Computer Graphics: Principles and Practice (3rd Edition)

Category: Programming
Author: John F. Hughes, Andries Van Dam, James D. Foley, Steven K. Feiner
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by anonymous   2019-07-21

It is quite hard to tell from your height map (primarily because you haven't got any lighting on it) but I'd say its near definite that in your examples they are using high resolution base height maps than you are.

Now unlike what some of the other posters suggest it is highly unlikely the landscape is being modelled in a 3D modelling package. It is also highly unlikely they are using B-splines to render the landscape.

The big problem with using a higher resolution height map is the memory requirements. To this end there are multiple different solutions that "optimise" the height map data that is stored in memory. Nearby landscape does not need as much details as the landscape far away.

A really good technique for rendering VAST amounts of highly detailed landscape geometry is geometry clipmaps. It's quite complicated though. Another scheme I have used to great success in the past is Geo-Mipmapping. It's very simple and very fast. It produces excellent results, too, if you apply trilinear filtering techniques to your Geo-mipmaps. It is also fairly trivial to write an asynchronous chunk loader for such a landscape to provide good streaming performance of huge landscapes.

Anyway I'll answer your other questions.

  1. As suggested by hbdavehb they will have an editor that loads the landscape and they can then place items on the map (as well, most probably, as editing the landscape). The models will be created in 3DS Max or Maya and then loaded into the editor for placing.

  2. They are rendered with some other form of renderer. Often a portal renderer or maybe a BSP renderer.

  3. This technique is known as texture splatting.

  4. Looks like a skybox to me. It could I guess be a dynamic rendering ONTO a skybox.

  5. The list is huge. But I would suggest looking into various image mapping techniques such as bump mapping (Especially normal mapping), cube mapping, Parallax mapping, Displacement mapping. Then there would be the lighting techniques such as global illumination, the Phong illumination (not the same as Phong shading), bidirectional reflectance distribution functions and precomputed radiance transfer. That's only scratching the surface. I highly recommend having a good read around. Computer Graphics: Principles and Practice by Foley et al. is an excellent book on rendering. The GPU Gems series is very good too. For a history of 3D rendering techniques and, in my opinion, still a very useful book its worth looking at Michael Abrash's Black Book as well.

Good luck!

by anonymous   2019-07-21

Computer graphics principles and practice (Foley et al) defines the 2 as follows:

Texture mapping can be accomplished in two steps. A simple approach starts by mapping the four corners of the pixel onto the surface. For a bicubic patch this mapping naturally defines a set of points in the surface's (s,t) coordinate space. Next, the pixel's corner points in the surface's (s,t) coordinate space are mapped into the texture's (u,v) coordinate space The four (u,v) points in the texture map define a quadrilateral that approximates the more complex shape into which the pixel may actually map due to surface curvature. We compute a value for the pixel by summing all texels that lie within the quadrilateral, weighting each by the fraction of the texel that lies within the quadrilateral. If a transformed point in (u,v) space falls outside of the texture map, the texture map may e though of as replicated, like the patterns of Section 2.1.3 Rather than always use the identity mapping between (s,t) and (u,v), we can define a correspondence between the four corners of the 0-to-1 (s,t) rectangle and a quadrilateral in (u,v). When the surface is a polygon, it is common to assign texture map coordinates directly to its vertices.

by anonymous   2019-07-21

mate. Your question is not of simple answer. I would explain the maths to you if I remembered. But it's been some time since I don't study linear algebra.

First, the methods you would call to do that uses the math you are looking for, and it is probably optimized!

But, regarding your questions about the maths behind it, here is a link: https://en.wikipedia.org/wiki/3D_projection

This "3d vector to 2D vector screen point" is called projection, and you are probably referring to perspective projection. It is explained in the link.

If you are interested in learning it, you should first study some linear algebra, and then start studying computer graphics. (One good book: http://www.amazon.com/gp/product/0321399528/ref=as_li_qf_sp_asin_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=0321399528&linkCode=as2&tag=casueffe06-20)

by deepaksurti   2018-10-04
Computer Graphics:

[1a, 1b, 1c] Computer Graphics, Principles and Practice Series [2] Physically Based Rendering [3] Real Time Rendering

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[1a] https://www.amazon.com/Computer-Graphics-Principles-James-Fo... [1b] https://www.amazon.com/Computer-Graphics-Principles-Practice... [1c] https://www.amazon.com/Computer-Graphics-Principles-Practice... [2] https://www.amazon.com/Physically-Based-Rendering-Theory-Imp... [3] https://www.amazon.com/Real-Time-Rendering-Third-Tomas-Akeni...