Bump mapping is a way of representing high frequency geometrical detail on a low frequency approximation. It has a few disadvantages, (depending on how you do it) - try looking at a bump mapped surface side on, and you'll see nothing but flatness.
This doesn't really have much impact on modelling cloth.
Incidentally, the effect you mention in Unreal is called detail texturing, which involves modulating the source texture with a high resolution, but smaller texture at proximity.
Of course we can't do realistic real-time cloth...
on
Simulating Cloth in CG
·
· Score: 2
Computer graphics is an exercise in modelling.
Practically every technique that is in use in graphics today (specifically, and particularly, in games), is a model, an approximation to the real world. Texture mapping, polygonal approximation, simplistic lighting models - all of these are convenient, efficient, and realistic looking models of real life.
What the story appears to say is "computers are far away from this particular model". Well, that's always going to be true, since the model can always get more realistic and detailed, up until the limits of understanding particle interaction in modern physics.
The presentation itself is very interesting, and also presents some models that are somewhat feasible for limited use in today's applications.
Microsoft have been very keen to show that the CLR is not tied to just one development language. They have guys working on, for instance, and ;Co bol(!) implementations, which seem to be a proof-of-concept demonstration of the independance of the CLR. While, as the article is at pains to point out, the basic concepts aren't new (although what in computer science is?), it seems to me that the.NET framework represents a interesting and new set of ideas to work with. Bear in mind, as another poster pointed out, that there is no reason the.NET framework cannot be ported. But even if not, it seems a little unreasonable for to lambast microsoft for producing something as obviously fully developed as this.
Admittedly, using propietory keywords in C++ is a horrible thing to do.
Not 3dlabs fault. I can't remember who originally coined the term, but it's been around for a while. A voxel is a volume pixel (pixel = picture element), and thus has width, height and depth. They were used in Command & Conquer: Tiberian Sun (although I don't know whether they were preprocessed down to sprites).
switching to another modelling paradigm is not just a case of 'ooh it goes fast!'. The use of polygons is so ingrained in computer graphics today that to move to another primitive would involve a lot of effort.
AFAIK, artist's 3d tools are geared towards polygonal based rendering. It's not a given that artists will find voxels intuitive to model with (although it may be that the raster-vector analogy stands). I'm not an artist so I don't know. But one of the challenges will be providing decent tools.
More significantly, many of the fundemental problems in computer graphics, such as visibility and lighting, have been solved in efficient ways for polygons in particular. I'm not greatly familiar with the current state of affairs in voxel based research, but there's a lot of basic techniques that are used today in polygonal-based rendering aside from drawing filled spans that may not translate directly to a new paradigm.
Perhaps the fact that the accelerator is a hybrid is key, since the different representations can be applied to more suitable constructions. But I think there's a way to go before voxels become mainstream, simply because they don't translate directly to polygons, and hence the class of problems associated with primitive rendering is not already solved.
is this incorporated with Glade. While one of the strengths of Linux, and open source in general, is the diversity of solutions available, I think it's important that there's a movement towards a well integreted set of tools.
As far as I understand it, consoles are sold at a substantial markdown, so that companies can recoup their losses on game sales. Any company that actively supports an emulator for another company's platform keeps the games sales for that platform alive, and profits high.
Do you forsee that the OpenGL extension-approval-integration mechanism will keep pace with Microsoft's iterative improvements to DirectX? Given that feature addition in both APIs appears to be driven by hardware improvements, do you think that this will ultimately be the deciding factor between the two APIs?
Best bet is to get the "Red Book" - the OpenGL programming guide. This is a great book, especially if you're new to graphics concepts. (Although, if you want a good graphics book, Computer Graphics Principles and Practice by Floey, Van Dam et al. is still the best text IMHO).
Just out of interest, how come it took you a day to port some GLUT code to Windows? I thought that GLUT code compiles out of the box on Windows and on Linux and on Mac and on...
OpenGL existed long before consumer level hardware acceleration. I believe it will exist even if it isn't, since no high-level CAD vendors will consider DirectX. Remember, OpenGL exists for a lot more than just games.
