Questions tagged [projections]
Questions about the conversions of a 3D model to a 2D model.
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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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How to decompose projection matrix?
I want to decompose projection matrices into near, far, top, bottom, left and right values to create a bounding box for view frustum. I used the formula described in this site Decompose the OpenGL ...
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How would I convert a picture of a slanted surface into a straight one? [duplicate]
Suppose I took a picture of a whiteboard at an angle. If I could detect where the corners of the whiteboard are, what algorithms and linear projections could I use to convert this slanted view into a "...
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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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Existence of vanishing point
Consider the following example of perspective projection: I have one railway track with two parallel lines meeting at the point $X$ at infinity which is the theoretical approach. This X is called the ...
user17337
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What is this graphical effect called?
I was watching this trailer:
https://www.youtube.com/watch?v=pWh5388AEHw
and at 1:22, the player used a magic trick that created a sphere that warped the projection of the scene.
Does anyone know ...
- 113
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Clever projection of point onto triangle?
I know of at leas tone way to project a point onto a triangle.
Project onto the plane, check barycentric coordinates, if outisde triangle, project onto the 3 segments, check distance, retain closest ...
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Difference between perspective and parallel projection [closed]
We know that in orthographic Projection Projectors (projection vectors) are perpendicular to the projection plane.
And in Perspective Projection Object positions are transformed to the view plane ...
user17337
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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?
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Why need glClipControl-like extensions when implementing ReverseZ in opgl?
I read this article (https://developer.nvidia.com/content/depth-precision-visualized) about reverseZ and I'm confused about why is glClipControl necessary.Can't we juse modify ProjectionMatrix to make ...
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Why are vanishing point and centre of projection the same [closed]
We know that in perspective projection object positions are transformed to the view plane along lines that converge to the projection reference (center) point like this:
But many websites say that COP(...
user17390
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how to change the near clipping plane of a perspective projection matrix for OpenGL
I am trying to only change the near clipping plane of a given perspective projection matrix for OpenGL.
My problem is, that the near clipping plane is way too close, and the far clipping plane is very ...
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