Talk:Heightmap

Program list

I removed the list of programs that use heightmaps as it doesn't really add anything to the article and is a magnet for spam.--Drat (Talk) 12:06, 12 September 2006 (UTC)

I highly disagree with your decision. In fact, I had problems finding such software and when I checked the version history I realized that someone had removed it. The list was useful and could have been expanded; it did not seem like spam. Many other such articles have lists of programs. I may restore the list later, as it does list useful programs for the purpose. I believe removing such a list degrades the article's quality and content. If we allow the list then it can get expanded as well. The great kawa 05:07, 23 October 2006 (UTC)

I am being bold and I am restoring the list. It is useful (at least it was to me) and if anyone feels that it is incomplete, then by all means add to it valid programs. The great kawa 23:28, 6 November 2006 (UTC)

We could list the earliest games that used a real-time rendering of heightmapped terrain, such as Comanche and other games using NovaLogic's "voxel space" engine. --Damian Yerrick (☎) 15:42, 31 December 2006 (UTC)

Heightmap vs. voxels

I introduced language relating a heightmap to a voxel field. Someone writing on my talk page suggested that the relationship might be controversial. Here I address some of the concerns:

• "Are voxels necessary?" NovaLogic branded its heightmap based games as using "voxel space technology".
• "What's the abstraction level?" A heightmap is a function from (length, width) to height. The value height is such that all voxels below this height are solid, and all voxels above this height are not solid.
• "I am not sure it would work with float heightmaps" NovaLogic's "voxel" games ran on platforms that did not have floating point hardware.
• "In a certain sense, the heightmap sample value will be the height but when it comes to widht and depth that's another business since the sample is applied to points." Early heightmap games rendered the terrain using ray casting, and for speed, they used nearest-neighbor resampling to get it done. This is exactly equivalent to a run-length encoded voxel field.
• "The idea of thinking at "voxels" seems just a bit overkill" Tell that to NovaLogic.

--Damian Yerrick (☎) 15:49, 31 December 2006 (UTC)

I am still not conviced. The only thing I got is that you're working on a very high abstraction level. Everyone can see a manifold surface representation can be turned in a volume representation. Referring to a specific implementation (a voxel rendering system) does not seem like a good idea to me, especially when considering amost everyone is using polys. I don't see any addressing in the above, but it help me took a decision. I'm being bold and removing voxel references.
MaxDZ8 talk 11:04, 2 January 2007 (UTC)

Was "amost everyone [] using polys" way back when Comanche came out? It might be better to state that early games drew heightmaps columns of voxels and that developers used polygon meshes as polygon hardware became more mature. --Damian Yerrick (☎) 16:03, 4 January 2007 (UTC)

Proposed merges

I can see merging heightfield here, and I'll probably do it three minutes after I submit this comment. But Digital elevation model is a more complicated case, as it refers specifically to the use of heightmaps in GIS. --Damian Yerrick (☎) 16:27, 4 January 2007 (UTC)

In fact, the merger is disputed. --Damian Yerrick (☎) 16:37, 4 January 2007 (UTC)

Do not merge heightmap and DEM. Heightmap is a generic recording of height elevation, used in games, etc. DEM speicifcally refers to a product distributed by an (often-governmental) agency with a claimed representation of some real-world terrain features, along with a claim of a repeatable process, and reported accuracy. DEM is a subset of heightfield, but not an equivlalent. Anyone involved with GIS would hold these two terms very different. Twredfish 23:36, 8 January 2007 (UTC)

Oppose: there are many different methods to find DEMs that are not used for height-field. Yes, the end-products are similar, but they certainly warrant content of their own. +mwtoews 22:50, 13 February 2007 (UTC)

heightmap vs. heightfield

Aren't that different things – at least in theory? Aren't heightmaps images/representations of heightfields?--Speck-Made (talk) 06:39, 14 December 2007 (UTC)

It's open to debate. There's always a level of abstraction in which this similar concepts blur togheter. For example, are machine instructions and operations the same thing? In some context they are, in others they're not. Another example: is humanity the same thing as mankind? I don't think this minor naming issue to be a problem at all and I'm rather sure there's nothing like a definition which comes from an authoritative, trustable and widely recognized source. Cannot we just live with more flexible concepts?
MaxDZ8 talk 08:28, 14 December 2007 (UTC)

Personally i think a Heightmap is a 1D Black and White image (typically tga) used for materials in video games (Such as Unreal) and a Heightfield is a 3D Raster image (typically .raw or .bmp) used to generate 3d Terrains (such as Terragen)

I agree however, Many people would disagree with my statement but i believe yours is more true to the article.

--Jenkins08 (talk) 05:07, 14 April 2009 (UTC)

Hatnote

I added a hatnote linking to "Depth map" because "depthmap" automatically redirects to this article. I am not feeling brave enough to edit depthmap redirect because I am the author of "depth map". I am not sure if depthmap should be made a disambiguation page, be made to redirect to "depth map" or just be deleted. — Preceding unsigned comment added by Dominicos (talk • contribs) 02:47, 26 January 2011 (UTC)

As I see it there is an important difference beween a height map and a depth map: Both show distance information, but a height map contains information about how far a surface or object is lifted up from a basic plane, and is therefore used by computer grafics and in geo systems. A depth map shows the distance of parts of objects, that can be seen from a fixed view point, to that fixed viewpoint, not a plane, and therefore shows totaly different information! It is used in computer vision in the context of ranged imaging, robotics, stereopsis, etc.

Therefore I think it would be a good thing to change the hatnotes a little and keept those two seperate. The Ieee Xplore finds about 3400 articles to "depthmap", and a little less than 2000 to height map. Please take that into account if you want to put these two articles together in any way anyways. --128.176.164.70 (talk) 13:55, 25 September 2012 (UTC)

Limitations

I think there should be a section describing the limitations of heightmaps - the most critical of which being the inability to model overhangs or caves, since each point must have only one height value. I could discuss some of this myself, but it would probably be considered original research and taken down. Not sure where a good source for that would be. Lurlock (talk) 17:25, 22 August 2013 (UTC)