> > > > > > > > > messed up my textures.  I also noticed that the Shadow
> Mapping
> > > > demos
> > > > > > > never
> > > > > > > > > involved any textures.  Is this because you cant use
shadow
> > > > mapping
> > > > > > with
> > > > > > > > > textures or because there simply arent any demos?  The
> > lighting
> > > is
> > > > > > > > > completely dynamic and will change with every frame, I am
> also
> > > > using
> > > > > > > DOT3
> > > > > > > > > PPL, rendered in hardware.  So if this would effect any of
> the
> > > > > shadow
> > > > > > > > > techniques, let me know.  I am desperate! Not finishing
this
> > > part
> > > > of
> > > > > > my
> > > > > > > > code
> > > > > > > > > is making me nuts! Any suggestions would be greatly
> > appreciated!

> > > > > > > > > -DH

 
 
 

1. Shadow maps and soft shadows

Hello everybody,

I'm trying to understand how the renderers use shadow maps to produce soft
shadows. I understand how a "simple shadow map algorithm" works (i.e.
compare a surface point's distance to the light against the value stored in
the shadow map) and the associated aliasing problem. I've read Reeves'
Siggraph '87 paper and can see how sampling an area in the shadow map helps
with the aliasing problem and creates a little bit of "softness". However,
just sampling an area of the shadow map sounds like a big fudge to me and
like something that wouldn't work in all situations. Can anybody explain to
me how it is actually done inside the renderers?

Thanks in advance,
Rune

2. *.dem to *.3ds

3. Shadow quality vs shadow ray visibility

4. Converting *.cdr to *.ai

5. - shadow.jpeg (0/2) shadow.jpeg

6. Polyon-mesh mapping algorithm

7. - shadow.jpeg (2/2) shadow.jpeg

8. call win32 api function from glut app

9. - shadow.jpeg (1/2) shadow.jpeg

10. Ray traced shadows create false shadow

11. Hypervoxels dont cast shadows with shadow mapped spot

12. Gaffer shadows vs area light shadows

13. Self-shadowing problems with shadow maps