It would appear that the texture coordinates of a polyline are divided equally according to the number of segments, so given a 2 segment polyline, the S coordinate will be: 0, 0.5, 1.
This causes a problem when trying to implement a dashed line.
Here’s an illustration of the issue:
The dash density of the cyan line changes based on segment length.
I want the line to have texture coordinates that correspond to its segment’s length.
So for the same line, with 2 segments, if the first segment is three times the length of the second, the S coordinates should be: 0, 0.75, 1.
The built-in dashed line moves along with the camera, and was rejected by our designer.
Performance is also an issue, so making every segment a separate polyline is not feasible.
I have 2 potential solutions for this, but I’m in need of assistance with implementation.
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A custom shader that receives length dependent coordinates in its uniform.
For this method, I don’t know how to pass an array to the shader.
One suggestion I’ve seen is passing a 1D texture, but I’m a newbie in GLSL, and don’t know how to assign and retrieve the values. -
A custom polyline, where the texture coordinates are assigned based on segment length.
In this case, I just don’t know where the line is created.
If someone could direct me to the part of the code where this happens, I’m pretty sure I can make an alternative, or add some variable, that builds the mesh with normalized texture coordinates.
Any help is appreciated.
