Compress a vec3 into a vec2

[Josh]

I didn't end up using this, but here's an interesting bit of code that can be used to compress an RGB color into two components. Does not work with blending:

vec2 toRGB565(in vec3 c)
{
ivec2 outcInt = ivec2(c.rb * 31.0);
int green = int(c.g*63.0);
ivec2 LOHI = ivec2(green & 7,green >> 3);
LOHI <<= ivec2(5);
return (vec2(outcInt | LOHI) / 255.0);
}

vec3 fromRGB565(in vec2 c)
{
vec3 outc;
ivec2 cInt = ivec2(c*255.0);
ivec2 cIntMod = cInt & 31;
outc.rb = vec2(cIntMod) / 31.0;
ivec2 gComps = cInt>>5;
outc.g = float(gComps.x | (gComps.y<<3)) / 63.0;
return outc;
}

[drarem]

I love this type of stuff.