Farenheit was supposed to be a joint initiative between Microsoft and SGI in an attempt to unify the diverse graphics APIs. It was thought by many that this was an attempt by Microsoft to appease the developers, coming at around the time when major developers were petitioning Microsoft to continue with OpenGL support in Windows9x - most particularly to do with Microsoft's removal of the MCD model, forcing IHVs to write complete implementations of OpenGL - a non trivial task.
Bits of Farenheit were supposed to appear in DirectX 7. I didn't see them. I read a white paper on the scene graph technology they were talking about - looked interesting. I believe the Farenheit project was eventually 'put on the back burner' a little while ago now.
There was a scare around Christmas when it was reported that OpenGL wasn't making its way into Windows2000 releases. This turned out to be a rumour and nothing more.
On the subject of stagnation of the API: Don't forget that vendors can expose extensions to OpenGL through a well documented and standardised extensions mechanism. This is what happened with multitexture - in GL 1.1 multitexture was exposed via an extension, many vendors implemented it and thus in 1.2 the feature was standardised. It's a very different model to DirectX's 'lets throw everything we can think of in this year and give em another interface to play with' development. The point is that OpenGL was designed properly in the first place.
good: id has long been a fantastic technology company, but for several games now has been criticised for lack of quality content. I think they brought this around a bit with Q3A, but it does seem now that they are actually going after *good games* as well has good-looking ones. Doom was great, and scary, and I can't wait to see an Arch-vile again after all these years...
bad: From an outsider's point of view, it does seem that Paul Steed was instrumental in adding atmosphere to the games that id made. Plus political infighting does not bode well for the future of one of the most important pc game houses around.
Of course, this is all based on John Carmack's plan update, and so it'll take a while for the whole story to emerge, if it ever does. But I look forward to what iD do next - the question is whether they'll stay a cohesive unit long enough to do it.
Slashdot Mirror
Huh?
Bump mapping is a way of representing high frequency geometrical detail on a low frequency approximation. It has a few disadvantages, (depending on how you do it) - try looking at a bump mapped surface side on, and you'll see nothing but flatness.
This doesn't really have much impact on modelling cloth.
Incidentally, the effect you mention in Unreal is called detail texturing, which involves modulating the source texture with a high resolution, but smaller texture at proximity.
Henry
Hugo Elias
Chris Hecker
Jeff Lander
Henry
Computer graphics is an exercise in modelling.
Practically every technique that is in use in graphics today (specifically, and particularly, in games), is a model, an approximation to the real world. Texture mapping, polygonal approximation, simplistic lighting models - all of these are convenient, efficient, and realistic looking models of real life.
What the story appears to say is "computers are far away from this particular model". Well, that's always going to be true, since the model can always get more realistic and detailed, up until the limits of understanding particle interaction in modern physics.
The presentation itself is very interesting, and also presents some models that are somewhat feasible for limited use in today's applications.
Henry
Microsoft have been very keen to show that the CLR is not tied to just one development language. They have guys working on, for instance, and ;Co bol(!) implementations, which seem to be a proof-of-concept demonstration of the independance of the CLR. While, as the article is at pains to point out, the basic concepts aren't new (although what in computer science is?), it seems to me that the .NET framework represents a interesting and new set of ideas to work with. Bear in mind, as another poster pointed out, that there is no reason the .NET framework cannot be ported. But even if not, it seems a little unreasonable for to lambast microsoft for producing something as obviously fully developed as this.
Admittedly, using propietory keywords in C++ is a horrible thing to do.
Henry
Not 3dlabs fault. I can't remember who originally coined the term, but it's been around for a while. A voxel is a volume pixel (pixel = picture element), and thus has width, height and depth. They were used in Command & Conquer: Tiberian Sun (although I don't know whether they were preprocessed down to sprites).
The nomenclature is sound.
Gingko
switching to another modelling paradigm is not just a case of 'ooh it goes fast!'. The use of polygons is so ingrained in computer graphics today that to move to another primitive would involve a lot of effort.
AFAIK, artist's 3d tools are geared towards polygonal based rendering. It's not a given that artists will find voxels intuitive to model with (although it may be that the raster-vector analogy stands). I'm not an artist so I don't know. But one of the challenges will be providing decent tools.
