Class: Google::Type::Color
- Inherits:
-
Object
- Object
- Google::Type::Color
- Extended by:
- Protobuf::MessageExts::ClassMethods
- Includes:
- Protobuf::MessageExts
- Defined in:
- proto_docs/google/type/color.rb
Overview
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, as well.
Note: this proto does not 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.
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('');
};
// ...
Instance Attribute Summary collapse
-
#alpha ⇒ ::Google::Protobuf::FloatValue
The fraction of this color that should be applied to the pixel.
-
#blue ⇒ ::Float
The amount of blue in the color as a value in the interval [0, 1].
-
#green ⇒ ::Float
The amount of green in the color as a value in the interval [0, 1].
-
#red ⇒ ::Float
The amount of red in the color as a value in the interval [0, 1].
Instance Attribute Details
#alpha ⇒ ::Google::Protobuf::FloatValue
Returns The fraction of this color that should be applied to the pixel. That is, the final pixel color is defined by the equation:
pixel color = alpha * (this color) + (1.0 - alpha) * (background color)
This means that a value of 1.0 corresponds to a solid color, whereas a value of 0.0 corresponds to a completely transparent color. This uses a wrapper message rather than a simple float scalar so that it is possible to distinguish between a default value and the value being unset. If omitted, this color object is to be rendered as a solid color (as if the alpha value had been explicitly given with a value of 1.0).
163 164 165 166 |
# File 'proto_docs/google/type/color.rb', line 163 class Color include ::Google::Protobuf::MessageExts extend ::Google::Protobuf::MessageExts::ClassMethods end |
#blue ⇒ ::Float
Returns The amount of blue in the color as a value in the interval [0, 1].
163 164 165 166 |
# File 'proto_docs/google/type/color.rb', line 163 class Color include ::Google::Protobuf::MessageExts extend ::Google::Protobuf::MessageExts::ClassMethods end |