Questions tagged [coordinates]
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12 questions
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Origins, Basis, and Axes
In the context of 3D graphics, and specifically of coordinate systems, we can think of there being a root coordinate system, and there being 0 or more nested child coordinate systems (CCS) within that ...
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Transforming UVs from rectangular to azimuthal spherical projection
I'm trying to figure out a general way to project a rectangular texture into a spherical one centered on the azimuth (UN flag style).
As a reference, I have been able to achieve this effect exactly ...
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Generate camera trajectory with cameras' lookat following shape
I am trying with no avail to create a camera path that follows a lemniscate shape as shown in the figure.
I do it in 3D but just set the vertical dimension (y) to a fixed number so really is 2D. the ...
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How are these two projection matrices related?
I have two 3D perspective projection matrices $A,B$ with standard projection parameters $k=\cot(\theta/2)$, where $\theta$ is the field of view, $n$ is the $z$-near value, $f$ is the $z$-far value, ...
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What to do with the homogeneous $w$ during vector operations
As I understand it: In graphics, 3D vectors are usually represented as homogeneous coordinates by storing an additional $w$ component known as the weight. The vector is divided by $w$ to obtain the ...
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How to achieve smooth max of two coordinates in a shader
I am trying to achieve a border effect to a square tile on a xz plane. I am using max of coordinates x and z to achieve that. Here is my ShaderLab code:
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Texture coordinates
Consider the square shown below on the left, which has been textured with the image shown on the right. What are the texture coordinates of the vertices a, b, c, and d?
Does anyone know how to answer ...
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Convert between screen and world coordinates in isometric 3D
I'm working on a a simple 3D scene in WebGL. The purpose is to:
Implement an isometric viewing angle in orthographic 3D
Translate between XY screen coordinates and XY world coordinates
Codepen: ...
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Computer Graphics Previous Year Question asked in UGC NET 2021
What is the transformation matrix M that transforms a square in the x-y plane defined by (1, 1)T (-1, 1)T (-1, -1)T (1, -1)T to a parallelogram whose corresponding vertices are (2, 1)T (0,1)T (-2, -1)...
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How to convert from world coordinates to camera coordinates
In the world coordinate system, there are objects with rotation values rx1,ry1,rz1 and position values px1,py1,pz1.
Similarly, ...
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Automate Image resize, scale, position for best quality (size)
I have a process where a web user selects a photo for a profile image. User is then presented with a canvas to zoom, rotate and move their image within a square viewport. Once satisfied, the user ...
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Understanding orthographic projection matrix clip coordinates
I'm confused about what orthographic projection matrix outputs. Based on what I know so far, orthographic projection matrix converts vertexes in eye coordinates into clip coordinates. But what exactly ...
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