Why does my cube in three.js have aliasing and look "Jaggy"? - graphics

I am using three.js and created a basic scene with a few meshses rendered with some basic lighting . My torus geometry was previously pointy with few polygons but I was able to smooth it out by adding more segments but now I would like to straighten the lines out in my cube. They seem jaggy. In the pic I am including my render on the left seems a lot jaggier then the example I am following on the right. I have even set width and height segments to very large values (200). Any Ideas why the aliasing/jagginess?My render on left, example on right

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How can I get overlapping translucent Godot sprites to keep the same opacity?

I have two simple translucent circle sprites that I'm using as fake shadows (shown below) under some characters (not shown below). When the characters get close enough, sometimes their shadow circles can overlap - which is fine - but thanks to the default blending it doesn't look right. I want the shadow circles that do overlap to be visually merged/mixed so they maintain the same opacity, but instead they add together where they overlap like this: I have to imagine there's some way to make this work with a shader, but I'm so bad at shaders that I can't seem to figure it out. Does anyone know how to solve this?

how to get a “thick” poly line from vtkPlaneCutter & vtkPolyData?

I am trying to cut a mesh with a plane and render the contour on top of an image (resliced along using the same plane), much like the image below:
The examples at https://gitlab.kitware.com/vtk/vtk/-/blob/v9.1.0/Filters/Core/Testing/Python/TestPolyDataPlaneCutter.py almost do the slicing part that I need
But when viewing the contour from the direction of the normal the contour / polyline is invisible (see screenshot below left side) as opposed to viewing it from the side (right side of the screenshot below)
So I assume I should try to "dilate" the resulting contour somehow? Any suggestions?

Edge value problems when generating bitmaps using SVG + CairoSVG

Me and my team have problems with generating bitmaps out of polygons. We've tried a few different solutions in order to generate polygons sufficiently fast and have found generating SVG paths and then using CairoSVG to be the best solution for us. We are using the even-odd rule to fill the polygons. I apologies if I'm describing everything in an incorrect way in terms of vocabulary, I'm new to SVG. The pathes are created as:
path_entry = f'<path fill="rgb{rgb_color}" fill-rule="evenodd" d="{svg_path}"/>'
With header
<svg
xmlnsXlink="http://www.w3.org/2000/svg"
preserveAspectRatio="xMinYMin meet"
style="color:green;"
>
We only allow the bitmap to have a set of color values. The value of a pixel should be that of the polygon which it's inside. A problem we've encountered is that the edges of the polygons "splits" pixels, i.e a pixel can be both on the edge/inside of polygon A and polygon B. See the image below where the edge between the black, green and grey area gets a mixed color.
We've currently solved this by finding each pixel that doesn't have an allowed color. We then use numpy roll to fill the value of these pixels with the value of its neighbours according to a solution found on this site.
for shift in (-1,1):
for axis in (0,1):
a_shifted=np.roll(bitmap_only_correct_colors,shift=shift,axis=axis)
idx=~a_shifted.mask * bitmap_only_correct_colors.mask
bitmap_only_correct_colors[idx]=a_shifted[idx]
The problem with this solution is thin diagonal polygons, 1-2 pixels thick. All pixels of these polygons get the mixed value and are therefor removed. This causes the thin polygons to be partly removed creating dotted lines instead of full lines, see the image below.
My question is: Can we solve this problem with the edges of the polygons not getting fixed values in another way? The best solution would be to add some kind of setting to the SVG-Document before generating the images.
Thank you!
Turn off anti-aliasing i.e. set shape-rendering="crispEdges" See the SVG specification for more details about this CSS property.

Calculate distortion in equirectangular projection on a sphere

Following Quote from this source:
http://www.cambridgeincolour.com/tutorials/image-projections.htm
Equirectangular image projections map the latitude and longitude
coordinates of a spherical globe directly onto horizontal and vertical
coordinates of a grid, where this grid is roughly twice as wide as it
is tall.
I have a 13312 px width and 6656 pixel height Panorama picture. It's a equirectangular projection of a room and have a 2:1 ratio.
I use following formular to calculate the xPosition:
var xPosition = ( panorama.width / 360 ) * azimuth
Azimuth = Phi = Heading = Angle to the left or right
How do I project this now on a 1366x768px browser screen?
I think my results are wrong, because it's not on the point where it should be.. it could be because the sphere has a distortion on the left and right:
Is there any formular to calculate the position with attention to the distortion and scale it to fit on the browser screen? I looked many (MANY) sources to find a solution for this, but they always just say that equirectangular are just lat and long.. they don't consider the distortion.
Last question: To find a special solution, I tryed to put a plane on the circle and expanded the line which shows the alpha angle. I though with Phytagoras I could find the position.. but this didn't worked either.. maybe I did something wrong? Is this the way even possible or am I doing it wrong?
edit
THIS is what I'm actually looking for: http://othree.github.io/360-panorama/three-2d/
The black grid in the background. What is the name of this? For what do I have to google or look for? When you start the 2D Panorama, if you want to get the coordinations of the top right corner of the window, what do you have to do?
The whole calculation problem was about to create a Google Streetview similiar view from a 2:1 equirectangular image. We already found a solution for this with a great help from Martin Matysiak (https://github.com/marmat | Google).
It's been a while so I can't give a direct answer to what the main solution is, but I can provide a URL to an AddOn Martin wrote for adding the custom Markers that we actually were trying to make.
You can follow https://github.com/marmat/google-maps-api-addons and look for yourself. In the end it helped a lot to solve the main problem and let us continue with our main Framework for Google Business Tours.
If you follow the link in the threejs demo you included, it would take you to the source code.
particularly look at:
https://github.com/mrdoob/three.js/blob/dev/examples/webgl_panorama_equirectangular.html
and
https://github.com/mrdoob/three.js/blob/dev/src/geometries/SphereBufferGeometry.js
not sure if there is distortion though. The distortion comes from the fact that the texture is mapped to the sphere, and the sphere is rendered in 3D (openGL).

Can you right-align an SVG rectangle?

I'm using Raphael to draw rectangles. Whoo-hoo!
Is there a way to right align contents of an SVG file?
Not just text, but shapes as well?
I can do the math and get the computed x value, but I'm looking for the lazy-simple solution.
Thank you.
There isn't. Unlike normal web pages where the window is resized and the content flows into it, when a Raphael paper is resized, there is no sort of flow, so aligning is irrelevant. Instead of setting align=right, you just set the right edge to be the same position you set the width of the paper to be. If you enlarge the paper, you can scale the contents with a single operation. Once you've set the position of the right edge, you've essentially set the align position. You don't need to re-set all edge values when the paper changes size, you just scale everything with one command. Hope that helps

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