More significantly, many of the fundemental problems in computer graphics, such as visibility and lighting, have been solved in efficient ways for polygons in particular. I'm not greatly familiar with the current state of affairs in voxel based research, but there's a lot of basic techniques that are used today in polygonal-based rendering aside from drawing filled spans that may not translate directly to a new paradigm.
Perhaps the fact that the accelerator is a hybrid is key, since the different representations can be applied to more suitable constructions. But I think there's a way to go before voxels become mainstream, simply because they don't translate directly to polygons, and hence the class of problems associated with primitive rendering is not already solved.
Gingko
is this incorporated with Glade. While one of the strengths of Linux, and open source in general, is the diversity of solutions available, I think it's important that there's a movement towards a well integreted set of tools.
Gingko
As far as I understand it, consoles are sold at a substantial markdown, so that companies can recoup their losses on game sales. Any company that actively supports an emulator for another company's platform keeps the games sales for that platform alive, and profits high.
Does that sound like a Microsoft tactic?
Gingko
Do you forsee that the OpenGL extension-approval-integration mechanism will keep pace with Microsoft's iterative improvements to DirectX? Given that feature addition in both APIs appears to be driven by hardware improvements, do you think that this will ultimately be the deciding factor between the two APIs?
Gingko
Best bet is to get the "Red Book" - the OpenGL programming guide. This is a great book, especially if you're new to graphics concepts. (Although, if you want a good graphics book, Computer Graphics Principles and Practice by Floey, Van Dam et al. is still the best text IMHO).
.
The Red Book is available online here
Some good tutorials are here
For general information, plus a lot of good links, www.opengl.org is the place to look.
Gingko
http://www.sgi.com/fahrenheit/index.html
gives SGIs take on why they no longer support Fahrenheit.
Gingko
Just out of interest, how come it took you a day to port some GLUT code to Windows? I thought that GLUT code compiles out of the box on Windows and on Linux and on Mac and on...
Gingko
OpenGL existed long before consumer level hardware acceleration. I believe it will exist even if it isn't, since no high-level CAD vendors will consider DirectX. Remember, OpenGL exists for a lot more than just games.
Gingko
In response to the question about Farenheit:
Farenheit was supposed to be a joint initiative between Microsoft and SGI in an attempt to unify the diverse graphics APIs. It was thought by many that this was an attempt by Microsoft to appease the developers, coming at around the time when major developers were petitioning Microsoft to continue with OpenGL support in Windows9x - most particularly to do with Microsoft's removal of the MCD model, forcing IHVs to write complete implementations of OpenGL - a non trivial task.
Bits of Farenheit were supposed to appear in DirectX 7. I didn't see them. I read a white paper on the scene graph technology they were talking about - looked interesting. I believe the Farenheit project was eventually 'put on the back burner' a little while ago now.
There was a scare around Christmas when it was reported that OpenGL wasn't making its way into Windows2000 releases. This turned out to be a rumour and nothing more.
On the subject of stagnation of the API: Don't forget that vendors can expose extensions to OpenGL through a well documented and standardised extensions mechanism. This is what happened with multitexture - in GL 1.1 multitexture was exposed via an extension, many vendors implemented it and thus in 1.2 the feature was standardised. It's a very different model to DirectX's 'lets throw everything we can think of in this year and give em another interface to play with' development. The point is that OpenGL was designed properly in the first place.
Gingko
This seems to be a good and bad thing.
good: id has long been a fantastic technology company, but for several games now has been criticised for lack of quality content. I think they brought this around a bit with Q3A, but it does seem now that they are actually going after *good games* as well has good-looking ones. Doom was great, and scary, and I can't wait to see an Arch-vile again after all these years...
bad: From an outsider's point of view, it does seem that Paul Steed was instrumental in adding atmosphere to the games that id made. Plus political infighting does not bode well for the future of one of the most important pc game houses around.
Of course, this is all based on John Carmack's plan update, and so it'll take a while for the whole story to emerge, if it ever does. But I look forward to what iD do next - the question is whether they'll stay a cohesive unit long enough to do it.
Gingko