Does Android ColorMatrix setSaturation() support values greater than one?
Looking at the Android docs, the ColorMatrix setSaturation() method says:
Set the matrix to affect the saturation of colors. A value of 0 maps the color to gray-scale. 1 is identity.
I'm trying to boost the saturation (in terms of HSL/HSV) to get more intense colors, so I passed in 1.6 and it seems to work. I've run into device-specific issues with Android layout shadowRadius values less than 1, so is there a danger of those types of issues with this parameter and exceeding the specified range?
The range for the saturation is indeed between 0 and 1. But lets take a look at the code for the setSaturation() method. (Android is open source):
public void setSaturation(float sat) {
reset();
float[] m = mArray;
final float invSat = 1 - sat; //<---------invSat will be negative if sat bigger than 1
final float R = 0.213f * invSat;
final float G = 0.715f * invSat;
final float B = 0.072f * invSat;
m[0] = R + sat; m[1] = G; m[2] = B;
m[5] = R; m[6] = G + sat; m[7] = B;
m[10] = R; m[11] = G; m[12] = B + sat;
}
The part of the code that we care about is pointed out. As you can see,The method will take your input and subtract it from 1. If you input a value greater than 1, this will result in a negative value for the invSat, and as you can see it may cause bigger problems as well.
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