The radius will return a maximum of 0.5 (because we are calculating the distance from the center of the viewport) so we need to double this range (by multiplying by two) to get a maximum of 1.0.
I believe this is incorrect. The length of a vector is defined as sqrt(x^2 + y^2). At maximum, x and y are both 0.5, resulting in sqrt(0.25 + 0.25) = sqrt(0.5). This means that the maximum is in fact 0.7071, which is sqrt(2)/2. This means that this multiplication actually returns a value in the range of [0, sqrt(2)]. Indeed, we can confirm this by adding the following the following to the top of hsb2rgb.
if (c.y > 1.0) {
return vec3(0);
}
This gives the following result.
Changing this to c.y > 1.4142 gives us the result not cropped by the black circle (ignoring some slight black corners due to rounding errors).
The "Colors" chapter states
and refers to the following source code.
I believe this is incorrect. The length of a vector is defined as
sqrt(x^2 + y^2). At maximum,xandyare both 0.5, resulting insqrt(0.25 + 0.25)=sqrt(0.5). This means that the maximum is in fact0.7071, which issqrt(2)/2. This means that this multiplication actually returns a value in the range of[0, sqrt(2)]. Indeed, we can confirm this by adding the following the following to the top ofhsb2rgb.This gives the following result.
Changing this to
c.y > 1.4142gives us the result not cropped by the black circle (ignoring some slight black corners due to rounding errors).