matt:

''no information that the viewer hasn''t already seen''.
that''s not true.. you blend the new frame into it, that''s the new information.

and indeed the ''feedback'' way does not take into account that every timeslice should be weighted in the same way when blending the pictures toghether. but... who will notice? many ppl don''t even notice that their lcd has blur.

and.. the feedback still _blurs_ the motion, so it''s motionblur.
you could have said that it''s not an exact model of the shuttertime artefact (like cbenoi1 said), that would have been correct.

earx

ps sorry for being sucha wise-ass

quote:Original post by Anonymous Poster
matt:

''no information that the viewer hasn''t already seen''.
that''s not true.. you blend the new frame into it, that''s the new information.

Well, obviously the new frame is new information
But that''s no different from not doing any motion blur.

No motion blur:
The viewer has seen the previous frame.
Now they''re going to see the new frame.

Feedback effect:
The viewer has seen the previous frame.
Now they''re going to see the new frame (but with some of the old frame thrown in as well).

No extra information between the 2 techniques

Your other statements sound like a differing opinion on semantics. That''s fine, but I don''t personally agree to call it motion blur.

quote:Original post by Anonymous Poster
and.. the feedback still _blurs_ the motion, so it''s motionblur.

NTSC blends the odd scanlines with the even scanlines of the next frame (interleaving), which ressembles what you are doing here. It softens the picture somewhat, but still it doesn''t leave the continuous trail of a fast-moving object. For this, you need to take many time samples in-between frames; this is not something cheap for real-time gaming apps.

quote:Original post by Dark_Guy
1.) What is motion blur, and how do I create it in DirectX8 ?

Since there are many ways to achieve motionblur-like results, what is it you want to apply it for?

-cb

Well there are a number of issues with your requests.

First and foremost the suggestion you recieved for a "Motion blur" effect on the ship obviously came from someone who did not fully understand what a motion blur is and how it works. A motion blur is usually used to represent massive speed increases in films, you can see this when the starship enterprise goes into "Warp" speed. The ship itself seems to become elongated for a short period of time then once warp is entered the ship Snaps back to it''s origional size & shape. Typically this is how motion bluring works. Trails of the origonal image are left behind and become more transparent the longer they are from the last redraw. So if your ship was moving left to right the right most image would be fully non transparent and the left most image would be fully transparent.

This effect while "cool" for instantanious effects such as the enterprise going into "Warp", or the super hero flash running at high speeds will not look appropriate if used consistantly. You don''t want to leave a motion blur when ever your ship moves left to right up to down unless it''s traveling at "Warp" speed at the current time because it lends itself to become more distracting than anything. Players will need to determine if the motion blured part of the ship is the one being shot at or if the actual ship itself is in danger of being hit by a missle. This will typically frustrate the player.

That said there is another way to accomplish the effect of time based movement with out using a "motion blur". Obviously your ship must have engines to be traveling in space, and those engines have some type of exhaust units. Using a particle system you can create an effect similar which will accomplish the same overall feel as a "motion blur" without the distracting qualities that motionblurs tend to add to game play. Using the particle system you can create a "plasma trail" from your engines which will allow you to show where the ship has traveled from, and give the overall feel that your ship is speeding along at a rapid pase. Longer trails will help make it look as though the ship is moving faster while shorter trails will help make it appear as though the ship is moving slower. http://www.particlesystems.com has alot of information on particle systems that you can look up. That should get you started on the right track.

As for your direct3d programs crashing..Typically direct3d applications don''t "crash" unless you''ve programmed something wrong. You should learn how to use the visual basic debugger to help resolve these problems, and if that doesn''t help perhaps write out a logfile.txt to help you evaluate the problem once the crash happens.

http://freespace.virgin.net/hugo.elias/graphics/x_motion.htm

quote:Original post by _DarkWIng_
switch to opengl so you can use
glEnable( GL_MOTION_BLUR );

(ps: joke)

More likely it''d be an extension - supported by a single vid card maker.

(ps: haha)

Chapel

About the motionblur, one would think you could store
the direction and velocity as a vector in the vertex,
and use a vertexshader to extend and alphablend when needed.
This would probably look somewhat like motionblur, even
if i prefer when videogames looks more "real" than a movie, so
im no fan of motionblur

--
MFC is sorta like the swedish police... It''''s full of crap, and nothing can communicate with anything else.