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#include <mbgl/style/expression/util.hpp>
#include <mbgl/style/expression/value.hpp>
namespace mbgl {
namespace style {
namespace expression {
std::string stringifyColor(double r, double g, double b, double a) {
return stringify(r) + ", " +
stringify(g) + ", " +
stringify(b) + ", " +
stringify(a);
}
Result<Color> rgba(double r, double g, double b, double a) {
if (
r < 0 || r > 255 ||
g < 0 || g > 255 ||
b < 0 || b > 255
) {
return EvaluationError {
"Invalid rgba value [" + stringifyColor(r, g, b, a) +
"]: 'r', 'g', and 'b' must be between 0 and 255."
};
}
if (a < 0 || a > 1) {
return EvaluationError {
"Invalid rgba value [" + stringifyColor(r, g, b, a) +
"]: 'a' must be between 0 and 1."
};
}
return Color(r / 255 * a, g / 255 * a, b / 255 * a, a);
}
} // namespace expression
} // namespace style
} // namespace mbgl
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