Questions tagged [projection-matrix]
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68 questions
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Easy 2d custom shader for Unity 3d: charts, flat/ortho mesh, etc
I just need to draw a flat mesh (say a 2d graph) on top of everything. What could be easier? create an object, adding it a mesh precalculated in homogenous (-1,+1) coordinates to match ...
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Problem with 2D projection
I have a green circle:
Inside the circle, the white frame moves to wherever P, the projection of the targets 3D position into a 2D point, is.
However, outside the circle, the frame will move to the ...
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Setting up perspective projection in OpenGL
I'm trying to set up perspective projection in OpenGL but it doesn't work
...
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How to obtain the Position on the screen (Vector2) of the Position of an object in the world (Vector3)?
I have been searching around for a solution to this but still haven't been able to use it or find it, the thing is i need the Screen Position of an object that is being seen, for this i have three ...
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How to Generate a Texture to Make an Obstructing Plane Appear Invisible in a 3D Scene?
I have a 3D scene with a camera. Between the camera and the scene, I have a plane with arbitrary orientation. This plane obscures a portion of the scene from the camera’s perspective (anything behind ...
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How do I create a localtoworldmatrix and worldtolocalmatrix in Godot?
From what I can tell Godot uses Projection for 4x4 matrixes, but I see no way to generate a localtoworldmatrix from a given transform in Godot, how do I do this?
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How to correctly rotate 2D orthographic projection around a central point?
I want to rotate a 2D orthographic projection around the centre point of my view. However, something is off (it looks like a translation) but I'm not sure what.
To put some concrete values on the ...
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glm::frustum vs glm::perspectiveFov
When I use glm::perspectiveFov(90.0f,512.0f,512.0f,1.0f,256.0f) I receive a working perspective projection with 90° in both x and y, as seen below (camera is in ...
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Is directional shadow mapping without projection matrix possible?
I have found this code where they use a cubemap for pointlight shadow and they don't need to retrieve the faceindex and the projection matrix. This greatly improve the FPS. I was wondering if this ...
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In a 3D projection, how to find 'w' for every y point on the screen
I have a standard 3D rendering pipeline. Let's say I have a camera looking down at a flat plane that represents the floor. (in my game, z = height, so this is a plane where z == 0), and for ...
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When moving the "camera" should one move the projection matrix or move the world?
I'm making my own game engine as an exercise and I've gotten really confused with what I've read so far.
When I want to move my camera do I simply just move the world or move the position of the ...
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How are transformation matrices usually represented?
I know the bare minimum to do matrix multiplication and have implemented them from scratch a few times for various purposes, but every time I do, I make sure to be very clear to myself about where are ...
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How to visualize angle of projection in Oblique Parallel Projection?
We know that in Oblique Parallel Projection Point (x,y,z) is projected to position (x_p,y_p) on the view plane.Projector (oblique) from (x,y,z) to (x_p,y_p) makes an angle alpha.
with the line (L) on ...
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How to get world coordinates from a 4X4 camera matrix
I have Intel T265 camera which has a camera coordinates system like following diagram:
The camera system has two cameras and the center of the two cameras is the position of the camera system.
The ...
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How does glm::lookAt produce a View Matrix?
Say we do this:
glm::mat4 View = glm::lookAt(glm::vec3(4,3,-3), glm::vec3(0,0,0),glm::vec3(0,1,0));
And after printing to the console with glm tostring (column ...
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