Color typedef
Represents a color in the RGBA color space.
This representation is designed for simplicity of conversion to and 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 have information about the absolute
color space that should be used to interpret the RGB value—for example,
sRGB, Adobe RGB, DCI-P3, and BT.2020. 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(''); }; // ...
Implementation
typedef Color = $Color;