Questions tagged [projections]
Questions about the conversions of a 3D model to a 2D model.
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Project grid on 2d plane based on camera perspective
Unsure if this is the right network to post this, but maybe someone can help...
I'm working on a personal project where, with the help of AI, I want to automatically estimate the perspective of a ...
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Formula for cubemap resolution for intended equirectangular resolution
Suppose I want to render out 6 cubemap cameras (90 degree FOV etc.) with the intention of combining them together in post-production into an equirectangular (latlong, 2:1) image.
Suppose I also know ...
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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,...
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Calculate Camera parameters and HandEyeCalibration
I'm trying to calculate camera paramters and a hand eye calibration (Transformation from camera to eye (display) coordinates) for rendering on a see-through HMD.
I have already calculated a ...
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3
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A question about derivation in oblique view frustum
Problem Description:
Reference:
Oblique View Frustum Depth Projection and Clipping
"Mathematics for 3D Game Programming and Computer Graphics" 3rd edition, chapter 5.6.
M is the original projection ...
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Finding Camera projection matrix from known input and output
Lets say I have a rectangle with known coordinates in 3D scene, and I'm projecting it using pin point camera to the plane (screen).
You can imagine it deforms on the screen per camera transformation ...
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What is the best way to calculate the projected size of a point
In a particle simulation, I am rendering particles as "spheres" using GL_POINTS instead of a mesh for efficiency. With glEnable(GL_PROGRAM_POINT_SIZE) I ...
user15232
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Project a Square as rectangle in projection plane using perspective projection
Consider a square S with vertices (1,1,0), (1,-1,0), (-1,-1,0) and (-1,1,0) and a plane P defined by $z=1$. Let the perspective projection of S on P is denoted by S'.
What coordinates of the Center ...
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Projecting a point on a Freefrom surface
My first issue is getting a set of planes and a set of points as input, an find the projection of the those points on the nearest plane.
That was pretty easy, where i just calculate the normal of the ...
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Make 3d objects from 3 projections in 3D Studio Max
In the early 3D Studio days before it got Max in its name it was possible to make a 3d object by defining its projections in xy, xz and yz plane. 3ds would then interpolate a 3d object from the ...
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How to project a view frustum in an orthographic cuboid?
I know that OpenGL uses a projection matrix to project the view frustum directly into the canoical volume [-1, 1]^3. But how would I project the frustum into an orthographic cuboid, which would then ...
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Is it possible to render to a octahedron texture directly?
I am considering using octahedron textures for environment mapping, opposed to sphere or cube mapping due to their low memory footprint and the quality they result in.
Is there a possibility to render ...
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What should be considered the origin of a ray used for object picking with perspective projection
I need to create a ray to pick objects in 3d environment using cursor.
I'm not going to go into detailed math for this question. There's tons of information on that. In short terms, for orthogonal ...
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Model View Projection Matrix Multiplcation Order
I'm working on a simple software renderer and have a working implementation so far. I'm curious as to why it's actually working since I would expect the multiplication ordering for my world, view and ...
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Why does my self-written rendering engine make further away objects look larger?
I am writing a very simple rendering engine. I have already made a few tests, but somehow the images it creates look wrong. Objects that are further away from the camera look larger than objects ...
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How to Pan Zoom a spherical camera?
I asked this in regular SO but I think people are not understanding the question so i will try here:
So, for anyone familiar with Google Maps, when you zoom, it does it around the cursor.
That is to ...
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3D reconstruction using 2D matched points
I have 2 images, called left and right images. I have some matched points $[c_l,r_l]$ and $[c_r,r_r]$ in both of them (these points are in pixel coordinates).
For a 3D point in the real world, they ...
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Program to visualize geodesics and linear projection of an ellipsoid simultaneously
I am trying to solve a problem in computer graphics but to do it I need to be able to see a comparison of geodesic lines and straigth line projections on the ellipsoid.
I have not been able to ...
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3
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518
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What projection matrix and world transformation do I need to have an isometric projection?
I'm doing my own engine in college to display a wireframe on screen with an isometric projection but I literally can't find any literature about maths behind doing it by hand just for game engines ...
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Ocean screen grid projection and animation
I am trying to port the Bruneton Ocean demo to Vulkan and I am having a bit of trouble with the coordinate system. I am using the matrices from the original code but I am not sure what this is doing:
<...
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Name of non-standard perspective projection where parallel lines do not meet at a single vanishing point
I have made a non-standard perspective projection for a rectangular room (see left figure), in which for stylistic reasons, I chose to make the perspective "width" of the walls equal ...
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Determine horizontal FOV of a panoramic photo
Say I have a panoramic photo (less than 360) and would like to view it in a cylindrical screen in a VR headset to get an immersive experience. How to determine the optimal width and height of the ...
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How to extract points corresponding to faces from cube map projection (CMP) of panorama from point cloud data
I am working with the standford2d3d dataset http://buildingparser.stanford.edu/dataset.html which contains panoramas of various scenes and a .mat file of the point cloud information of all the scenes. ...
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Object appears in unintended parts of the screen when using manual WorldToScreenPoint
Hy guys I'm new to 3d graphics and i lack some Linear algebra knowledge. I tried to recreate Unity's worldToScreenPoint method with kotlin on android. I copied some code from their forum and wrote ...
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3D engine projection distortions
I'm trying to write my own 3D engine using Python and Pygame.
I have successfully implemented rotation and projection matrices to display 3D models. However I am so far unable to implement translation ...
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Alternate projections in shader
I have a projection calculation which maps points from 3D space to pixel (image) space, and I want to use it as instead of the standard MVP projections in a vertex shader.
In the image below the lower ...
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computing sheared perspective projection matrix
is it possible to calculate a "projection matrix" which is sheared as well?
the usual perspective projection matrix forms a pyramid where the near clipping plane is rectangular.
I have 4 ...
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Can surface normal be used for obtaining points on a plane?
Excuse my wording. I will use the picture below to explain what I mean. I want to use the surface normals for each arrow shown like below to draw lines parallel to each plane like the image shown ...
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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 ...
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Does rotating object inside unit cube [-1,1] by homogenous matrix move it outside unit cube
I am just trying to rotate my pointcloud object which is inside the unit cube ([-1,1] in all x,y,z axis). What I did is use the basic rotation matrix from wiki and extend it to homogenuous 4x4 matrix (...
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