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Name

red()

Examples
example pic
color c = color(255, 204, 0);  // Define color 'c'
fill(c);  // Use color variable 'c' as fill color
rect(15, 20, 35, 60);  // Draw left rectangle
	
float redValue = red(c);  // Get red in 'c'
println(redValue);  // Print "255.0"
fill(redValue, 0, 0);  // Use 'redValue' in new fill
rect(50, 20, 35, 60);  // Draw right rectangle
Description Extracts the red 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 red() function is easy to use and understand, but it is slower than a technique called bit shifting. When working in colorMode(RGB, 255), you can acheive the same results as red() but with greater speed by using the right shift operator (>>) with a bit mask. For example, the following two lines of code are equivalent means of getting the red value of the color value c:

float r1 = red(c);  // Simpler, but slower to calculate
float r2 = c >> 16 & 0xFF;  // Very fast to calculate
Syntax
red(rgb)
Parameters
rgb int: any value of the color datatype
Returnsfloat
Relatedgreen()
blue()
alpha()
hue()
saturation()
brightness()
>> (right shift)
Updated on August 17, 2014 07:01:13pm EDT

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