Questions tagged [projection-matrix]
The projection-matrix tag has no usage guidance.
projection-matrix
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Aspect ratio affecting 3d projection in wierd ways [duplicate]
The details of the problem.
Hey, im a newbie in computer graphics and I need some insight on a problem. I am using Pygame and projection matrixes to render a simple rotating cube. When I run the ...
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z value in NDC outside [-1...1]
I'm trying to write a simple graphics pipeline, I encountered a problem in NDC. The coordinates are out of range from -1 to 1, while the top is clearly inside the camera pyramid (near plane at a ...
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1
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Why is my FOV Perspective Matrix4x4 looking Orthographic (DotNet and SkiaSharp)?
Brief overview, you can image I'm drawing points of a 3D schematic onto a Canvas, think CAD.
I have points in 3D XYZ Vector3 coordinates, and I've got a model, view, projection matrix all setup. I've ...
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Custom Java 3D renderer is breaking when implementing a perspective projection
I'm not very experienced with Java or computer graphics, but I thought I'd try and program a rough 3D engine in Java as I've been finding APCS pretty fun. I've gotten as far as implementing vertices, ...
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In p5.js vertex shaders, why sometimes there are matrices used and sometimes not to compute gl_Position?
I am trying to learn shaders and started looking at several examples.
As I am using p5.js, in some vertex shader examples I can see this kind of computation:
attribute vec3 aPosition;
void main() {
...
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Face Image Rotation using camera matrix and 3D morphable model?
community, I am trying this code for 3D face reconstruction. How can I generate front output faces in the test step? is this related to the camera_matrix or the 3DMM model? I mean I want to fix the ...
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Optical flow from NeRF
I am working with Instant-NGP TL. I am trying to calculate the optical flow using the output of the volume rendering. My approach to this is the following:
Take sampled points along each ray ...
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To save object that has projected materials as glb file
I have three.js app that project images to object.
Now I want to save that object as glb file.
Here is an issue. The projected material is not saved. I can't see it when I open the saved glb file with ...
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CesiumJS: compute the projected size of the globe (in pixels)
We are using CesiumJS as an overlay in a spherical geometry app where it renders its own sphere with a known size (in pixels) and the user may zoom in/out to change its size.
We would like to ...
- 166
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Implementing Camera Movement and Rotation in 3D Game Engine
Apologies in advance for any mistakes on terminology, I'm really really new to this
I'm completely new to 3d (and it's maths) but as a personal exercise I'm doing my own game engine that displays a ...
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Issue with transforming a 3d point to screen coordinates
I have a point cloud in 3d world space that I would like to render to the screen by projecting it's individual points using an MVP matrix. But something about the projection seems off. There appear to ...
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LWJGL Projection Matrix not working (Quad remains the same even after multiplying with Projection Matrix)
I programmed a LWJGL 3 code to render a quad on the screen. I even added the projection Matrix to it, still I don't see any changes in the appearance of the quad. If I change the FOV of the frustum ...
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Why are two elements of my inverse projection matrix always 0?
I'm writing a ray tracer for which I need to cast rays from the screen into the world. I'm using the inverse of the view-projection-viewport matrix to get back from screen pixel coordinates to world ...
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Calculating the Normalized Device Coordinates from World Coordinates
After researching, I tried to implement a Vector3 object that represents a 3D point. I want to get the Normalized device coordinates, which if I understood correctly, the x, y, z values should fall in ...
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Rotations for 3D perspective projection not working
I have implemented a 3D perspective projection matrix into a simple program. The projection works great but when I apply rotations in the x and y axis, they don't look right. However rotation in the z ...
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