Author Topic: stars shader  (Read 150 times)

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mireazma

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stars shader
« on: March 27, 2015, 02:57:24 PM »
Hello there.

Can you guys give me a direction where to get assistance about making a specific shader?

I want to make a starry night sky from 2 separate textures: 1 for the sky background + 1 for the stars. The stars texture is 90% empty, as in RGBA(0, 0, 0, 0) and only have scattered white points or little blobs as stars.
I need an idea about how to make a shader for the stars texture to draw a cross for each star (horizontal/vertical spikes). The idea here is whenever camera is rotated the crosses stay unrotated.
One alternate way is to just have a pre-crossed star texture and draw it multiple times at different locations over the already rotated background. But with 1000 stars I'm afraid it's not going to be very economical. And I want to take advantage of the shader parallelism.

The shader would probably be something like the simple blur shader. I'm saying this because I guess it should "smudge" the points (original stars) upwards, downwards, left and right.

But I have no clue as to where to begin. Seeing those amazing Geeks3D shaders I thought what I want is doable relatively simply.