Celestia Forums

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John, thank you for your efforts to improve Celestia.

However, I have to add something;

here you see the poles of my mars-storm rendering in Photoshop:


What could I do more? I think this looks very accurate...

and here you see the same map in Celestia;
it's the official map from noaa.gov (ftp://public.sos.noaa.gov/astronomy/mars/original/4096.jpg) with the "dust"-overlay.


Do you notice something?
Or here; the Mars map of the official Celestia release 1.6.0...


And so on. Nearly every texture map in Celestia is showing these faults in the polar area.

Regards
Michael

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Michael,

And so on. Nearly every texture map in Celestia is showing these faults in the polar area.

Regards
Michael

I disagree. My old 32k Mars VT texture doesn't show the slightest bit of polar pinch! Here is the region around the pole, so you can see yourself:



Analogously, the circle in the following image marks the Earth's south pole in my optimized 64k tile set. The mountaineous glacier range at the bottom is very close to the pole since this is really hires!
NO PINCH whatsoever either:




There are several efficient "weapons" against the polar pinch that experts know for quite some time. These include:

1) Switch on ~ 8x Anisotropic filtering (AIF) in your graphics card!! Even for old graphics cards, AIF does not slow down the display much (unlike anti-aliasing).

2) Make VT' textures with the help of my texture tools (http://forum.celestialmatters.org/viewtopic.php?t=70) , since my tools reduce the nominal VT resolution towards the poles yet keep the effective resolution constant!

Note that for given latitude, the xy-radius of a spherical body decreases towards ZERO near the poles. Wrapping a standard rectangular texture map around a body in the polar region will thus generate a large number of partially overlapping VT's --thus enhancing polar pinch--, UNLESS the widths of the VTs is reduced according to a simple "no-overlap" formula towards the poles. That's what my tools do uniquely.

3) There are further anti-pinch optimization steps that are being incorporated in my texture tools for making VTs.

4) One may consider cube maps that Celestia also supports. While there is no polar pinch with cube maps whatsoever, one has to fight against visible discontinuities along lines where the various projected faces meet...


Fridger

john Van Vliet wrote:and if most of the "fictions" addons are like this then the ML will turn into a joke ( after a few years of this )

The ML is *ALREADY* a joke ! It's not even funny !

Wow, thanks for insulting everybody who has uploaded an addon there that doesn't fit perfect standards.

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Fridger,

t00fri wrote:

MiR wrote:And so on. Nearly every texture map in Celestia is showing these faults in the polar area.

I disagree. My old 32k Mars VT texture doesn't show the slightest bit of polar pinch!

In regard to maps come within Celestia 1.6.0...

I entirely agree with John, he wrote:

john Van Vliet wrote:at low res ( 2048x1024) the maps do not render well at the poles in celestia
VT's except for level0 and level1 render much better in celestia

t00fri wrote:There are several efficient "weapons" against the polar pinch that experts know for quite some time. These include:

1) Switch on ~ 8x Anisotropic filtering (AIF) in your graphics card!! Even for old graphics cards, AIF does not slow down the display much (unlike anti-aliasing).

2) Make VT' textures with the help of my texture tools (http://forum.celestialmatters.org/viewtopic.php?t=70) , since my tools reduce the nominal VT resolution towards the poles yet keep the effective resolution constant!

Note that for given latitude, the xy-radius of a spherical body decreases towards ZERO near the poles. Wrapping a standard rectangular texture map around a body in the polar region will thus generate a large number of partially overlapping VT's --thus enhancing polar pinch--, UNLESS the widths of the VTs is reduced according to a simple "no-overlap" formula towards the poles. That's what my tools do uniquely.

3) There are further anti-pinch optimization steps that are being incorporated in my texture tools for making VTs.

4) One may consider cube maps that Celestia also supports. While there is no polar pinch with cube maps whatsoever, one has to fight against visible discontinuities along lines where the various projected faces meet...


Fridger

Thanks!

Some months ago I already downloaded your texture tools. Yet I haven't found the time to search and download suitable Earth or Mars files.
I'm convinced your texture tools are excellent; the examples of the Mars and Earth VT's looks pretty good!


Cham,

Cham wrote:The ML is *ALREADY* a joke ! It's not even funny !

I can't understand your comment about CML. Sometimes it's not easy to make a clear difference between "Fiction" and "Science Fiction".
I think CML has found a good solution with the subdivision of categories...
And for younger people it might be a way of approaching into the "higher aspects of Celestia".

But I entirely agree: some fictional renderings looks more like a picturesque wallpaper pattern than a planetary map

One word, please;
Let me take this opportunity to say:
I like your magnetic field add-ons more than much. Because with these magnetic lines you're showing forces we're not able to see.
Therefore a very big "Thank You!"

Regards
Michael

Cham wrote:

john Van Vliet wrote:and if most of the "fictions" addons are like this then the ML will turn into a joke ( after a few years of this )

The ML is *ALREADY* a joke ! It's not even funny !

These remarks are uncalled for IMO... the ML is a repository, run by volunteers... for free. You also are free to make your own mind up about what to add-on and what not to.

This sort of comment smacks at elitism.

For what concern ML's "joke" add-ons, I think that isn't taken into consideration the evolutionary aspect of the issue. Does Windows 7 looks like Windows 3.1? Does Posette character looks like Victoria 4? Does DOOM 1 looks like DOOM 3? etc. So the add-ons follows such "rule". Old add-ons looks diversely, accordingly with the standard of the times. When consumer graphic cards will have n terabyte of VRAM, probably VT no longer will be tiled by softwares.

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I've yet to see any examples of what the OP thinks IS a good map.

Unless I missed something?

bh wrote:

Cham wrote:

john Van Vliet wrote:and if most of the "fictions" addons are like this then the ML will turn into a joke ( after a few years of this )

The ML is *ALREADY* a joke ! It's not even funny !

These remarks are uncalled for IMO... the ML is a repository, run by volunteers... for free. You also are free to make your own mind up about what to add-on and what not to.

This sort of comment smacks at elitism.

This whole thread smacks at elitism.

From my perspective, it seems the Celestia community, and perhaps Celestia itself, is becoming more and more elitist.

No offense intended, this is just my perception.

and most defiantly if a B&W only jpg is used and not a Black and transparent png

So should spec maps be png's with the white transparent? You lost me on this comment. Sorry.

Here is what I see, blotches.jpg is with the OpenGL 2.0 render path, noBlotches.jpg is using the openGL vertex program path.

Thanks John,
Tim

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