Timeline for How to project spherical coordinates to canvas
Current License: CC BY-SA 3.0
12 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| May 20, 2014 at 1:17 | history | tweeted | twitter.com/#!/StackGameDev/status/468561025575317505 | ||
| May 19, 2014 at 18:19 | vote | accept | Christoph | ||
| May 19, 2014 at 16:05 | answer | added | bcrist | timeline score: 3 | |
| May 19, 2014 at 14:05 | history | edited | Christoph | CC BY-SA 3.0 |
added links to gnomonic and perspective projection
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| May 19, 2014 at 12:09 | comment | added | DMGregory♦ | Ah, if you use a perspective matrix, with your viewpoint at the center of the sphere, then what you get is called a Gnomonic projection. en.m.wikipedia.org/wiki/Gnomonic_projection - It may be worth updating your question to use this term, so others searching for it can find it. | |
| May 19, 2014 at 8:42 | comment | added | Christoph | @bcrist I think that if you rephrase your comment as an answer, I can accept it. There might be a follow-up regarding camera angles, but that's a different question, if it really turns out to be a problem. | |
| May 19, 2014 at 7:04 | comment | added | Christoph | @bcrist I think "perspective projection matrix" is the term I was missing. A rotation view matrix is probably just a rotation matrix as I already know it from mechanics? And yes, I want it to look like being at the sphere's center, looking at the sphere from the inside. | |
| May 19, 2014 at 7:00 | comment | added | Christoph | @DMGregory a lower resolution far away from the view's center is not bad because the field of view is small (10° across). | |
| May 19, 2014 at 0:01 | comment | added | bcrist | It's not really clear what kind of projection you're talking about. If you want it to look like you're inside a sphere looking at it's inside surface, you just need to convert your spherical coordinates to Cartesian coordinates and use a basic rotation view matrix and perspective projection matrix to convert points from world-space to clip-space. | |
| May 18, 2014 at 23:47 | comment | added | DMGregory♦ | Can I clarify what kind of projection you're looking for? Any one orthogonal projection won't have a constant resolution everywhere on the sphere. The resolution is greatest where the view vector is perpendicular to the sphere, and falls to zero in one axis where it's tangent to the sphere. Another option is equirectangular projection, which maintains equal latitudinal and longitudinal resolution everywhere, but is not equal-area: objects distant from the projection's equator are stretched horizontally, infinitely so at the poles. | |
| May 18, 2014 at 17:34 | review | First posts | |||
| May 18, 2014 at 21:48 | |||||
| May 18, 2014 at 17:18 | history | asked | Christoph | CC BY-SA 3.0 |