All Questions
Tagged with projections 3d
35
questions
0
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1
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345
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How does 3D graphic software adjust for distortion inherent in perspective projection?
As this question and its answers point out, projecting a sphere on a flat picture plane, with perspective projection, may result in a ellipse, not a circle, and my understanding is that the only way a ...
- 129
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91
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Consistent Video Depth Estimation from Monocular Lens to approximate LiDAR?
If the iPhone had LiDAR sensors, it would be possible to generate a 3D point cloud that you could theoretically use to furnish a 3D AR reconstruction of your surroundings. E.g. you could create an AR ...
- 101
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votes
1
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120
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Keep constant number of visible circles in 3D animation
I have created a 3D animation with a perspective projection of white circles moving randomly in a fake 3D space projected on a 2D computer screen (GIF 1).
Since I need to keep the same number of ...
- 113
2
votes
1
answer
121
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Y axis inversion in 3D rasterization
What is the correct way to invert the y axis during the 3D projection?
I see a lot a people doing:
...
- 269
2
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1
answer
1k
views
Intrinsic Matrix vs Perspective projection matrix
I was going through the camera matrix explained in the wikipedia article and understand how the matrix K \begin{bmatrix}f_x&s&x_0\\0&f_y&y_0\\0&0&1\end{bmatrix} is built. The ...
- 121
0
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1
answer
882
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Understanding the near clipping plane
I don't understand something about the near clipping plane. It's there to avoid the division by $0$ but when we compute the pixel coordinates, we just need to multiply by the clipping plane to clip ...
- 269
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1
answer
506
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Why is the z direction away from the screen/viewer?
I wonder what is the reason that when z increase, the objects appear far away and when z is negative, the object is behind the camera?
- 269
3
votes
3
answers
3k
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3ds max: Z-fighting when working with Large Objects
I had a z-fighting/z-clipping issue with a scene containing some very large objects yesterday in 3ds max. It can be seen in the image below:
For some reason downscaling the scene significantly (a ...
1
vote
1
answer
246
views
Overlaying a grid on to a height map
What is the method used in overlaying a grid (agonostic of the grid type) on to a height map? It seems it's some sort of projection, but what are the technical details in how to implement it?
An ...
- 143
0
votes
1
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273
views
How to compute A and B in projection matrix
I'm trying to compute a projection matrix to transform from view space to NDC with a near clip plane at -1 and far plane at +1. The general form of this matrix (disregarding aspect ratio and focal ...
- 520
3
votes
0
answers
98
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Possible approach for product mockup creation including distortion created through perspective
I am not an expert in 3D nor computer graphics. Please forgive me if I use wrong wording.
High level problem description: For an online shop, I would like to create mockup images of apparel (t-shirts,...
- 131
1
vote
2
answers
112
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If a 3D scene is rendered onto a hemispherical display, will there still be warping near the edges?
When a 3D scene is rendered to a 2D display, the image is distorted near the edges of the display.
If a 3D scene is rendered onto a hemispherical display, will there still be warping?
- 113
2
votes
1
answer
16k
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How to derive a perspective projection matrix from its components?
This has been haunting me for several days now. I want to find the component that makes up of this 4x4 perspective projection matrix, with $l$(left), $r$(right), $b$(bottom), $t$(top), $n$(near), $f$(...
- 207
0
votes
2
answers
278
views
The distance from the cube sides to the parallel projection plane
I have asked this question on ru.stackoverflow.com and have no valid answers.
Specification:
Coordinate system
Cube spins around its center on all three axes.
Turn angle is not known previously.
...
user7220
6
votes
1
answer
785
views
3D projection that increases objects' size as they become more distant
tl;dr Is there a name for a type of (non-physical) projection that causes objects to become larger the farther they are from a camera?
With a fisheye projection, an object twice as far from the ...
- 195