Color class
Represents a color in the RGBA color space.
This representation is designed for simplicity of conversion to/from color
representations in various languages over compactness. For example, the
fields of this representation can be trivially provided to the constructor
of java.awt.Color in Java; it can also be trivially provided to UIColor's
+colorWithRed:green:blue:alpha method in iOS; and, with just a little
work, it can be easily formatted into a CSS rgba() string in JavaScript.
This reference page doesn't carry information about the absolute color space
that should be used to interpret the RGB value (e.g. sRGB, Adobe RGB,
DCI-P3, BT.2020, etc.). By default, applications should assume the sRGB
color space. When color equality needs to be decided, implementations,
unless documented otherwise, treat two colors as equal if all their red,
green, blue, and alpha values each differ by at most 1e-5. Example (Java):
import com.google.type.Color; // ... public static java.awt.Color
fromProto(Color protocolor) { float alpha = protocolor.hasAlpha() ?
protocolor.getAlpha().getValue() : 1.0; return new java.awt.Color(
protocolor.getRed(), protocolor.getGreen(), protocolor.getBlue(), alpha); }
public static Color toProto(java.awt.Color color) { float red = (float)
color.getRed(); float green = (float) color.getGreen(); float blue = (float)
color.getBlue(); float denominator = 255.0; Color.Builder resultBuilder =
Color .newBuilder() .setRed(red / denominator) .setGreen(green /
denominator) .setBlue(blue / denominator); int alpha = color.getAlpha(); if
(alpha != 255) { result.setAlpha( FloatValue .newBuilder()
.setValue(((float) alpha) / denominator) .build()); } return
resultBuilder.build(); } // ... Example (iOS / Obj-C): // ... static
UIColor* fromProto(Color* protocolor) { float red = [protocolor red];
float green = [protocolor green]; float blue = [protocolor blue];
FloatValue* alpha_wrapper = [protocolor alpha]; float alpha = 1.0; if
(alpha_wrapper != nil) { alpha = [alpha_wrapper value]; } return [UIColor
colorWithRed:red green:green blue:blue alpha:alpha]; } static Color*
toProto(UIColor* color) { CGFloat red, green, blue, alpha; if (![color
getRed:&red green:&green blue:&blue alpha:&alpha]) { return nil; } Color*
result = [[Color alloc] init]; [result setRed:red]; [result
setGreen:green]; [result setBlue:blue]; if (alpha <= 0.9999) { [result
setAlpha:floatWrapperWithValue(alpha)]; } [result autorelease]; return
result; } // ... Example (JavaScript): // ... var protoToCssColor =
function(rgb_color) { var redFrac = rgb_color.red || 0.0; var greenFrac =
rgb_color.green || 0.0; var blueFrac = rgb_color.blue || 0.0; var red =
Math.floor(redFrac * 255); var green = Math.floor(greenFrac * 255); var blue
= Math.floor(blueFrac * 255); if (!('alpha' in rgb_color)) { return
rgbToCssColor(red, green, blue); } var alphaFrac = rgb_color.alpha.value ||
0.0; var rgbParams = [red, green, blue].join(','); return ['rgba(',
rgbParams, ',', alphaFrac, ')'].join(''); }; var rgbToCssColor =
function(red, green, blue) { var rgbNumber = new Number((red << 16) |
(green << 8) | blue); var hexString = rgbNumber.toString(16); var
missingZeros = 6 - hexString.length; var resultBuilder = ['#']; for (var i
= 0; i < missingZeros; i++) { resultBuilder.push('0'); }
resultBuilder.push(hexString); return resultBuilder.join(''); }; // ...
Constructors
Properties
- alpha ↔ double?
-
The fraction of this color that should be applied to the pixel.
getter/setter pair
- blue ↔ double?
-
The amount of blue in the color as a value in the interval [0, 1].
getter/setter pair
- green ↔ double?
-
The amount of green in the color as a value in the interval [0, 1].
getter/setter pair
- hashCode → int
-
The hash code for this object.
no setterinherited
- red ↔ double?
-
The amount of red in the color as a value in the interval [0, 1].
getter/setter pair
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
Methods
-
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a nonexistent method or property is accessed.
inherited
-
toJson(
) → Map< String, dynamic> -
toString(
) → String -
A string representation of this object.
inherited
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited