This reference is for Processing 3.0+. If you have a previous version, use the reference included with your software in the Help menu. If you see any errors or have suggestions, please let us know. If you prefer a more technical reference, visit the Processing Core Javadoc and Libraries Javadoc.

Name

blue()

Examples
example pic
color c = color(175, 100, 220);  // Define color 'c'
fill(c);  // Use color variable 'c' as fill color
rect(15, 20, 35, 60);  // Draw left rectangle

float blueValue = blue(c);  // Get blue in 'c'
println(blueValue);  // Prints "220.0"
fill(0, 0, blueValue);  // Use 'blueValue' in new fill
rect(50, 20, 35, 60);  // Draw right rectangle
Description Extracts the blue value from a color, scaled to match current colorMode(). The value is always returned as a float, so be careful not to assign it to an int value.

The blue() function is easy to use and understand, but it is slower than a technique called bit masking. When working in colorMode(RGB, 255), you can acheive the same results as blue() but with greater speed by using a bit mask to remove the other color components. For example, the following two lines of code are equivalent means of getting the blue value of the color value c:

float b1 = blue(c);   // Simpler, but slower to calculate
float b2 = c & 0xFF;  // Very fast to calculate
Syntax
blue(rgb)
Parameters
rgb int: any value of the color datatype
Returnsfloat
Relatedred()
green()
alpha()
hue()
saturation()
brightness()
>> (right shift)
Updated on July 30, 2016 04:31:58am EDT

Creative Commons License